<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2025 Workiva-->
<!--r:61c9e9fc-8b0b-460a-a8bb-a3d54bfa529a,g:0f49771a-90dc-431e-848a-2a093e1bafd7-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.newtekone.com/role/Cover" xlink:type="simple" xlink:href="newt-20241231.xsd#Cover"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/Cover" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable_90bf2925-b811-41d7-ae07-3375f234cd61" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_DocumentInformationTable_90bf2925-b811-41d7-ae07-3375f234cd61" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_98b4da63-eeeb-424c-9966-c2cf9a5f5f6e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_DocumentInformationTable_90bf2925-b811-41d7-ae07-3375f234cd61" xlink:to="loc_us-gaap_StatementClassOfStockAxis_98b4da63-eeeb-424c-9966-c2cf9a5f5f6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_98b4da63-eeeb-424c-9966-c2cf9a5f5f6e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_98b4da63-eeeb-424c-9966-c2cf9a5f5f6e" xlink:to="loc_us-gaap_ClassOfStockDomain_98b4da63-eeeb-424c-9966-c2cf9a5f5f6e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_09137ff0-fdcc-45a2-9a2d-3ebbf76c578a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_98b4da63-eeeb-424c-9966-c2cf9a5f5f6e" xlink:to="loc_us-gaap_ClassOfStockDomain_09137ff0-fdcc-45a2-9a2d-3ebbf76c578a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommonStockParValue002PerShareMember_9b818ad3-edad-4c03-89fb-9447c858c570" xlink:href="newt-20241231.xsd#newt_CommonStockParValue002PerShareMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_09137ff0-fdcc-45a2-9a2d-3ebbf76c578a" xlink:to="loc_newt_CommonStockParValue002PerShareMember_9b818ad3-edad-4c03-89fb-9447c858c570" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FivePointFiveZeroPercentNotesDue2026Member_6be5b256-d100-40c3-b7c7-4860044b844e" xlink:href="newt-20241231.xsd#newt_FivePointFiveZeroPercentNotesDue2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_09137ff0-fdcc-45a2-9a2d-3ebbf76c578a" xlink:to="loc_newt_FivePointFiveZeroPercentNotesDue2026Member_6be5b256-d100-40c3-b7c7-4860044b844e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2028NotesMember_df7b277e-df31-4418-a83a-846be3844d7e" xlink:href="newt-20241231.xsd#newt_A2028NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_09137ff0-fdcc-45a2-9a2d-3ebbf76c578a" xlink:to="loc_newt_A2028NotesMember_df7b277e-df31-4418-a83a-846be3844d7e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.50NotesMember_33c2bb0c-27d1-4f11-9db3-85005c2ba009" xlink:href="newt-20241231.xsd#newt_A20298.50NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_09137ff0-fdcc-45a2-9a2d-3ebbf76c578a" xlink:to="loc_newt_A20298.50NotesMember_33c2bb0c-27d1-4f11-9db3-85005c2ba009" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.625NotesMember_50cdd17b-9365-4fce-b241-e56226384630" xlink:href="newt-20241231.xsd#newt_A20298.625NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_09137ff0-fdcc-45a2-9a2d-3ebbf76c578a" xlink:to="loc_newt_A20298.625NotesMember_50cdd17b-9365-4fce-b241-e56226384630" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_425435d1-d38b-4838-8293-e3c352af62df" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_DocumentType_425435d1-d38b-4838-8293-e3c352af62df" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentAnnualReport_d9f11d00-1d69-40cf-af6a-004db7ebfbde" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentAnnualReport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_DocumentAnnualReport_d9f11d00-1d69-40cf-af6a-004db7ebfbde" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_67f04ac9-ecf0-49be-9f99-3144e6fe1ee2" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentPeriodEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_DocumentPeriodEndDate_67f04ac9-ecf0-49be-9f99-3144e6fe1ee2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CurrentFiscalYearEndDate_2e36dac2-bb8a-4505-9de0-a07e16f59236" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_CurrentFiscalYearEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_CurrentFiscalYearEndDate_2e36dac2-bb8a-4505-9de0-a07e16f59236" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentTransitionReport_c1bf1ac2-7269-4b16-8fba-d10b1a956e3d" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentTransitionReport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_DocumentTransitionReport_c1bf1ac2-7269-4b16-8fba-d10b1a956e3d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_1e72f647-3c1f-40d0-b559-1e95c9969a7b" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityFileNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityFileNumber_1e72f647-3c1f-40d0-b559-1e95c9969a7b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_0beaaa9f-20ae-4b48-8f0c-61e9eee5af19" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityRegistrantName_0beaaa9f-20ae-4b48-8f0c-61e9eee5af19" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_8791a637-faaa-4892-9f62-847bb3e6de01" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityIncorporationStateCountryCode_8791a637-faaa-4892-9f62-847bb3e6de01" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_eb7c3555-5ace-4223-8217-3aa8ae7fedfd" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityTaxIdentificationNumber_eb7c3555-5ace-4223-8217-3aa8ae7fedfd" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_5126b08c-c04c-4ac4-b162-f97136b94a0f" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityAddressAddressLine1_5126b08c-c04c-4ac4-b162-f97136b94a0f" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine2_e751cbf6-f085-4d50-af55-24c36efb21fa" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressAddressLine2"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityAddressAddressLine2_e751cbf6-f085-4d50-af55-24c36efb21fa" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_b822f40c-1d3e-479a-855a-50fcfb446354" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityAddressCityOrTown_b822f40c-1d3e-479a-855a-50fcfb446354" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_177262eb-526f-4ad8-88b9-d0ddcfe86496" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityAddressStateOrProvince_177262eb-526f-4ad8-88b9-d0ddcfe86496" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_e62f2916-b952-4a98-af52-5f063fe8fbc1" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityAddressPostalZipCode_e62f2916-b952-4a98-af52-5f063fe8fbc1" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_0402afcb-422a-4a93-a0e2-e3f29d434a97" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_CityAreaCode_0402afcb-422a-4a93-a0e2-e3f29d434a97" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_eac95d9c-39fb-4bb7-b8ef-ede962e7571a" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_LocalPhoneNumber_eac95d9c-39fb-4bb7-b8ef-ede962e7571a" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_5cbecc19-591c-47b9-8811-f397a3b3ed6e" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_Security12bTitle_5cbecc19-591c-47b9-8811-f397a3b3ed6e" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_014c981a-51d4-41fc-b718-d8c7efba6014" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_TradingSymbol_014c981a-51d4-41fc-b718-d8c7efba6014" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_e6911df0-3083-439f-9c7e-f36caf8920cb" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_SecurityExchangeName_e6911df0-3083-439f-9c7e-f36caf8920cb" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityWellKnownSeasonedIssuer_b12cd2e6-11e6-461f-b93a-b15682933efe" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityWellKnownSeasonedIssuer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityWellKnownSeasonedIssuer_b12cd2e6-11e6-461f-b93a-b15682933efe" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityVoluntaryFilers_36c523cd-6539-4292-9e07-d6a05c459645" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityVoluntaryFilers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityVoluntaryFilers_36c523cd-6539-4292-9e07-d6a05c459645" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCurrentReportingStatus_433982c5-1beb-4148-a34e-807f0f81d090" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityCurrentReportingStatus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityCurrentReportingStatus_433982c5-1beb-4148-a34e-807f0f81d090" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInteractiveDataCurrent_892beb7f-28ef-45d6-ac8f-4a9d1cb0e684" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityInteractiveDataCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityInteractiveDataCurrent_892beb7f-28ef-45d6-ac8f-4a9d1cb0e684" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFilerCategory_9eb88add-3a62-4f3f-a5a2-0715df7eeea4" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityFilerCategory"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityFilerCategory_9eb88add-3a62-4f3f-a5a2-0715df7eeea4" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitySmallBusiness_f97ee975-b2cb-4947-b11b-82ec88050d0f" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntitySmallBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntitySmallBusiness_f97ee975-b2cb-4947-b11b-82ec88050d0f" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_6cb9fdca-32eb-4738-8fa5-8ba80b6c1d50" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityEmergingGrowthCompany_6cb9fdca-32eb-4738-8fa5-8ba80b6c1d50" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_IcfrAuditorAttestationFlag_656ac3a4-c9ea-4197-8a99-8145f140f763" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_IcfrAuditorAttestationFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_IcfrAuditorAttestationFlag_656ac3a4-c9ea-4197-8a99-8145f140f763" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityShellCompany_865d26c6-6470-4e10-8aec-517d7cfa948b" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityShellCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityShellCompany_865d26c6-6470-4e10-8aec-517d7cfa948b" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFinStmtErrorCorrectionFlag_9a2fe8b7-6740-4fee-ab07-dacdab879220" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentFinStmtErrorCorrectionFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_DocumentFinStmtErrorCorrectionFlag_9a2fe8b7-6740-4fee-ab07-dacdab879220" xlink:type="arc" order="28"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityPublicFloat_01466b91-b462-46d8-9894-88ffd07e8f95" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityPublicFloat"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityPublicFloat_01466b91-b462-46d8-9894-88ffd07e8f95" xlink:type="arc" order="29"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_a86b7b18-e020-4b8c-bb08-e4bf466fdbf2" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityCommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityCommonStockSharesOutstanding_a86b7b18-e020-4b8c-bb08-e4bf466fdbf2" xlink:type="arc" order="30"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_8949552f-4766-4b09-97d1-562c5cdbec7c" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityCentralIndexKey"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_EntityCentralIndexKey_8949552f-4766-4b09-97d1-562c5cdbec7c" xlink:type="arc" order="31"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_9394b93b-4df7-4965-85ba-10c780395e9c" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_AmendmentFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_AmendmentFlag_9394b93b-4df7-4965-85ba-10c780395e9c" xlink:type="arc" order="32"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalYearFocus_5156bcb2-7eb0-4c6b-9968-2257f37d7ea0" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentFiscalYearFocus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_DocumentFiscalYearFocus_5156bcb2-7eb0-4c6b-9968-2257f37d7ea0" xlink:type="arc" order="33"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalPeriodFocus_5703ed8a-c3b0-4787-8ba4-7ede20f66577" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentFiscalPeriodFocus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_b1f6f13b-5607-4bff-98fc-976edc0d843b" xlink:to="loc_dei_DocumentFiscalPeriodFocus_5703ed8a-c3b0-4787-8ba4-7ede20f66577" xlink:type="arc" order="34"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/CONSOLIDATEDSTATEMENTSOFFINANCIALCONDITION" xlink:type="simple" xlink:href="newt-20241231.xsd#CONSOLIDATEDSTATEMENTSOFFINANCIALCONDITION"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/CONSOLIDATEDSTATEMENTSOFFINANCIALCONDITION" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_2d3c6522-9bf9-43ca-b8a8-364d2dab5d6b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_66dc11af-a2d3-4f8e-b76f-4ceb67f56081" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_2d3c6522-9bf9-43ca-b8a8-364d2dab5d6b" xlink:to="loc_us-gaap_StatementTable_66dc11af-a2d3-4f8e-b76f-4ceb67f56081" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_4c07308c-a7e0-4a27-a873-a75753ae2579" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_66dc11af-a2d3-4f8e-b76f-4ceb67f56081" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_4c07308c-a7e0-4a27-a873-a75753ae2579" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_4c07308c-a7e0-4a27-a873-a75753ae2579_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_4c07308c-a7e0-4a27-a873-a75753ae2579" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_4c07308c-a7e0-4a27-a873-a75753ae2579_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_143f6944-27bc-4fab-b6ec-0915073575b0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_4c07308c-a7e0-4a27-a873-a75753ae2579" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_143f6944-27bc-4fab-b6ec-0915073575b0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember_3ec8f776-9a13-4e01-9c11-990ab1f86751" xlink:href="newt-20241231.xsd#newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_143f6944-27bc-4fab-b6ec-0915073575b0" xlink:to="loc_newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember_3ec8f776-9a13-4e01-9c11-990ab1f86751" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_2d3c6522-9bf9-43ca-b8a8-364d2dab5d6b" xlink:to="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Cash_63efec10-a0c1-423e-9eb5-c04df53d8315" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Cash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_Cash_63efec10-a0c1-423e-9eb5-c04df53d8315" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCash_53528175-a05e-46cd-bb14-021c13b7a269" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_RestrictedCash_53528175-a05e-46cd-bb14-021c13b7a269" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DueFromBanks_13d47f78-1917-4291-8611-8d2d141321d5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DueFromBanks"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_DueFromBanks_13d47f78-1917-4291-8611-8d2d141321d5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_ad569c6e-5765-4b51-b37e-5d6fdfcc1e2e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_ad569c6e-5765-4b51-b37e-5d6fdfcc1e2e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketableSecurities_92d8c28d-eb6d-4c8b-955c-67f042a81645" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketableSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_MarketableSecurities_92d8c28d-eb6d-4c8b-955c-67f042a81645" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableHeldForSaleAmount_b348987d-4f2a-41df-bd52-b5fb13744270" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LoansReceivableHeldForSaleAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_LoansReceivableHeldForSaleAmount_b348987d-4f2a-41df-bd52-b5fb13744270" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableHeldForSaleLowerOfCostOrMarket_2be2db45-5d66-41e8-860b-8bafc0797aa7" xlink:href="newt-20241231.xsd#newt_FinancingReceivableHeldForSaleLowerOfCostOrMarket"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_newt_FinancingReceivableHeldForSaleLowerOfCostOrMarket_2be2db45-5d66-41e8-860b-8bafc0797aa7" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure_cee2d505-48ed-41aa-a5e2-f1c40f1a9f69" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure_cee2d505-48ed-41aa-a5e2-f1c40f1a9f69" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_f009ea4d-4bad-4768-90c2-b9164f153b94" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_f009ea4d-4bad-4768-90c2-b9164f153b94" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_36ef944f-0eff-437f-8d39-519e146ccb45" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_36ef944f-0eff-437f-8d39-519e146ccb45" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_fbacc2ac-55aa-48b3-a877-fe4c4d0ac25a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_fbacc2ac-55aa-48b3-a877-fe4c4d0ac25a" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankStockAndFederalReserveBankStock_bd279f82-d0e5-4547-8319-9ee810777c12" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FederalHomeLoanBankStockAndFederalReserveBankStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_FederalHomeLoanBankStockAndFederalReserveBankStock_bd279f82-d0e5-4547-8319-9ee810777c12" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReceivablesFromBrokersDealersAndClearingOrganizations_8cb1e862-03fb-4690-baa3-36d05b230f03" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReceivablesFromBrokersDealersAndClearingOrganizations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_ReceivablesFromBrokersDealersAndClearingOrganizations_8cb1e862-03fb-4690-baa3-36d05b230f03" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_441f439d-b487-4f8e-8561-7e608c48a5c8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_441f439d-b487-4f8e-8561-7e608c48a5c8" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill_a2b05c77-e1fc-4eef-9ef2-5647da0c3798" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IntangibleAssetsNetIncludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill_a2b05c77-e1fc-4eef-9ef2-5647da0c3798" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_fec6cacb-9153-4f85-adf3-48d822a08970" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_fec6cacb-9153-4f85-adf3-48d822a08970" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxAssetsNet_75692ddd-2651-4b72-abbb-8c050daee292" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredIncomeTaxAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_DeferredIncomeTaxAssetsNet_75692ddd-2651-4b72-abbb-8c050daee292" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetAtFairValueAmount_bef0988c-4641-498b-a0e0-a0b778a2d025" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetAtFairValueAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_ServicingAssetAtFairValueAmount_bef0988c-4641-498b-a0e0-a0b778a2d025" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetAtAmortizedValue_2d41b961-95b6-4a87-8988-9ba28f6b95a1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetAtAmortizedValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_ServicingAssetAtAmortizedValue_2d41b961-95b6-4a87-8988-9ba28f6b95a1" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssets_9533656d-9d9f-4828-9f80-6be7e727906b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_OtherAssets_9533656d-9d9f-4828-9f80-6be7e727906b" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation_707aece6-f18e-4f66-a743-e8e9487256da" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation_707aece6-f18e-4f66-a743-e8e9487256da" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_08e6e68d-859d-42cd-aff4-fed000b1bcdd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b4790085-eed6-4ba0-9922-c3353ca2602f" xlink:to="loc_us-gaap_Assets_08e6e68d-859d-42cd-aff4-fed000b1bcdd" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_cfa7178a-e1bb-4d2a-ad9a-a3fde1212d93" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_2d3c6522-9bf9-43ca-b8a8-364d2dab5d6b" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_cfa7178a-e1bb-4d2a-ad9a-a3fde1212d93" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_cfa7178a-e1bb-4d2a-ad9a-a3fde1212d93" xlink:to="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsInterestBearingAndNoninterestBearingAlternativeAbstract_a53b4e11-30e3-4cbd-a0f1-a14bc1f82d3d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepositsInterestBearingAndNoninterestBearingAlternativeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:to="loc_us-gaap_DepositsInterestBearingAndNoninterestBearingAlternativeAbstract_a53b4e11-30e3-4cbd-a0f1-a14bc1f82d3d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestBearingDepositLiabilities_d6c9316d-67e6-4a2f-acff-4d5baf53781a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestBearingDepositLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DepositsInterestBearingAndNoninterestBearingAlternativeAbstract_a53b4e11-30e3-4cbd-a0f1-a14bc1f82d3d" xlink:to="loc_us-gaap_NoninterestBearingDepositLiabilities_d6c9316d-67e6-4a2f-acff-4d5baf53781a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestBearingDepositLiabilities_b5c78a6b-dff2-4994-b705-1ecadaa783d1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestBearingDepositLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DepositsInterestBearingAndNoninterestBearingAlternativeAbstract_a53b4e11-30e3-4cbd-a0f1-a14bc1f82d3d" xlink:to="loc_us-gaap_InterestBearingDepositLiabilities_b5c78a6b-dff2-4994-b705-1ecadaa783d1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Deposits_0e8a8568-2bca-43d3-96f6-c0bcee3280cd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Deposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DepositsInterestBearingAndNoninterestBearingAlternativeAbstract_a53b4e11-30e3-4cbd-a0f1-a14bc1f82d3d" xlink:to="loc_us-gaap_Deposits_0e8a8568-2bca-43d3-96f6-c0bcee3280cd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_b3e177ec-95e2-49f3-a429-25816e54d822" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:to="loc_us-gaap_LongTermDebt_b3e177ec-95e2-49f3-a429-25816e54d822" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsPayableCurrentAndNoncurrent_8b396996-b674-41cd-8d72-3e75e07667c0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DividendsPayableCurrentAndNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:to="loc_us-gaap_DividendsPayableCurrentAndNoncurrent_8b396996-b674-41cd-8d72-3e75e07667c0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_f6afe9cc-09f3-4b5a-9331-583698c1328f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:to="loc_us-gaap_OperatingLeaseLiability_f6afe9cc-09f3-4b5a-9331-583698c1328f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilitiesNet_a4286db2-e142-4cea-95b2-58e2f9a13fe3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredIncomeTaxLiabilitiesNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:to="loc_us-gaap_DeferredIncomeTaxLiabilitiesNet_a4286db2-e142-4cea-95b2-58e2f9a13fe3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DueToParticipants_f92adca6-2611-45ec-b8f4-1ba8a6f1908b" xlink:href="newt-20241231.xsd#newt_DueToParticipants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:to="loc_newt_DueToParticipants_f92adca6-2611-45ec-b8f4-1ba8a6f1908b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableAndOtherAccruedLiabilities_7bfe12d6-9eeb-4aab-b936-245881bdfcc7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsPayableAndOtherAccruedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:to="loc_us-gaap_AccountsPayableAndOtherAccruedLiabilities_7bfe12d6-9eeb-4aab-b936-245881bdfcc7" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_c4ae65ec-6fe4-4277-b181-0420dd137387" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_c4ae65ec-6fe4-4277-b181-0420dd137387" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_e3560362-a264-4bbc-839a-5b5807e4bd08" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_1088ea2c-2fab-4217-839e-d69e9cda113a" xlink:to="loc_us-gaap_Liabilities_e3560362-a264-4bbc-839a-5b5807e4bd08" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingencies_ea672d01-da34-489f-8765-d38acfd81e5e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommitmentsAndContingencies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_cfa7178a-e1bb-4d2a-ad9a-a3fde1212d93" xlink:to="loc_us-gaap_CommitmentsAndContingencies_ea672d01-da34-489f-8765-d38acfd81e5e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityAbstract_12c37edb-b0dd-4de4-a80b-64e1640e5173" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_cfa7178a-e1bb-4d2a-ad9a-a3fde1212d93" xlink:to="loc_us-gaap_StockholdersEquityAbstract_12c37edb-b0dd-4de4-a80b-64e1640e5173" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockValue_497697c7-8c75-4156-8fb1-794b503b653d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_12c37edb-b0dd-4de4-a80b-64e1640e5173" xlink:to="loc_us-gaap_PreferredStockValue_497697c7-8c75-4156-8fb1-794b503b653d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_598cd75b-6ee2-4fd4-8f5f-8cf1290a2f3f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_12c37edb-b0dd-4de4-a80b-64e1640e5173" xlink:to="loc_us-gaap_CommonStockValue_598cd75b-6ee2-4fd4-8f5f-8cf1290a2f3f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_f6a6e4b4-a33b-4d73-9d86-9597f8818a86" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AdditionalPaidInCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_12c37edb-b0dd-4de4-a80b-64e1640e5173" xlink:to="loc_us-gaap_AdditionalPaidInCapital_f6a6e4b4-a33b-4d73-9d86-9597f8818a86" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_bae85064-b7bb-4657-81a6-6f606c3e27ed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_12c37edb-b0dd-4de4-a80b-64e1640e5173" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_bae85064-b7bb-4657-81a6-6f606c3e27ed" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_19ce5e83-50b6-44fa-a71d-cfb64106406f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_12c37edb-b0dd-4de4-a80b-64e1640e5173" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_19ce5e83-50b6-44fa-a71d-cfb64106406f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_b499a856-3225-4e14-9015-a9de78f458df" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_12c37edb-b0dd-4de4-a80b-64e1640e5173" xlink:to="loc_us-gaap_StockholdersEquity_b499a856-3225-4e14-9015-a9de78f458df" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_fab1a99c-c3e7-4959-88dd-a94b46656082" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_cfa7178a-e1bb-4d2a-ad9a-a3fde1212d93" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_fab1a99c-c3e7-4959-88dd-a94b46656082" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/CONSOLIDATEDSTATEMENTSOFINCOME" xlink:type="simple" xlink:href="newt-20241231.xsd#CONSOLIDATEDSTATEMENTSOFINCOME"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/CONSOLIDATEDSTATEMENTSOFINCOME" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_77d3f050-0824-445a-82e2-38005fc4551e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_StatementTable_77d3f050-0824-445a-82e2-38005fc4551e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_1cda4978-bde9-4b89-9398-c1d0cc1a6b12" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_77d3f050-0824-445a-82e2-38005fc4551e" xlink:to="loc_us-gaap_DebtInstrumentAxis_1cda4978-bde9-4b89-9398-c1d0cc1a6b12" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_1cda4978-bde9-4b89-9398-c1d0cc1a6b12_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_1cda4978-bde9-4b89-9398-c1d0cc1a6b12" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_1cda4978-bde9-4b89-9398-c1d0cc1a6b12_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_9b02e80c-d09c-4dc8-bd79-46927b0b924e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_1cda4978-bde9-4b89-9398-c1d0cc1a6b12" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_9b02e80c-d09c-4dc8-bd79-46927b0b924e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NotesAndSecuritizationTrustsMember_9ef12287-c75e-456e-9e60-a8df0770ecac" xlink:href="newt-20241231.xsd#newt_NotesAndSecuritizationTrustsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_9b02e80c-d09c-4dc8-bd79-46927b0b924e" xlink:to="loc_newt_NotesAndSecuritizationTrustsMember_9ef12287-c75e-456e-9e60-a8df0770ecac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BankAndFederalHomeLoanBankBorrowingsMember_13ea92d7-d372-4d84-aab9-fe8dee29ad25" xlink:href="newt-20241231.xsd#newt_BankAndFederalHomeLoanBankBorrowingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_9b02e80c-d09c-4dc8-bd79-46927b0b924e" xlink:to="loc_newt_BankAndFederalHomeLoanBankBorrowingsMember_13ea92d7-d372-4d84-aab9-fe8dee29ad25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_a44d71a2-ba9d-47eb-b3c3-b18ae2b6ec3f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_77d3f050-0824-445a-82e2-38005fc4551e" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_a44d71a2-ba9d-47eb-b3c3-b18ae2b6ec3f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_a44d71a2-ba9d-47eb-b3c3-b18ae2b6ec3f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_a44d71a2-ba9d-47eb-b3c3-b18ae2b6ec3f" xlink:to="loc_us-gaap_RelatedPartyDomain_a44d71a2-ba9d-47eb-b3c3-b18ae2b6ec3f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_4d055616-ed10-4975-a518-fcd2f74a1adb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_a44d71a2-ba9d-47eb-b3c3-b18ae2b6ec3f" xlink:to="loc_us-gaap_RelatedPartyDomain_4d055616-ed10-4975-a518-fcd2f74a1adb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_5fb1055d-fe0c-414c-9597-0f6f47221b35" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_4d055616-ed10-4975-a518-fcd2f74a1adb" xlink:to="loc_us-gaap_RelatedPartyMember_5fb1055d-fe0c-414c-9597-0f6f47221b35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesAbstract_33270eec-c23b-4811-b65b-7b73d4e3e24c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RevenuesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_RevenuesAbstract_33270eec-c23b-4811-b65b-7b73d4e3e24c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeDebtSecuritiesAvailableForSaleOperating_aa6fb7e2-6433-403d-8006-52058d1b67b8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeDebtSecuritiesAvailableForSaleOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_33270eec-c23b-4811-b65b-7b73d4e3e24c" xlink:to="loc_us-gaap_InterestIncomeDebtSecuritiesAvailableForSaleOperating_aa6fb7e2-6433-403d-8006-52058d1b67b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndFeeIncomeLoansAndLeases_54eddd84-fedf-4279-b17a-90df2fb30a06" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestAndFeeIncomeLoansAndLeases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_33270eec-c23b-4811-b65b-7b73d4e3e24c" xlink:to="loc_us-gaap_InterestAndFeeIncomeLoansAndLeases_54eddd84-fedf-4279-b17a-90df2fb30a06" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeInterestEarningAsset_c26270fb-4da4-4318-81bd-70ca0cd11fca" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeInterestEarningAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_33270eec-c23b-4811-b65b-7b73d4e3e24c" xlink:to="loc_us-gaap_InterestIncomeInterestEarningAsset_c26270fb-4da4-4318-81bd-70ca0cd11fca" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOther_9c1347d2-9081-4d74-940f-55070dec02b0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_33270eec-c23b-4811-b65b-7b73d4e3e24c" xlink:to="loc_us-gaap_InterestIncomeOther_9c1347d2-9081-4d74-940f-55070dec02b0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOperating_be42a664-80d5-4541-8bbd-bb3689f498ff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_33270eec-c23b-4811-b65b-7b73d4e3e24c" xlink:to="loc_us-gaap_InterestIncomeOperating_be42a664-80d5-4541-8bbd-bb3689f498ff" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpensesAbstract_24f60ec7-5dc8-4048-b345-ac8370754763" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_OperatingExpensesAbstract_24f60ec7-5dc8-4048-b345-ac8370754763" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDeposits_90865f41-62db-4ec1-aa23-bc4386c5ca4e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDeposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_24f60ec7-5dc8-4048-b345-ac8370754763" xlink:to="loc_us-gaap_InterestExpenseDeposits_90865f41-62db-4ec1-aa23-bc4386c5ca4e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_851910e4-38b2-4364-951e-cee08e07a107" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_24f60ec7-5dc8-4048-b345-ac8370754763" xlink:to="loc_us-gaap_InterestExpenseDebt_851910e4-38b2-4364-951e-cee08e07a107" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InterestExpenseNotesPayable_9811e9b7-da61-45cf-a8f9-875e3ca31ecc" xlink:href="newt-20241231.xsd#newt_InterestExpenseNotesPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_24f60ec7-5dc8-4048-b345-ac8370754763" xlink:to="loc_newt_InterestExpenseNotesPayable_9811e9b7-da61-45cf-a8f9-875e3ca31ecc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseOperating_e1fe41a4-5960-4b6d-9334-c4061824b01a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_24f60ec7-5dc8-4048-b345-ac8370754763" xlink:to="loc_us-gaap_InterestExpenseOperating_e1fe41a4-5960-4b6d-9334-c4061824b01a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNet_ed3ff463-82c2-49b6-9622-97654e2b4587" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_InterestIncomeExpenseNet_ed3ff463-82c2-49b6-9622-97654e2b4587" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForLoanLeaseAndOtherLosses_7760bcdf-3dbe-4a4b-ae4d-b2b43f6a4af2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProvisionForLoanLeaseAndOtherLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_ProvisionForLoanLeaseAndOtherLosses_7760bcdf-3dbe-4a4b-ae4d-b2b43f6a4af2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_5aac37b6-eabc-4860-a265-39e7479e8059" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_5aac37b6-eabc-4860-a265-39e7479e8059" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestIncomeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeDividend_d6282969-47af-4d8a-836d-8aa7d40a5825" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIncomeDividend"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:to="loc_us-gaap_InvestmentIncomeDividend_d6282969-47af-4d8a-836d-8aa7d40a5825" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NetIncomeLossOnLoanServicingAsset_9fcb2fa2-253d-4647-af25-a312e2cf6f74" xlink:href="newt-20241231.xsd#newt_NetIncomeLossOnLoanServicingAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:to="loc_newt_NetIncomeLossOnLoanServicingAsset_9fcb2fa2-253d-4647-af25-a312e2cf6f74" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets_407c3f57-83d9-4031-8fd1-d1ddda6e742b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:to="loc_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets_407c3f57-83d9-4031-8fd1-d1ddda6e742b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSalesOfLoansNet_aaa1108d-08ee-4967-ac04-beac32d22b46" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainLossOnSalesOfLoansNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:to="loc_us-gaap_GainLossOnSalesOfLoansNet_aaa1108d-08ee-4967-ac04-beac32d22b46" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_UnrealizedGainLossOnSalesOfLoansNetFairValueOption_83cf5fd6-c01f-449a-8f0b-06e89044caf2" xlink:href="newt-20241231.xsd#newt_UnrealizedGainLossOnSalesOfLoansNetFairValueOption"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:to="loc_newt_UnrealizedGainLossOnSalesOfLoansNetFairValueOption_83cf5fd6-c01f-449a-8f0b-06e89044caf2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_WebHostingAndITSupportIncome_61f8db64-2456-43be-af35-394bcef1be91" xlink:href="newt-20241231.xsd#newt_WebHostingAndITSupportIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:to="loc_newt_WebHostingAndITSupportIncome_61f8db64-2456-43be-af35-394bcef1be91" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ElectronicPaymentProcessingIncome_af120acb-41d7-497d-8f32-034b63258648" xlink:href="newt-20241231.xsd#newt_ElectronicPaymentProcessingIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:to="loc_newt_ElectronicPaymentProcessingIncome_af120acb-41d7-497d-8f32-034b63258648" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncomeOther_ab7e5886-e59d-417f-9188-8ac74d7149f0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestIncomeOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:to="loc_us-gaap_NoninterestIncomeOther_ab7e5886-e59d-417f-9188-8ac74d7149f0" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncome_005a4425-ba11-4dfc-82bd-6f169ca3f13c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_98a77f3c-8f85-4ea2-a45c-419f8a876f9d" xlink:to="loc_us-gaap_NoninterestIncome_005a4425-ba11-4dfc-82bd-6f169ca3f13c" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestExpenseAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense_746ec991-4205-4a10-88a3-c3ef2bcb3b52" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:to="loc_us-gaap_LaborAndRelatedExpense_746ec991-4205-4a10-88a3-c3ef2bcb3b52" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InformationTechnologyAndDataProcessing_40ea4de2-4013-41f3-98a8-885f07f02a04" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InformationTechnologyAndDataProcessing"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:to="loc_us-gaap_InformationTechnologyAndDataProcessing_40ea4de2-4013-41f3-98a8-885f07f02a04" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ElectronicPaymentProcessingExpense_dd51105a-bfd2-4a97-8f42-8e9fcf7fefdf" xlink:href="newt-20241231.xsd#newt_ElectronicPaymentProcessingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:to="loc_newt_ElectronicPaymentProcessingExpense_dd51105a-bfd2-4a97-8f42-8e9fcf7fefdf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfessionalFees_4ab2c8d1-db7b-4707-8d07-5ca46088bb17" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProfessionalFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:to="loc_us-gaap_ProfessionalFees_4ab2c8d1-db7b-4707-8d07-5ca46088bb17" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LoanProcessingFeeOther_b1a90667-2a85-48f9-9024-56cd9fe35629" xlink:href="newt-20241231.xsd#newt_LoanProcessingFeeOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:to="loc_newt_LoanProcessingFeeOther_b1a90667-2a85-48f9-9024-56cd9fe35629" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_111df5d1-e75f-4833-98f5-9df5f2230c86" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_111df5d1-e75f-4833-98f5-9df5f2230c86" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_c2dc9620-b3c4-41a7-9c55-e3828cafdfc0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_c2dc9620-b3c4-41a7-9c55-e3828cafdfc0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherGeneralAndAdministrativeExpense_a9e04089-9e85-4628-964a-78ff3c9fa3a2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherGeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:to="loc_us-gaap_OtherGeneralAndAdministrativeExpense_a9e04089-9e85-4628-964a-78ff3c9fa3a2" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestExpense_54989724-3576-4bf7-b342-57ea7f2e12b0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_9f3e90db-1365-41d3-a031-709e84446c57" xlink:to="loc_us-gaap_NoninterestExpense_54989724-3576-4bf7-b342-57ea7f2e12b0" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossAttributableToParent_1f725aae-866d-4123-800d-f0269b163a9f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_IncomeLossAttributableToParent_1f725aae-866d-4123-800d-f0269b163a9f" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_9656339b-59da-42ef-be86-f8333d325ad1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_9656339b-59da-42ef-be86-f8333d325ad1" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_47ea433e-f82b-46a6-b0f9-be02d013dd77" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_NetIncomeLoss_47ea433e-f82b-46a6-b0f9-be02d013dd77" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsPreferredStock_daf6dcfb-7542-4523-aa87-646915579b64" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DividendsPreferredStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_DividendsPreferredStock_daf6dcfb-7542-4523-aa87-646915579b64" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_3007a4d1-cabe-42fb-b046-290a4a30315d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_3007a4d1-cabe-42fb-b046-290a4a30315d" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareAbstract_031b5946-4330-44c8-a506-d430295af51b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EarningsPerShareAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_515f5361-ebd5-462e-8b90-ec3836971a59" xlink:to="loc_us-gaap_EarningsPerShareAbstract_031b5946-4330-44c8-a506-d430295af51b" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_924652b4-7b3a-4321-9d2c-ba0b0886bff9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_031b5946-4330-44c8-a506-d430295af51b" xlink:to="loc_us-gaap_EarningsPerShareBasic_924652b4-7b3a-4321-9d2c-ba0b0886bff9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_d2e702a5-ba5c-4376-8d3a-2e10b0241b94" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_031b5946-4330-44c8-a506-d430295af51b" xlink:to="loc_us-gaap_EarningsPerShareDiluted_d2e702a5-ba5c-4376-8d3a-2e10b0241b94" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/CONSOLIDATEDSTATEMENTSOFCHANGESINSHAREHOLDERSEQUITY" xlink:type="simple" xlink:href="newt-20241231.xsd#CONSOLIDATEDSTATEMENTSOFCHANGESINSHAREHOLDERSEQUITY"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/CONSOLIDATEDSTATEMENTSOFCHANGESINSHAREHOLDERSEQUITY" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_c9bc5487-1010-4cc3-b7e1-620d56f8c03b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_9bd49960-1236-4025-a6d4-8263d988d974" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_c9bc5487-1010-4cc3-b7e1-620d56f8c03b" xlink:to="loc_us-gaap_StatementTable_9bd49960-1236-4025-a6d4-8263d988d974" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_5c9e89a4-22f2-44eb-84f4-4f6ec49a6f5e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_9bd49960-1236-4025-a6d4-8263d988d974" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_5c9e89a4-22f2-44eb-84f4-4f6ec49a6f5e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_5c9e89a4-22f2-44eb-84f4-4f6ec49a6f5e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_5c9e89a4-22f2-44eb-84f4-4f6ec49a6f5e" xlink:to="loc_us-gaap_EquityComponentDomain_5c9e89a4-22f2-44eb-84f4-4f6ec49a6f5e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_6527b673-4da4-45db-bd1a-3e2d4708fc1c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_5c9e89a4-22f2-44eb-84f4-4f6ec49a6f5e" xlink:to="loc_us-gaap_EquityComponentDomain_6527b673-4da4-45db-bd1a-3e2d4708fc1c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_a18a61c6-e836-4ea8-aa83-2aad19500b59" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6527b673-4da4-45db-bd1a-3e2d4708fc1c" xlink:to="loc_us-gaap_CommonStockMember_a18a61c6-e836-4ea8-aa83-2aad19500b59" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockMember_ffd98b57-7527-4bcd-b62a-c52ae479b28b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6527b673-4da4-45db-bd1a-3e2d4708fc1c" xlink:to="loc_us-gaap_PreferredStockMember_ffd98b57-7527-4bcd-b62a-c52ae479b28b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_bdaa89d4-1707-49fa-b6f0-470e731ff223" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6527b673-4da4-45db-bd1a-3e2d4708fc1c" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_bdaa89d4-1707-49fa-b6f0-470e731ff223" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociIncludingPortionAttributableToNoncontrollingInterestMember_ab2f976e-5e6b-4506-91ff-0ae144732a70" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AociIncludingPortionAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6527b673-4da4-45db-bd1a-3e2d4708fc1c" xlink:to="loc_us-gaap_AociIncludingPortionAttributableToNoncontrollingInterestMember_ab2f976e-5e6b-4506-91ff-0ae144732a70" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDistributionsInExcessOfNetIncomeMember_358e01da-9510-4f61-8b03-6ed19b56d9ee" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedDistributionsInExcessOfNetIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6527b673-4da4-45db-bd1a-3e2d4708fc1c" xlink:to="loc_us-gaap_AccumulatedDistributionsInExcessOfNetIncomeMember_358e01da-9510-4f61-8b03-6ed19b56d9ee" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_7eacd318-138f-42d6-a19c-344f9a32cce9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6527b673-4da4-45db-bd1a-3e2d4708fc1c" xlink:to="loc_us-gaap_RetainedEarningsMember_7eacd318-138f-42d6-a19c-344f9a32cce9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_dc6019bf-086d-4e55-800f-fad7fc23f387" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_9bd49960-1236-4025-a6d4-8263d988d974" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_dc6019bf-086d-4e55-800f-fad7fc23f387" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_dc6019bf-086d-4e55-800f-fad7fc23f387_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_dc6019bf-086d-4e55-800f-fad7fc23f387" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_dc6019bf-086d-4e55-800f-fad7fc23f387_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_1343f1aa-1378-4c5f-b86c-7c84aaf1539d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_dc6019bf-086d-4e55-800f-fad7fc23f387" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_1343f1aa-1378-4c5f-b86c-7c84aaf1539d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_7320f514-ec35-4708-ad49-23ee13c34e20" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentAffiliatedIssuerControlledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_1343f1aa-1378-4c5f-b86c-7c84aaf1539d" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_7320f514-ec35-4708-ad49-23ee13c34e20" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementAxis_abcc0706-5dbc-4271-98aa-96854998d5d9" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RestatementAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_9bd49960-1236-4025-a6d4-8263d988d974" xlink:to="loc_srt_RestatementAxis_abcc0706-5dbc-4271-98aa-96854998d5d9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementDomain_abcc0706-5dbc-4271-98aa-96854998d5d9_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RestatementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RestatementAxis_abcc0706-5dbc-4271-98aa-96854998d5d9" xlink:to="loc_srt_RestatementDomain_abcc0706-5dbc-4271-98aa-96854998d5d9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementDomain_98f61d14-ed73-4212-8352-b0e5f02f9881" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RestatementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RestatementAxis_abcc0706-5dbc-4271-98aa-96854998d5d9" xlink:to="loc_srt_RestatementDomain_98f61d14-ed73-4212-8352-b0e5f02f9881" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioPreviouslyReportedMember_0800bb83-12c6-46ff-8dfa-9438135d5c8a" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioPreviouslyReportedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RestatementDomain_98f61d14-ed73-4212-8352-b0e5f02f9881" xlink:to="loc_srt_ScenarioPreviouslyReportedMember_0800bb83-12c6-46ff-8dfa-9438135d5c8a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementAdjustmentMember_eec371f2-ca39-4fc2-ac9f-8c2f2dd3701a" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RestatementAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RestatementDomain_98f61d14-ed73-4212-8352-b0e5f02f9881" xlink:to="loc_srt_RestatementAdjustmentMember_eec371f2-ca39-4fc2-ac9f-8c2f2dd3701a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_c9bc5487-1010-4cc3-b7e1-620d56f8c03b" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_da0f9cc2-7e8b-4371-a6af-6969ec575994" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_da0f9cc2-7e8b-4371-a6af-6969ec575994" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_9c625fe8-4507-4c5d-ad98-f6beb2b7ba45" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_StockholdersEquity_9c625fe8-4507-4c5d-ad98-f6beb2b7ba45" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding_6e4877fc-a80c-47bc-97e4-a12ab78e6ccd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_PreferredStockSharesOutstanding_6e4877fc-a80c-47bc-97e4-a12ab78e6ccd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ConversionFromBusinessDevelopmentCompanyToBankChangeInPresentation_e5104174-6423-4938-8ee6-d1ea4112c4f1" xlink:href="newt-20241231.xsd#newt_ConversionFromBusinessDevelopmentCompanyToBankChangeInPresentation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_newt_ConversionFromBusinessDevelopmentCompanyToBankChangeInPresentation_e5104174-6423-4938-8ee6-d1ea4112c4f1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ConversionFromBusinessDevelopmentCompanyToBankRemovalOfFairValueAdjustments_caa274fc-6062-4bc2-baaf-82190b67f9a9" xlink:href="newt-20241231.xsd#newt_ConversionFromBusinessDevelopmentCompanyToBankRemovalOfFairValueAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_newt_ConversionFromBusinessDevelopmentCompanyToBankRemovalOfFairValueAdjustments_caa274fc-6062-4bc2-baaf-82190b67f9a9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ConversionFromBusinessDevelopmentCompanyToBankConsolidationOfInvestments_54c3806c-a6fe-4f34-b324-28e0c132eee0" xlink:href="newt-20241231.xsd#newt_ConversionFromBusinessDevelopmentCompanyToBankConsolidationOfInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_newt_ConversionFromBusinessDevelopmentCompanyToBankConsolidationOfInvestments_54c3806c-a6fe-4f34-b324-28e0c132eee0" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ConversionFromBusinessDevelopmentCompanyToBankReassessmentOfDeferredTaxAssetsAndLiabilities_18ac8de6-07ad-4d4a-a0d0-d3ef6f9fb08f" xlink:href="newt-20241231.xsd#newt_ConversionFromBusinessDevelopmentCompanyToBankReassessmentOfDeferredTaxAssetsAndLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_newt_ConversionFromBusinessDevelopmentCompanyToBankReassessmentOfDeferredTaxAssetsAndLiabilities_18ac8de6-07ad-4d4a-a0d0-d3ef6f9fb08f" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan_ffa82ed0-276c-457c-a200-ac154e6bd54c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan_ffa82ed0-276c-457c-a200-ac154e6bd54c" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan_015663e4-b3e6-4f71-9f61-3b21acdc4174" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan_015663e4-b3e6-4f71-9f61-3b21acdc4174" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_170914d0-947c-4590-8bc8-391a5e0cdda6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_170914d0-947c-4590-8bc8-391a5e0cdda6" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DividendShareBasedPaymentSharesIssued_bd16fa77-0a49-43ca-a596-5324ff0a8691" xlink:href="newt-20241231.xsd#newt_DividendShareBasedPaymentSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_newt_DividendShareBasedPaymentSharesIssued_bd16fa77-0a49-43ca-a596-5324ff0a8691" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsShareBasedCompensation_89cde014-262f-43a8-9f73-d76441bcab3b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DividendsShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_DividendsShareBasedCompensation_89cde014-262f-43a8-9f73-d76441bcab3b" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_8b464c71-63b9-42f9-b90e-4f681a6bdb11" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_8b464c71-63b9-42f9-b90e-4f681a6bdb11" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_0fdeeb5b-ada3-4ea8-a57b-1949821480f9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_0fdeeb5b-ada3-4ea8-a57b-1949821480f9" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_940b395b-0cfc-4773-81b1-03c7080b70b6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_940b395b-0cfc-4773-81b1-03c7080b70b6" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_de53c2c6-d3fa-40e8-9298-ce5059ece5d0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_de53c2c6-d3fa-40e8-9298-ce5059ece5d0" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesRetired_a9e35caa-bab4-476a-94c5-9245874ae715" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockSharesRetired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_TreasuryStockSharesRetired_a9e35caa-bab4-476a-94c5-9245874ae715" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockRetiredParValueMethodAmount_c4821f2a-6ad7-4339-a870-2321b771b24c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockRetiredParValueMethodAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_TreasuryStockRetiredParValueMethodAmount_c4821f2a-6ad7-4339-a870-2321b771b24c" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_7c94925b-4b4f-4f65-b7e2-3755ebc49df7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_7c94925b-4b4f-4f65-b7e2-3755ebc49df7" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_ad52298a-7f57-4ff7-bed5-bc67f41f82f1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_ad52298a-7f57-4ff7-bed5-bc67f41f82f1" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_63a85b36-8c46-4ea9-bfbe-f3f19d6ee6b6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_63a85b36-8c46-4ea9-bfbe-f3f19d6ee6b6" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_532a328f-8026-4940-a7ca-3b03eca5c6c2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_532a328f-8026-4940-a7ca-3b03eca5c6c2" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_b83b8335-2650-4deb-b8ff-62e2f98376d1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockDividendsPerShareDeclared"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_CommonStockDividendsPerShareDeclared_b83b8335-2650-4deb-b8ff-62e2f98376d1" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts_c56da1ee-0411-4095-a2e2-3670670c388c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts_c56da1ee-0411-4095-a2e2-3670670c388c" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStock_57c91944-1a6d-4a75-a42c-70ff3423c20c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DividendsCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_DividendsCommonStock_57c91944-1a6d-4a75-a42c-70ff3423c20c" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_AdjustmentsToAdditionalPaidInCapitalRICTaxReclassifications_d6abd7d9-2241-43d0-89b3-ca3149e5404a" xlink:href="newt-20241231.xsd#newt_AdjustmentsToAdditionalPaidInCapitalRICTaxReclassifications"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_newt_AdjustmentsToAdditionalPaidInCapitalRICTaxReclassifications_d6abd7d9-2241-43d0-89b3-ca3149e5404a" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockDividendsPerShareDeclared_665c4fc4-29f0-49e8-b32f-8d1d1711946d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockDividendsPerShareDeclared"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_PreferredStockDividendsPerShareDeclared_665c4fc4-29f0-49e8-b32f-8d1d1711946d" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsPreferredStock_0fde9be6-dbce-49f2-b19c-b7ca0a0dc312" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DividendsPreferredStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_DividendsPreferredStock_0fde9be6-dbce-49f2-b19c-b7ca0a0dc312" xlink:type="arc" order="28"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_621c45aa-cc50-4c16-b955-e055eefc71df" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_ProfitLoss_621c45aa-cc50-4c16-b955-e055eefc71df" xlink:type="arc" order="29"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_74b8bfc0-2b87-4987-9cc0-dde208829503" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_74b8bfc0-2b87-4987-9cc0-dde208829503" xlink:type="arc" order="30"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetInvestmentIncome_c9aff87b-130e-48b7-8ec7-a3425ee0debb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetInvestmentIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_NetInvestmentIncome_c9aff87b-130e-48b7-8ec7-a3425ee0debb" xlink:type="arc" order="31"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealizedGainLossInvestmentAndDerivativeOperatingAfterTax_a14b3616-a11e-4780-9712-bb96fba41f86" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RealizedGainLossInvestmentAndDerivativeOperatingAfterTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_RealizedGainLossInvestmentAndDerivativeOperatingAfterTax_a14b3616-a11e-4780-9712-bb96fba41f86" xlink:type="arc" order="32"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossInvestmentAndDerivativeOperatingAfterTax_9126db81-e06f-469d-8067-de8fb654d567" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_UnrealizedGainLossInvestmentAndDerivativeOperatingAfterTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_db950bd9-b7c8-426d-b563-fb9db40a4d07" xlink:to="loc_us-gaap_UnrealizedGainLossInvestmentAndDerivativeOperatingAfterTax_9126db81-e06f-469d-8067-de8fb654d567" xlink:type="arc" order="33"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_6c73ef4a-8e0a-4952-a4e3-86267169642e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_5a5199ec-963a-4630-a2af-f0c99b0482ed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding_d45f9f6e-d959-4f10-bb41-d478072507b2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockSharesOutstanding"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWS" xlink:type="simple" xlink:href="newt-20241231.xsd#CONSOLIDATEDSTATEMENTSOFCASHFLOWS"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_831ac5d2-7fb5-45e5-9225-b2c94e63c9f2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_96839000-b23f-4bc3-a8f0-34aa903a73b1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_831ac5d2-7fb5-45e5-9225-b2c94e63c9f2" xlink:to="loc_us-gaap_StatementTable_96839000-b23f-4bc3-a8f0-34aa903a73b1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_05170540-491f-4c66-af40-5762aa49881f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_96839000-b23f-4bc3-a8f0-34aa903a73b1" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_05170540-491f-4c66-af40-5762aa49881f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_05170540-491f-4c66-af40-5762aa49881f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_05170540-491f-4c66-af40-5762aa49881f" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_05170540-491f-4c66-af40-5762aa49881f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_370aacf9-e548-4365-a403-a79412b02733" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_05170540-491f-4c66-af40-5762aa49881f" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_370aacf9-e548-4365-a403-a79412b02733" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_4d3c4339-3872-41e2-a1c7-0d64ff3cf384" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentAffiliatedIssuerControlledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_370aacf9-e548-4365-a403-a79412b02733" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_4d3c4339-3872-41e2-a1c7-0d64ff3cf384" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_4ebaa5f6-091c-4321-81f9-6e78ef8f61ec" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_370aacf9-e548-4365-a403-a79412b02733" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_4ebaa5f6-091c-4321-81f9-6e78ef8f61ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_3d29bbd4-2745-4fe1-ac61-4834b5ec342e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_96839000-b23f-4bc3-a8f0-34aa903a73b1" xlink:to="loc_us-gaap_DebtInstrumentAxis_3d29bbd4-2745-4fe1-ac61-4834b5ec342e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_3d29bbd4-2745-4fe1-ac61-4834b5ec342e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_3d29bbd4-2745-4fe1-ac61-4834b5ec342e" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_3d29bbd4-2745-4fe1-ac61-4834b5ec342e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01dd7b72-9460-41ac-997d-769f010a99af" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_3d29bbd4-2745-4fe1-ac61-4834b5ec342e" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01dd7b72-9460-41ac-997d-769f010a99af" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2025500NotesMember_dce1176f-952c-4487-933e-ab0c9b9f6706" xlink:href="newt-20241231.xsd#newt_A2025500NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01dd7b72-9460-41ac-997d-769f010a99af" xlink:to="loc_newt_A2025500NotesMember_dce1176f-952c-4487-933e-ab0c9b9f6706" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20258125NotesMember_73422e77-5960-4ae0-9e51-26f9fd0d4edc" xlink:href="newt-20241231.xsd#newt_A20258125NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01dd7b72-9460-41ac-997d-769f010a99af" xlink:to="loc_newt_A20258125NotesMember_73422e77-5960-4ae0-9e51-26f9fd0d4edc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2028NotesMember_29e218cf-2a19-4fcc-ba2a-85f230a42efe" xlink:href="newt-20241231.xsd#newt_A2028NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01dd7b72-9460-41ac-997d-769f010a99af" xlink:to="loc_newt_A2028NotesMember_29e218cf-2a19-4fcc-ba2a-85f230a42efe" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2024NotesMember_11b10657-7c3d-46ba-abbf-31f089b592df" xlink:href="newt-20241231.xsd#newt_A2024NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01dd7b72-9460-41ac-997d-769f010a99af" xlink:to="loc_newt_A2024NotesMember_11b10657-7c3d-46ba-abbf-31f089b592df" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2025685NotesMember_06673e67-c3c1-4131-81fd-e32b33697027" xlink:href="newt-20241231.xsd#newt_A2025685NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01dd7b72-9460-41ac-997d-769f010a99af" xlink:to="loc_newt_A2025685NotesMember_06673e67-c3c1-4131-81fd-e32b33697027" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.50NotesMember_ba022b0d-4685-4300-bd34-167edab2c38b" xlink:href="newt-20241231.xsd#newt_A20298.50NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01dd7b72-9460-41ac-997d-769f010a99af" xlink:to="loc_newt_A20298.50NotesMember_ba022b0d-4685-4300-bd34-167edab2c38b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.625NotesMember_258d0135-028b-4b53-bbde-49233b3ba033" xlink:href="newt-20241231.xsd#newt_A20298.625NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01dd7b72-9460-41ac-997d-769f010a99af" xlink:to="loc_newt_A20298.625NotesMember_258d0135-028b-4b53-bbde-49233b3ba033" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_b0e70ddd-892b-45d1-a3d5-85f7cb1c397e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_831ac5d2-7fb5-45e5-9225-b2c94e63c9f2" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_b0e70ddd-892b-45d1-a3d5-85f7cb1c397e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_4aa18916-58ce-4bbd-9431-b4c46312705c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_b0e70ddd-892b-45d1-a3d5-85f7cb1c397e" xlink:to="loc_us-gaap_NetIncomeLoss_4aa18916-58ce-4bbd-9431-b4c46312705c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:href="newt-20241231.xsd#newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_b0e70ddd-892b-45d1-a3d5-85f7cb1c397e" xlink:to="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss_97d2e342-79cd-459c-8080-a2401890ba3a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss_97d2e342-79cd-459c-8080-a2401890ba3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_UnrealizedGainLossOnSalesOfLoansNetFairValueOption_a7d8593a-f659-4049-aec0-629407c34262" xlink:href="newt-20241231.xsd#newt_UnrealizedGainLossOnSalesOfLoansNetFairValueOption"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_newt_UnrealizedGainLossOnSalesOfLoansNetFairValueOption_a7d8593a-f659-4049-aec0-629407c34262" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_UnrealizedGainLossOnServicingAssets_0f5a54ca-2ca8-49d7-b04f-dc856a506d07" xlink:href="newt-20241231.xsd#newt_UnrealizedGainLossOnServicingAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_newt_UnrealizedGainLossOnServicingAssets_0f5a54ca-2ca8-49d7-b04f-dc856a506d07" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_20bfb69b-5a70-43c9-81ab-f03cd414ea24" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_20bfb69b-5a70-43c9-81ab-f03cd414ea24" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_GainLossOnAssetsClassifiedAsHeldForSale_affd3de4-0f57-4def-b95d-ff60562b7565" xlink:href="newt-20241231.xsd#newt_GainLossOnAssetsClassifiedAsHeldForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_newt_GainLossOnAssetsClassifiedAsHeldForSale_affd3de4-0f57-4def-b95d-ff60562b7565" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSalesOfLoansNet_b4ed11d4-7f6f-45c5-ba7f-0645174754c5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainLossOnSalesOfLoansNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_GainLossOnSalesOfLoansNet_b4ed11d4-7f6f-45c5-ba7f-0645174754c5" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_a63918c5-7e4e-4713-aa0b-f62b6c2537cf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_a63918c5-7e4e-4713-aa0b-f62b6c2537cf" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_2eab1132-f39d-4b3f-a079-e32e1e7d5e61" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_2eab1132-f39d-4b3f-a079-e32e1e7d5e61" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_7d3e67bb-7964-441b-9336-7477a33e1e6f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AmortizationOfFinancingCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_7d3e67bb-7964-441b-9336-7477a33e1e6f" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForLoanLossesExpensed_ed00aaba-95c2-4ce4-a9dd-8bb81b7424f2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProvisionForLoanLossesExpensed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_ProvisionForLoanLossesExpensed_ed00aaba-95c2-4ce4-a9dd-8bb81b7424f2" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LowerOfCostOrMarketAdjustment_41d6ede5-3874-4bc1-b0ad-45236d06cd02" xlink:href="newt-20241231.xsd#newt_LowerOfCostOrMarketAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_newt_LowerOfCostOrMarketAdjustment_41d6ede5-3874-4bc1-b0ad-45236d06cd02" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForDoubtfulAccounts_ef20950a-8811-41ec-b4de-37c045bff826" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProvisionForDoubtfulAccounts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_ProvisionForDoubtfulAccounts_ef20950a-8811-41ec-b4de-37c045bff826" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_63e3d842-3f7a-4b7b-8d27-5c682d0f301e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_ShareBasedCompensation_63e3d842-3f7a-4b7b-8d27-5c682d0f301e" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_ef4aaa33-df47-404a-9184-f7736b7f62a8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_ef4aaa33-df47-404a-9184-f7736b7f62a8" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_2f1c29e9-bd83-4162-8804-63a858511103" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_2f1c29e9-bd83-4162-8804-63a858511103" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfLoansHeldForSale_37810973-efd6-4461-93d7-db09e90d6652" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromSaleOfLoansHeldForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_ProceedsFromSaleOfLoansHeldForSale_37810973-efd6-4461-93d7-db09e90d6652" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToPurchaseLoansHeldForSale_520530de-4a34-4bbd-b699-683236027db9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToPurchaseLoansHeldForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_PaymentsToPurchaseLoansHeldForSale_520530de-4a34-4bbd-b699-683236027db9" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ProceedsFromSalePaymentsForPurchaseOfLoans_c123a748-8ae8-48b5-b639-bda4291f0a6a" xlink:href="newt-20241231.xsd#newt_ProceedsFromSalePaymentsForPurchaseOfLoans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_newt_ProceedsFromSalePaymentsForPurchaseOfLoans_c123a748-8ae8-48b5-b639-bda4291f0a6a" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PaymentsForFundingOfLoansHeldForSale_4f7d318d-5fb1-4ae9-9a0d-1c05770140e4" xlink:href="newt-20241231.xsd#newt_PaymentsForFundingOfLoansHeldForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_newt_PaymentsForFundingOfLoansHeldForSale_4f7d318d-5fb1-4ae9-9a0d-1c05770140e4" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PaymentsForFundingOfInvestmentOperatingActivity_16258653-0d1c-46c1-944b-a9861876b95b" xlink:href="newt-20241231.xsd#newt_PaymentsForFundingOfInvestmentOperatingActivity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_newt_PaymentsForFundingOfInvestmentOperatingActivity_16258653-0d1c-46c1-944b-a9861876b95b" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ProceedsFromPrincipalReceivedOnLoansHeldForSale_c326099e-2527-422b-bcdb-f769f571a40b" xlink:href="newt-20241231.xsd#newt_ProceedsFromPrincipalReceivedOnLoansHeldForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_newt_ProceedsFromPrincipalReceivedOnLoansHeldForSale_c326099e-2527-422b-bcdb-f769f571a40b" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ProceedsFromPrincipalReceivedOnInvestments_a743fc40-cafb-4e90-8186-304958d17d95" xlink:href="newt-20241231.xsd#newt_ProceedsFromPrincipalReceivedOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_newt_ProceedsFromPrincipalReceivedOnInvestments_a743fc40-cafb-4e90-8186-304958d17d95" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentDividendsOrDistributions_0cd613a4-e79f-49da-a87e-9cf72cdf7c10" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityMethodInvestmentDividendsOrDistributions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_EquityMethodInvestmentDividendsOrDistributions_0cd613a4-e79f-49da-a87e-9cf72cdf7c10" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNoncashIncomeExpense_af7b6bb5-4af6-4cb8-b20d-2a074d32c280" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherNoncashIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_OtherNoncashIncomeExpense_af7b6bb5-4af6-4cb8-b20d-2a074d32c280" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_AdjustmentsToReconcileNetAssetsFromOperationsToCashProvidedByUsedInOperatingActivitiesAbstract_a9a69d4d-ad25-4cb2-bbbd-1108f53d225b" xlink:to="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInBrokerageReceivables_56207406-e66c-455b-8666-f98c3bbd2c21" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInBrokerageReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_us-gaap_IncreaseDecreaseInBrokerageReceivables_56207406-e66c-455b-8666-f98c3bbd2c21" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_3b86c3c7-6ce6-48d9-8ea1-53a20fec0e9a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_3b86c3c7-6ce6-48d9-8ea1-53a20fec0e9a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInDividendsReceivable_962984d8-1b39-4c84-85ee-8a0de2d7a026" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInDividendsReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_us-gaap_IncreaseDecreaseInDividendsReceivable_962984d8-1b39-4c84-85ee-8a0de2d7a026" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_IncreaseDecreaseInDueFromDueToRelatedParties_e49839be-284b-44d9-a652-8e1dbba2ecff" xlink:href="newt-20241231.xsd#newt_IncreaseDecreaseInDueFromDueToRelatedParties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_newt_IncreaseDecreaseInDueFromDueToRelatedParties_e49839be-284b-44d9-a652-8e1dbba2ecff" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_d7cd8402-0ca3-4551-b9a9-51954efe043b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInOtherOperatingAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_d7cd8402-0ca3-4551-b9a9-51954efe043b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAssetsHeldForSale_b41527c5-73eb-4dd8-b8ae-c5904929f9a3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInAssetsHeldForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_us-gaap_IncreaseDecreaseInAssetsHeldForSale_b41527c5-73eb-4dd8-b8ae-c5904929f9a3" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_IncreaseDecreaseInLiabilityHeldForSale_ad3ca9c8-4425-437f-bace-3be9278cbbb4" xlink:href="newt-20241231.xsd#newt_IncreaseDecreaseInLiabilityHeldForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_newt_IncreaseDecreaseInLiabilityHeldForSale_ad3ca9c8-4425-437f-bace-3be9278cbbb4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_IncreaseDecreaseInDividendsPayable_223f918e-06e8-4f0b-83d0-e97cef6c9a70" xlink:href="newt-20241231.xsd#newt_IncreaseDecreaseInDividendsPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_newt_IncreaseDecreaseInDividendsPayable_223f918e-06e8-4f0b-83d0-e97cef6c9a70" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_IncreaseDecreaseInDueToParticipants_8659cafb-de47-4142-93aa-77cd812af819" xlink:href="newt-20241231.xsd#newt_IncreaseDecreaseInDueToParticipants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_newt_IncreaseDecreaseInDueToParticipants_8659cafb-de47-4142-93aa-77cd812af819" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_e76fd3bd-8385-457d-a20f-4d0965a7ccc1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_e76fd3bd-8385-457d-a20f-4d0965a7ccc1" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_fa78aec3-9f26-4219-9175-5cfb0800778c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInOtherOperatingLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_8a94b7c6-d7da-4b4e-8ead-6ee720fe505a" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_fa78aec3-9f26-4219-9175-5cfb0800778c" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_aadb3c4f-b837-40b4-b44a-6912bcb7d721" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_b0e70ddd-892b-45d1-a3d5-85f7cb1c397e" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_aadb3c4f-b837-40b4-b44a-6912bcb7d721" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_831ac5d2-7fb5-45e5-9225-b2c94e63c9f2" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PaymentsToAcquireLoansHeldForInvestmentAtFairValue_8d8dfffc-7a4a-461c-b72b-8d38bf5c6258" xlink:href="newt-20241231.xsd#newt_PaymentsToAcquireLoansHeldForInvestmentAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:to="loc_newt_PaymentsToAcquireLoansHeldForInvestmentAtFairValue_8d8dfffc-7a4a-461c-b72b-8d38bf5c6258" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ProceedsFromLoansHeldForInvestmentAtCost_e2d04595-24de-480f-8ced-7fcd1a017af5" xlink:href="newt-20241231.xsd#newt_ProceedsFromLoansHeldForInvestmentAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:to="loc_newt_ProceedsFromLoansHeldForInvestmentAtCost_e2d04595-24de-480f-8ced-7fcd1a017af5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PaymentsForContributionsToJointVenturesAndNoncontrolledInvestments_89fbe464-1574-4186-8858-e7d50aa690a5" xlink:href="newt-20241231.xsd#newt_PaymentsForContributionsToJointVenturesAndNoncontrolledInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:to="loc_newt_PaymentsForContributionsToJointVenturesAndNoncontrolledInvestments_89fbe464-1574-4186-8858-e7d50aa690a5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital_d19b0278-01ef-4b6d-8eae-d1c8f6cd5fcc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:to="loc_us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital_d19b0278-01ef-4b6d-8eae-d1c8f6cd5fcc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_b043bba1-28ef-4627-91c0-a1a6272c9ebe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_b043bba1-28ef-4627-91c0-a1a6272c9ebe" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInLoansToFederalHomeLoanBanks_6da994fc-cd16-4952-a340-5ee56b2cd51c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInLoansToFederalHomeLoanBanks"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:to="loc_us-gaap_IncreaseDecreaseInLoansToFederalHomeLoanBanks_6da994fc-cd16-4952-a340-5ee56b2cd51c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_8f1b44d5-e121-4d3f-8e97-a033b3338402" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:to="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_8f1b44d5-e121-4d3f-8e97-a033b3338402" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_4bcea20d-23f5-4a3e-80f5-beee89d3e081" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:to="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_4bcea20d-23f5-4a3e-80f5-beee89d3e081" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_b0c3a74f-3c11-4f5c-8196-273b1298d890" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_b0c3a74f-3c11-4f5c-8196-273b1298d890" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_19bccab3-a0f3-4149-8d4b-4b7d95734feb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_c4863dfa-eb3a-4f4e-adad-c5dd63dcbf76" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_19bccab3-a0f3-4149-8d4b-4b7d95734feb" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_831ac5d2-7fb5-45e5-9225-b2c94e63c9f2" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromRepaymentsOfNotesPayable_04931ac8-a53c-4aa5-8ffc-85c3e8c72c18" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromRepaymentsOfNotesPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_ProceedsFromRepaymentsOfNotesPayable_04931ac8-a53c-4aa5-8ffc-85c3e8c72c18" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_IncreaseDecreaseInDepositLiabilities_b7135264-0960-4e6f-9032-8a513ea7dae9" xlink:href="newt-20241231.xsd#newt_IncreaseDecreaseInDepositLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_newt_IncreaseDecreaseInDepositLiabilities_b7135264-0960-4e6f-9032-8a513ea7dae9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_RepaymentOfFederalHomeLoanBankAdvances_da968554-50a5-4680-b2fb-44175b60a7f1" xlink:href="newt-20241231.xsd#newt_RepaymentOfFederalHomeLoanBankAdvances"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_newt_RepaymentOfFederalHomeLoanBankAdvances_da968554-50a5-4680-b2fb-44175b60a7f1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_3986ad6a-ee04-44eb-b26e-570158dded39" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_3986ad6a-ee04-44eb-b26e-570158dded39" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfPreferredStockAndPreferenceStock_f12735e6-2793-43eb-97eb-4e4dd2bc4c8c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromIssuanceOfPreferredStockAndPreferenceStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfPreferredStockAndPreferenceStock_f12735e6-2793-43eb-97eb-4e4dd2bc4c8c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromRepaymentsOfRelatedPartyDebt_47df8d7a-ab84-4d7b-a619-019e230c5b60" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromRepaymentsOfRelatedPartyDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_ProceedsFromRepaymentsOfRelatedPartyDebt_47df8d7a-ab84-4d7b-a619-019e230c5b60" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfMediumTermNotes_926a3b9b-6f74-49ec-a0b8-5cbacd15c506" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromIssuanceOfMediumTermNotes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfMediumTermNotes_926a3b9b-6f74-49ec-a0b8-5cbacd15c506" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfMediumTermNotes_4e61446b-30e8-40eb-8e79-6dc6ae2c36bd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RepaymentsOfMediumTermNotes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_RepaymentsOfMediumTermNotes_4e61446b-30e8-40eb-8e79-6dc6ae2c36bd" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfSecuredDebt_f910e56e-16e6-4dd6-95fb-ecb069832e34" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RepaymentsOfSecuredDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_RepaymentsOfSecuredDebt_f910e56e-16e6-4dd6-95fb-ecb069832e34" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfSecuredDebt_d4b8898f-5527-4076-ae4e-c2581d656c9b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromIssuanceOfSecuredDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfSecuredDebt_d4b8898f-5527-4076-ae4e-c2581d656c9b" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividends_0751cb4f-555c-48e2-988e-4ee9cade84a4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsOfDividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_PaymentsOfDividends_0751cb4f-555c-48e2-988e-4ee9cade84a4" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PaymentsOfDeferredFinancingCosts_af15f4f3-5ad7-450a-be76-a5afb0baabe9" xlink:href="newt-20241231.xsd#newt_PaymentsOfDeferredFinancingCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_newt_PaymentsOfDeferredFinancingCosts_af15f4f3-5ad7-450a-be76-a5afb0baabe9" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromStockPlans_82efdc3c-e911-4c15-b395-fef50eed5d17" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromStockPlans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_ProceedsFromStockPlans_82efdc3c-e911-4c15-b395-fef50eed5d17" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_94234648-22b8-40c7-a1b0-f40fef362bbd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_94234648-22b8-40c7-a1b0-f40fef362bbd" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_69f3076a-1179-4bfe-b0ee-aeb20cdf45fc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_69f3076a-1179-4bfe-b0ee-aeb20cdf45fc" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_1dc74207-fe7a-4cdb-95cc-c3e8899defc7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_39041e76-b2bc-4e0a-a598-d733d29f6f39" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_1dc74207-fe7a-4cdb-95cc-c3e8899defc7" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_d3f289c4-b710-49a8-b527-274aa53ab79d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_831ac5d2-7fb5-45e5-9225-b2c94e63c9f2" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_d3f289c4-b710-49a8-b527-274aa53ab79d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_0aa93ce9-ee4f-4874-8044-4b889bd637b0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_831ac5d2-7fb5-45e5-9225-b2c94e63c9f2" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_0aa93ce9-ee4f-4874-8044-4b889bd637b0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ConsolidationDeconsolidationOfCashAndRestrictedCashFromInvestments_1195d039-9ddf-4131-ab50-907fdd1d7c16" xlink:href="newt-20241231.xsd#newt_ConsolidationDeconsolidationOfCashAndRestrictedCashFromInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_831ac5d2-7fb5-45e5-9225-b2c94e63c9f2" xlink:to="loc_newt_ConsolidationDeconsolidationOfCashAndRestrictedCashFromInvestments_1195d039-9ddf-4131-ab50-907fdd1d7c16" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_465cef76-c4aa-43c8-8c21-f0931616f78b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_9ddd5902-b611-455b-a3c2-e9361966977d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_831ac5d2-7fb5-45e5-9225-b2c94e63c9f2" xlink:to="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_9ddd5902-b611-455b-a3c2-e9361966977d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransferOfOtherRealEstate_60bff83c-7e8b-4e20-b973-c848d3c67395" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransferOfOtherRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_9ddd5902-b611-455b-a3c2-e9361966977d" xlink:to="loc_us-gaap_TransferOfOtherRealEstate_60bff83c-7e8b-4e20-b973-c848d3c67395" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DividendsIncurredButNotYetPaid_f327ca9f-c39f-4ac1-b173-55853eae6978" xlink:href="newt-20241231.xsd#newt_DividendsIncurredButNotYetPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_9ddd5902-b611-455b-a3c2-e9361966977d" xlink:to="loc_newt_DividendsIncurredButNotYetPaid_f327ca9f-c39f-4ac1-b173-55853eae6978" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssued1_5b56002f-8f68-47c3-8bf3-9fab67cd4bdc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssued1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_9ddd5902-b611-455b-a3c2-e9361966977d" xlink:to="loc_us-gaap_StockIssued1_5b56002f-8f68-47c3-8bf3-9fab67cd4bdc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplementalCashFlowInformationAbstract_0a0c0cac-946a-4833-8992-12693ae24ab2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SupplementalCashFlowInformationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_831ac5d2-7fb5-45e5-9225-b2c94e63c9f2" xlink:to="loc_us-gaap_SupplementalCashFlowInformationAbstract_0a0c0cac-946a-4833-8992-12693ae24ab2" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestPaidNet_a1a46e4d-6a6a-4960-8416-24b458a2bfc7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestPaidNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SupplementalCashFlowInformationAbstract_0a0c0cac-946a-4833-8992-12693ae24ab2" xlink:to="loc_us-gaap_InterestPaidNet_a1a46e4d-6a6a-4960-8416-24b458a2bfc7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxesPaidNet_8236cc0c-a5d5-48a4-bf7a-0892ee0fc49a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxesPaidNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SupplementalCashFlowInformationAbstract_0a0c0cac-946a-4833-8992-12693ae24ab2" xlink:to="loc_us-gaap_IncomeTaxesPaidNet_8236cc0c-a5d5-48a4-bf7a-0892ee0fc49a" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSParenthetical" xlink:type="simple" xlink:href="newt-20241231.xsd#CONSOLIDATEDSTATEMENTSOFCASHFLOWSParenthetical"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_bb8109e5-8983-42e9-98e3-9a54fc6abea6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_10d6f2b8-3d62-4346-a326-c06396815177" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_bb8109e5-8983-42e9-98e3-9a54fc6abea6" xlink:to="loc_us-gaap_StatementTable_10d6f2b8-3d62-4346-a326-c06396815177" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_d14a7a85-98b8-4454-b177-f7f07fc9869a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_10d6f2b8-3d62-4346-a326-c06396815177" xlink:to="loc_us-gaap_DebtInstrumentAxis_d14a7a85-98b8-4454-b177-f7f07fc9869a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_d14a7a85-98b8-4454-b177-f7f07fc9869a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_d14a7a85-98b8-4454-b177-f7f07fc9869a" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_d14a7a85-98b8-4454-b177-f7f07fc9869a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_df69ce43-9ef5-4a4f-9450-8a72e193a81b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_d14a7a85-98b8-4454-b177-f7f07fc9869a" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_df69ce43-9ef5-4a4f-9450-8a72e193a81b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2025500NotesMember_f87840b0-6eca-4e10-b1d9-00527cc54bb1" xlink:href="newt-20241231.xsd#newt_A2025500NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_df69ce43-9ef5-4a4f-9450-8a72e193a81b" xlink:to="loc_newt_A2025500NotesMember_f87840b0-6eca-4e10-b1d9-00527cc54bb1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20258125NotesMember_73133e91-1488-4893-a48c-1b9a414fe85f" xlink:href="newt-20241231.xsd#newt_A20258125NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_df69ce43-9ef5-4a4f-9450-8a72e193a81b" xlink:to="loc_newt_A20258125NotesMember_73133e91-1488-4893-a48c-1b9a414fe85f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2028NotesMember_08274ec7-abb4-436d-a40e-42ab6fe654c5" xlink:href="newt-20241231.xsd#newt_A2028NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_df69ce43-9ef5-4a4f-9450-8a72e193a81b" xlink:to="loc_newt_A2028NotesMember_08274ec7-abb4-436d-a40e-42ab6fe654c5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2025685NotesMember_53e431fc-50f5-41b6-aff7-45efd3aae508" xlink:href="newt-20241231.xsd#newt_A2025685NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_df69ce43-9ef5-4a4f-9450-8a72e193a81b" xlink:to="loc_newt_A2025685NotesMember_53e431fc-50f5-41b6-aff7-45efd3aae508" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.50NotesMember_6eb24e2f-af54-475f-8c25-c6b14be05877" xlink:href="newt-20241231.xsd#newt_A20298.50NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_df69ce43-9ef5-4a4f-9450-8a72e193a81b" xlink:to="loc_newt_A20298.50NotesMember_6eb24e2f-af54-475f-8c25-c6b14be05877" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.625NotesMember_6148eba6-129c-411e-8c0a-30fe453a5bb9" xlink:href="newt-20241231.xsd#newt_A20298.625NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_df69ce43-9ef5-4a4f-9450-8a72e193a81b" xlink:to="loc_newt_A20298.625NotesMember_6148eba6-129c-411e-8c0a-30fe453a5bb9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_4e8012e5-8cd2-48e5-b9f2-0bc2d1383e6b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_10d6f2b8-3d62-4346-a326-c06396815177" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_4e8012e5-8cd2-48e5-b9f2-0bc2d1383e6b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_4e8012e5-8cd2-48e5-b9f2-0bc2d1383e6b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_4e8012e5-8cd2-48e5-b9f2-0bc2d1383e6b" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_4e8012e5-8cd2-48e5-b9f2-0bc2d1383e6b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_d2f2bdeb-c76b-46d7-b4dc-0bb9d09eb61f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_4e8012e5-8cd2-48e5-b9f2-0bc2d1383e6b" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_d2f2bdeb-c76b-46d7-b4dc-0bb9d09eb61f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MediumTermNotesMember_231531a9-0a9d-4150-b5e9-36708737d20e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MediumTermNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_d2f2bdeb-c76b-46d7-b4dc-0bb9d09eb61f" xlink:to="loc_us-gaap_MediumTermNotesMember_231531a9-0a9d-4150-b5e9-36708737d20e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_f4fa9279-406c-410e-a900-89847ba81dc0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtWeightedAverageInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_bb8109e5-8983-42e9-98e3-9a54fc6abea6" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_f4fa9279-406c-410e-a900-89847ba81dc0" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/SIGNIFICANTACCOUNTINGPOLICIESNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#SIGNIFICANTACCOUNTINGPOLICIESNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/SIGNIFICANTACCOUNTINGPOLICIESNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_f1d7d4e9-42f0-46c8-85bf-abc9f4ea7968" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_f1d7d4e9-42f0-46c8-85bf-abc9f4ea7968" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_a852bc11-e1f1-41ed-8511-20b9dd48f21e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_f1d7d4e9-42f0-46c8-85bf-abc9f4ea7968" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_a852bc11-e1f1-41ed-8511-20b9dd48f21e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_a852bc11-e1f1-41ed-8511-20b9dd48f21e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_a852bc11-e1f1-41ed-8511-20b9dd48f21e" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_a852bc11-e1f1-41ed-8511-20b9dd48f21e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_0f657276-8f65-4114-b3ad-63e947c967c7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_a852bc11-e1f1-41ed-8511-20b9dd48f21e" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_0f657276-8f65-4114-b3ad-63e947c967c7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanMember_b7cbe139-d881-4cd1-9c6a-ce81934bee03" xlink:href="newt-20241231.xsd#newt_SBA7aLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_0f657276-8f65-4114-b3ad-63e947c967c7" xlink:to="loc_newt_SBA7aLoanMember_b7cbe139-d881-4cd1-9c6a-ce81934bee03" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_9ca1158c-6ef3-4142-a53b-7e08cb8af406" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_f1d7d4e9-42f0-46c8-85bf-abc9f4ea7968" xlink:to="loc_srt_RangeAxis_9ca1158c-6ef3-4142-a53b-7e08cb8af406" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_9ca1158c-6ef3-4142-a53b-7e08cb8af406_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_9ca1158c-6ef3-4142-a53b-7e08cb8af406" xlink:to="loc_srt_RangeMember_9ca1158c-6ef3-4142-a53b-7e08cb8af406_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_24c76057-f775-43a2-9acd-61e48ed37ab3" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_9ca1158c-6ef3-4142-a53b-7e08cb8af406" xlink:to="loc_srt_RangeMember_24c76057-f775-43a2-9acd-61e48ed37ab3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_7dba2e9c-cbcf-4f21-a5a5-0a11b2cc4d25" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_24c76057-f775-43a2-9acd-61e48ed37ab3" xlink:to="loc_srt_MaximumMember_7dba2e9c-cbcf-4f21-a5a5-0a11b2cc4d25" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_64096d7d-9ccb-426a-99f0-edac3bba884d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_f1d7d4e9-42f0-46c8-85bf-abc9f4ea7968" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_64096d7d-9ccb-426a-99f0-edac3bba884d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_64096d7d-9ccb-426a-99f0-edac3bba884d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_64096d7d-9ccb-426a-99f0-edac3bba884d" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_64096d7d-9ccb-426a-99f0-edac3bba884d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_544a29e1-3232-4cf3-a86b-ac1c4b4ab255" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_64096d7d-9ccb-426a-99f0-edac3bba884d" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_544a29e1-3232-4cf3-a86b-ac1c4b4ab255" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CustomerMerchantAccountsMember_4a596d43-182f-4c65-8ca8-dedcb249f5e7" xlink:href="newt-20241231.xsd#newt_CustomerMerchantAccountsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_544a29e1-3232-4cf3-a86b-ac1c4b4ab255" xlink:to="loc_newt_CustomerMerchantAccountsMember_4a596d43-182f-4c65-8ca8-dedcb249f5e7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashUninsuredAmount_d5c99812-3f68-460f-9317-39a426250633" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashUninsuredAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_us-gaap_CashUninsuredAmount_d5c99812-3f68-460f-9317-39a426250633" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCash_7b3910ca-7e12-42ac-8a80-fdc8eba8ce8b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_us-gaap_RestrictedCash_7b3910ca-7e12-42ac-8a80-fdc8eba8ce8b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableWeightedAverageLife_b9494a11-6b17-4ea4-8148-8a9d96cddacd" xlink:href="newt-20241231.xsd#newt_FinancingReceivableWeightedAverageLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_newt_FinancingReceivableWeightedAverageLife_b9494a11-6b17-4ea4-8148-8a9d96cddacd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableLoanToValueRatio_b3420afb-ff65-430f-9626-68ed02eba687" xlink:href="newt-20241231.xsd#newt_FinancingReceivableLoanToValueRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_newt_FinancingReceivableLoanToValueRatio_b3420afb-ff65-430f-9626-68ed02eba687" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtInstrumentServiceCoverageRatioMinimum_771403d7-a379-40cd-aa05-c2982498a2dd" xlink:href="newt-20241231.xsd#newt_DebtInstrumentServiceCoverageRatioMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_newt_DebtInstrumentServiceCoverageRatioMinimum_771403d7-a379-40cd-aa05-c2982498a2dd" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableSale_05967bec-39e2-4cf4-90f3-4eadbfb7c6a0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_us-gaap_FinancingReceivableSale_05967bec-39e2-4cf4-90f3-4eadbfb7c6a0" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableUnamortizedPurchasePremiumDiscount_2e62ecf6-44e8-43a8-ba25-d04bf9634972" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableUnamortizedPurchasePremiumDiscount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_us-gaap_FinancingReceivableUnamortizedPurchasePremiumDiscount_2e62ecf6-44e8-43a8-ba25-d04bf9634972" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_f6bcfaa1-016f-49cb-b709-20567793d0b4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_f6bcfaa1-016f-49cb-b709-20567793d0b4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseRemainingLeaseTerm_6d0df0cc-e227-4277-b84d-cd3dd0ca0465" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LesseeOperatingLeaseRemainingLeaseTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_us-gaap_LesseeOperatingLeaseRemainingLeaseTerm_6d0df0cc-e227-4277-b84d-cd3dd0ca0465" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseRenewalTerm_f5aeda98-2f22-4227-bde2-12748ae2a325" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LesseeOperatingLeaseRenewalTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_us-gaap_LesseeOperatingLeaseRenewalTerm_f5aeda98-2f22-4227-bde2-12748ae2a325" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NumberOfLoanSecuritizations_cbcd12d0-3657-4dd1-a7bc-a37b51809283" xlink:href="newt-20241231.xsd#newt_NumberOfLoanSecuritizations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_newt_NumberOfLoanSecuritizations_cbcd12d0-3657-4dd1-a7bc-a37b51809283" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportableSegments_ed07585a-8e2e-4bb5-afd5-4d8882253d97" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NumberOfReportableSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ca5941be-f500-4aac-b429-fb45bc6d1cce" xlink:to="loc_us-gaap_NumberOfReportableSegments_ed07585a-8e2e-4bb5-afd5-4d8882253d97" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BUSINESSCOMBINATIONSNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BUSINESSCOMBINATIONSNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BUSINESSCOMBINATIONSNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_c7ad7451-3f13-49cd-a876-6401a711201d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_3f525d01-cf11-490c-a8a2-8ad14910545e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_c7ad7451-3f13-49cd-a876-6401a711201d" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_3f525d01-cf11-490c-a8a2-8ad14910545e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_0a15f7ff-5f2e-4763-98a8-34b947ebeea7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_3f525d01-cf11-490c-a8a2-8ad14910545e" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_0a15f7ff-5f2e-4763-98a8-34b947ebeea7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_0a15f7ff-5f2e-4763-98a8-34b947ebeea7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_0a15f7ff-5f2e-4763-98a8-34b947ebeea7" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_0a15f7ff-5f2e-4763-98a8-34b947ebeea7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_0f61bb8d-ec7e-4712-8a42-79aceae3ef43" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_0a15f7ff-5f2e-4763-98a8-34b947ebeea7" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_0f61bb8d-ec7e-4712-8a42-79aceae3ef43" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NationalBankOfNewYorkCityMember_742c39c5-069e-465d-ae9d-346da52a7804" xlink:href="newt-20241231.xsd#newt_NationalBankOfNewYorkCityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_0f61bb8d-ec7e-4712-8a42-79aceae3ef43" xlink:to="loc_newt_NationalBankOfNewYorkCityMember_742c39c5-069e-465d-ae9d-346da52a7804" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_543606d4-7029-4bbf-aeba-2d76719d9956" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_3f525d01-cf11-490c-a8a2-8ad14910545e" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_543606d4-7029-4bbf-aeba-2d76719d9956" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_543606d4-7029-4bbf-aeba-2d76719d9956_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_543606d4-7029-4bbf-aeba-2d76719d9956" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_543606d4-7029-4bbf-aeba-2d76719d9956_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_eaba5c14-0c5f-4990-a399-38d94c74425c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_543606d4-7029-4bbf-aeba-2d76719d9956" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_eaba5c14-0c5f-4990-a399-38d94c74425c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CoreDepositsMember_7862c417-332e-4b01-a263-d63526c93f37" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CoreDepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_eaba5c14-0c5f-4990-a399-38d94c74425c" xlink:to="loc_us-gaap_CoreDepositsMember_7862c417-332e-4b01-a263-d63526c93f37" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_f0f63747-1b99-46c8-8fd2-f969a498b78e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_c7ad7451-3f13-49cd-a876-6401a711201d" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_f0f63747-1b99-46c8-8fd2-f969a498b78e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_deb4e2c3-a535-4d38-a526-688af85bbc74" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationAcquisitionRelatedCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_c7ad7451-3f13-49cd-a876-6401a711201d" xlink:to="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_deb4e2c3-a535-4d38-a526-688af85bbc74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDistributionsToAffiliates_66ee03f7-158a-4103-8f91-f155af2b974a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsOfDistributionsToAffiliates"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_c7ad7451-3f13-49cd-a876-6401a711201d" xlink:to="loc_us-gaap_PaymentsOfDistributionsToAffiliates_66ee03f7-158a-4103-8f91-f155af2b974a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_f8b76ff8-5802-41f8-8d45-7b7c95a7966b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_c7ad7451-3f13-49cd-a876-6401a711201d" xlink:to="loc_us-gaap_Goodwill_f8b76ff8-5802-41f8-8d45-7b7c95a7966b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillPurchaseAccountingAdjustments_73c920e2-bd55-4c73-bbc1-fa61efbd1e57" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillPurchaseAccountingAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_c7ad7451-3f13-49cd-a876-6401a711201d" xlink:to="loc_us-gaap_GoodwillPurchaseAccountingAdjustments_73c920e2-bd55-4c73-bbc1-fa61efbd1e57" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_57de036e-bf57-4178-8d5b-35b971c608f7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_c7ad7451-3f13-49cd-a876-6401a711201d" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_57de036e-bf57-4178-8d5b-35b971c608f7" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts_199e8ee2-e0bc-46b4-8b5a-9ea7202ebd4d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_c7ad7451-3f13-49cd-a876-6401a711201d" xlink:to="loc_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts_199e8ee2-e0bc-46b4-8b5a-9ea7202ebd4d" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BUSINESSCOMBINATIONSPurchasePriceDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BUSINESSCOMBINATIONSPurchasePriceDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BUSINESSCOMBINATIONSPurchasePriceDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_028a7448-f6e4-467b-85b2-dff33e8771fa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_bc4ddfba-8fd0-4a78-9047-0a4add25ba43" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_028a7448-f6e4-467b-85b2-dff33e8771fa" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_bc4ddfba-8fd0-4a78-9047-0a4add25ba43" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_f55b95b3-4c01-4973-8208-6bd325e64be1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_bc4ddfba-8fd0-4a78-9047-0a4add25ba43" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_f55b95b3-4c01-4973-8208-6bd325e64be1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f55b95b3-4c01-4973-8208-6bd325e64be1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_f55b95b3-4c01-4973-8208-6bd325e64be1" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f55b95b3-4c01-4973-8208-6bd325e64be1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_81485ce6-434b-4d54-a1b7-de0e54798fec" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_f55b95b3-4c01-4973-8208-6bd325e64be1" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_81485ce6-434b-4d54-a1b7-de0e54798fec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NationalBankOfNewYorkCityMember_d3c9dd32-afd9-41ca-a98f-cef31d866afd" xlink:href="newt-20241231.xsd#newt_NationalBankOfNewYorkCityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_81485ce6-434b-4d54-a1b7-de0e54798fec" xlink:to="loc_newt_NationalBankOfNewYorkCityMember_d3c9dd32-afd9-41ca-a98f-cef31d866afd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationPriceOfAcquisitionExpected_bec54635-fb82-4f28-8b84-d0be16084180" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationPriceOfAcquisitionExpected"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_028a7448-f6e4-467b-85b2-dff33e8771fa" xlink:to="loc_us-gaap_BusinessCombinationPriceOfAcquisitionExpected_bec54635-fb82-4f28-8b84-d0be16084180" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_028a7448-f6e4-467b-85b2-dff33e8771fa" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_6096400f-5456-44a7-a9df-e1570950351b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_6096400f-5456-44a7-a9df-e1570950351b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSecurities_61279b95-4db2-4e86-ade1-81bbaba44d32" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSecurities_61279b95-4db2-4e86-ade1-81bbaba44d32" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalentsAndSecurities_7ff9b9cc-d18a-4f87-a051-76c01bcc09a9" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalentsAndSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalentsAndSecurities_7ff9b9cc-d18a-4f87-a051-76c01bcc09a9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsMarketableSecurities_d0a6635b-29c0-47e3-abfd-60ed26548b1d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsMarketableSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsMarketableSecurities_d0a6635b-29c0-47e3-abfd-60ed26548b1d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherInvestments_87728212-f1aa-488a-b7a5-58026896403f" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherInvestments_87728212-f1aa-488a-b7a5-58026896403f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivable_fecdbdff-9733-49ae-923d-d656ed2be376" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivable_fecdbdff-9733-49ae-923d-d656ed2be376" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFederalReserveBankStock_34ddaca8-b97c-4646-8fd2-ba27951306fc" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFederalReserveBankStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFederalReserveBankStock_34ddaca8-b97c-4646-8fd2-ba27951306fc" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFederalHomeLoanBankStock_6af49a59-a438-488c-adf3-8ca1a6216fbc" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFederalHomeLoanBankStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFederalHomeLoanBankStock_6af49a59-a438-488c-adf3-8ca1a6216fbc" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedInterestReceivable_00027ba8-c8f8-411c-afe4-1944e95b7ce1" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedInterestReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedInterestReceivable_00027ba8-c8f8-411c-afe4-1944e95b7ce1" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets_412bec6a-cf10-4b71-b8fc-6750666668fc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets_412bec6a-cf10-4b71-b8fc-6750666668fc" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_98123d5b-727a-4f60-98fd-6ef641597233" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_us-gaap_Goodwill_98123d5b-727a-4f60-98fd-6ef641597233" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_a9cf65d8-b3b6-4958-bccc-eade78674928" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_a9cf65d8-b3b6-4958-bccc-eade78674928" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAssets_c5ba30d6-e420-4ba3-8aa7-f75e20a394a9" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAssets_c5ba30d6-e420-4ba3-8aa7-f75e20a394a9" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_33ca4d30-f3b5-466f-97d1-d1a932b9e45b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_b966f732-9adc-4cb2-a56a-35929c08f5e6" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_33ca4d30-f3b5-466f-97d1-d1a932b9e45b" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_9b523fb9-b156-419f-895c-1b2b3cda5386" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_028a7448-f6e4-467b-85b2-dff33e8771fa" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_9b523fb9-b156-419f-895c-1b2b3cda5386" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsByTypeAbstract_7fe52d89-01df-4754-9ef5-492c0f91ab5f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepositsByTypeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_9b523fb9-b156-419f-895c-1b2b3cda5386" xlink:to="loc_us-gaap_DepositsByTypeAbstract_7fe52d89-01df-4754-9ef5-492c0f91ab5f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoninterestBearingDepositLiabilities_91774b31-bafe-4f2c-a653-428d86ac4763" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoninterestBearingDepositLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DepositsByTypeAbstract_7fe52d89-01df-4754-9ef5-492c0f91ab5f" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoninterestBearingDepositLiabilities_91774b31-bafe-4f2c-a653-428d86ac4763" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInterestBearingDomesticDepositMoneyMarket_61d5853e-92ab-42a5-ae61-1e7eec5f0497" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInterestBearingDomesticDepositMoneyMarket"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DepositsByTypeAbstract_7fe52d89-01df-4754-9ef5-492c0f91ab5f" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInterestBearingDomesticDepositMoneyMarket_61d5853e-92ab-42a5-ae61-1e7eec5f0497" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCertificatesOfDeposit_eb84449e-da55-4b90-93a4-35c8f49cc559" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCertificatesOfDeposit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DepositsByTypeAbstract_7fe52d89-01df-4754-9ef5-492c0f91ab5f" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCertificatesOfDeposit_eb84449e-da55-4b90-93a4-35c8f49cc559" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeposits_be19a2e5-0721-4636-9c9a-6505a94393ac" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DepositsByTypeAbstract_7fe52d89-01df-4754-9ef5-492c0f91ab5f" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeposits_be19a2e5-0721-4636-9c9a-6505a94393ac" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAdvanceFromFederalHomeLoanBank_616b4388-7fcd-4cdb-bc67-e03cd64b1eda" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAdvanceFromFederalHomeLoanBank"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_9b523fb9-b156-419f-895c-1b2b3cda5386" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAdvanceFromFederalHomeLoanBank_616b4388-7fcd-4cdb-bc67-e03cd64b1eda" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccountsPayableAndOtherAccruedLiabilities_8606b462-ec0b-4a8c-a48b-c7f600fac16c" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccountsPayableAndOtherAccruedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_9b523fb9-b156-419f-895c-1b2b3cda5386" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccountsPayableAndOtherAccruedLiabilities_8606b462-ec0b-4a8c-a48b-c7f600fac16c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_5a3deeae-30a7-453c-8eee-df9c5651ec99" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_9b523fb9-b156-419f-895c-1b2b3cda5386" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_5a3deeae-30a7-453c-8eee-df9c5651ec99" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BUSINESSCOMBINATIONSLoansPurchasedDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BUSINESSCOMBINATIONSLoansPurchasedDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BUSINESSCOMBINATIONSLoansPurchasedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_1964f9da-3e87-43f5-a6d9-7e94cfe391bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_cd2bdfab-59d0-4ee9-b508-28c400804199" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1964f9da-3e87-43f5-a6d9-7e94cfe391bc" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_cd2bdfab-59d0-4ee9-b508-28c400804199" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_80fc403f-1fd5-46b5-a299-59ddef5665d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_cd2bdfab-59d0-4ee9-b508-28c400804199" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_80fc403f-1fd5-46b5-a299-59ddef5665d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_80fc403f-1fd5-46b5-a299-59ddef5665d6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_80fc403f-1fd5-46b5-a299-59ddef5665d6" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_80fc403f-1fd5-46b5-a299-59ddef5665d6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_a31911ac-fd43-496f-975c-9049a6ef81f3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_80fc403f-1fd5-46b5-a299-59ddef5665d6" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_a31911ac-fd43-496f-975c-9049a6ef81f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NationalBankOfNewYorkCityMember_9c39d478-1671-49fc-a2d8-5b8f84ece906" xlink:href="newt-20241231.xsd#newt_NationalBankOfNewYorkCityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_a31911ac-fd43-496f-975c-9049a6ef81f3" xlink:to="loc_newt_NationalBankOfNewYorkCityMember_9c39d478-1671-49fc-a2d8-5b8f84ece906" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusAxis_6679dfd9-e346-4490-9757-84dd8533a18c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditLossStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_cd2bdfab-59d0-4ee9-b508-28c400804199" xlink:to="loc_us-gaap_CreditLossStatusAxis_6679dfd9-e346-4490-9757-84dd8533a18c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusDomain_6679dfd9-e346-4490-9757-84dd8533a18c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditLossStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditLossStatusAxis_6679dfd9-e346-4490-9757-84dd8533a18c" xlink:to="loc_us-gaap_CreditLossStatusDomain_6679dfd9-e346-4490-9757-84dd8533a18c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusDomain_96ccbb2a-da37-4707-805d-0c8a779f1c12" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditLossStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditLossStatusAxis_6679dfd9-e346-4490-9757-84dd8533a18c" xlink:to="loc_us-gaap_CreditLossStatusDomain_96ccbb2a-da37-4707-805d-0c8a779f1c12" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember_79a05d1b-cb67-444d-a2ff-345555759a7c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditLossStatusDomain_96ccbb2a-da37-4707-805d-0c8a779f1c12" xlink:to="loc_us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember_79a05d1b-cb67-444d-a2ff-345555759a7c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivable_c358adb5-d3bb-4391-801b-d61564dbda49" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1964f9da-3e87-43f5-a6d9-7e94cfe391bc" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivable_c358adb5-d3bb-4391-801b-d61564dbda49" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivableAllowanceForCreditLoss_26cbea2e-eb76-4735-b9aa-1fe9c17da4d9" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivableAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1964f9da-3e87-43f5-a6d9-7e94cfe391bc" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivableAllowanceForCreditLoss_26cbea2e-eb76-4735-b9aa-1fe9c17da4d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivableCreditDiscount_76096912-2915-452a-949a-ea595a0d9ffc" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivableCreditDiscount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1964f9da-3e87-43f5-a6d9-7e94cfe391bc" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivableCreditDiscount_76096912-2915-452a-949a-ea595a0d9ffc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivableFairValue_e8c637f8-8f2a-4971-ac11-2f8e78d79b1c" xlink:href="newt-20241231.xsd#newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivableFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1964f9da-3e87-43f5-a6d9-7e94cfe391bc" xlink:to="loc_newt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancingReceivableFairValue_e8c637f8-8f2a-4971-ac11-2f8e78d79b1c" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/INVESTMENTSInvestmentPortfolioDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#INVESTMENTSInvestmentPortfolioDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/INVESTMENTSInvestmentPortfolioDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_4b487e77-8021-44e3-a08b-d7ee761aa75b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_45866acc-6987-4a15-9c25-c51274f8404a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_4b487e77-8021-44e3-a08b-d7ee761aa75b" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_45866acc-6987-4a15-9c25-c51274f8404a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_9f1c5af5-dac3-4e67-a250-6b6a995fd5e7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_45866acc-6987-4a15-9c25-c51274f8404a" xlink:to="loc_us-gaap_InvestmentTypeAxis_9f1c5af5-dac3-4e67-a250-6b6a995fd5e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_9f1c5af5-dac3-4e67-a250-6b6a995fd5e7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_9f1c5af5-dac3-4e67-a250-6b6a995fd5e7" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_9f1c5af5-dac3-4e67-a250-6b6a995fd5e7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_392eee90-eff3-4313-9a1f-63fda8eb853b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_9f1c5af5-dac3-4e67-a250-6b6a995fd5e7" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_392eee90-eff3-4313-9a1f-63fda8eb853b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtSecuritiesAvailableForSaleMember_31a758c5-b58f-4ba5-87af-cd1cc589f675" xlink:href="newt-20241231.xsd#newt_DebtSecuritiesAvailableForSaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_392eee90-eff3-4313-9a1f-63fda8eb853b" xlink:to="loc_newt_DebtSecuritiesAvailableForSaleMember_31a758c5-b58f-4ba5-87af-cd1cc589f675" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FederalHomeLoanBankAndFederalReserveBankStockMember_9e680901-aea1-4512-8771-b28a369d637d" xlink:href="newt-20241231.xsd#newt_FederalHomeLoanBankAndFederalReserveBankStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_392eee90-eff3-4313-9a1f-63fda8eb853b" xlink:to="loc_newt_FederalHomeLoanBankAndFederalReserveBankStockMember_9e680901-aea1-4512-8771-b28a369d637d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_TotalInvestmentsMember_44e5ddf5-006f-469d-a2b3-ccccdafda17e" xlink:href="newt-20241231.xsd#newt_TotalInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_392eee90-eff3-4313-9a1f-63fda8eb853b" xlink:to="loc_newt_TotalInvestmentsMember_44e5ddf5-006f-469d-a2b3-ccccdafda17e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_d64fd168-4521-4621-b06d-4e3c8faf2022" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_45866acc-6987-4a15-9c25-c51274f8404a" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_d64fd168-4521-4621-b06d-4e3c8faf2022" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_d64fd168-4521-4621-b06d-4e3c8faf2022_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_d64fd168-4521-4621-b06d-4e3c8faf2022" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_d64fd168-4521-4621-b06d-4e3c8faf2022_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_f5f98c71-ee14-4e1d-a978-4b1526e5ecdc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_d64fd168-4521-4621-b06d-4e3c8faf2022" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_f5f98c71-ee14-4e1d-a978-4b1526e5ecdc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember_21ae0ea0-ceec-4bd0-97fe-8a093f1e6f9f" xlink:href="newt-20241231.xsd#newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_f5f98c71-ee14-4e1d-a978-4b1526e5ecdc" xlink:to="loc_newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember_21ae0ea0-ceec-4bd0-97fe-8a093f1e6f9f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_db712db9-b51d-4198-ba14-96b70adacc06" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_4b487e77-8021-44e3-a08b-d7ee761aa75b" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_db712db9-b51d-4198-ba14-96b70adacc06" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_295509a4-57a3-4829-b335-ee38d9909c4c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_4b487e77-8021-44e3-a08b-d7ee761aa75b" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_295509a4-57a3-4829-b335-ee38d9909c4c" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/INVESTMENTSNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#INVESTMENTSNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/INVESTMENTSNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9ab9a388-c89d-40fb-a412-4c7b8ca3c193" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_cdcaa27c-9b6a-4989-a335-7e53b08e4fea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9ab9a388-c89d-40fb-a412-4c7b8ca3c193" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_cdcaa27c-9b6a-4989-a335-7e53b08e4fea" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_e459e405-c26d-45e5-a41a-f5820fd26797" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_cdcaa27c-9b6a-4989-a335-7e53b08e4fea" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_e459e405-c26d-45e5-a41a-f5820fd26797" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_e459e405-c26d-45e5-a41a-f5820fd26797_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_e459e405-c26d-45e5-a41a-f5820fd26797" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_e459e405-c26d-45e5-a41a-f5820fd26797_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_ba79b38b-3a6d-423b-8a7b-c84ff317a7e6" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_e459e405-c26d-45e5-a41a-f5820fd26797" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_ba79b38b-3a6d-423b-8a7b-c84ff317a7e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NewtekConventionalLendingLLCMember_fce56ea3-350e-4017-a6f2-672367f3c9be" xlink:href="newt-20241231.xsd#newt_NewtekConventionalLendingLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_ba79b38b-3a6d-423b-8a7b-c84ff317a7e6" xlink:to="loc_newt_NewtekConventionalLendingLLCMember_fce56ea3-350e-4017-a6f2-672367f3c9be" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_4bc738df-c7a0-43b6-aa78-bde1d07d6667" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_cdcaa27c-9b6a-4989-a335-7e53b08e4fea" xlink:to="loc_dei_LegalEntityAxis_4bc738df-c7a0-43b6-aa78-bde1d07d6667" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_4bc738df-c7a0-43b6-aa78-bde1d07d6667_default" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_4bc738df-c7a0-43b6-aa78-bde1d07d6667" xlink:to="loc_dei_EntityDomain_4bc738df-c7a0-43b6-aa78-bde1d07d6667_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_34ada62e-9135-49b8-9554-8b50fd6526cc" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_4bc738df-c7a0-43b6-aa78-bde1d07d6667" xlink:to="loc_dei_EntityDomain_34ada62e-9135-49b8-9554-8b50fd6526cc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NewtekCommercialLendingMember_ca5f234e-c6dd-4d42-bf84-c88bc31d0a08" xlink:href="newt-20241231.xsd#newt_NewtekCommercialLendingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_34ada62e-9135-49b8-9554-8b50fd6526cc" xlink:to="loc_newt_NewtekCommercialLendingMember_ca5f234e-c6dd-4d42-bf84-c88bc31d0a08" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ConventionalLendingTCPHoldingMember_816ef286-5c5c-49fb-a2fa-a7046117f5e3" xlink:href="newt-20241231.xsd#newt_ConventionalLendingTCPHoldingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_34ada62e-9135-49b8-9554-8b50fd6526cc" xlink:to="loc_newt_ConventionalLendingTCPHoldingMember_816ef286-5c5c-49fb-a2fa-a7046117f5e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_49552318-1ac5-444f-8331-6abfeac524f5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_cdcaa27c-9b6a-4989-a335-7e53b08e4fea" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_49552318-1ac5-444f-8331-6abfeac524f5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_49552318-1ac5-444f-8331-6abfeac524f5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_49552318-1ac5-444f-8331-6abfeac524f5" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_49552318-1ac5-444f-8331-6abfeac524f5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_3ff4da9b-2f25-4421-8308-369a1a9843cd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_49552318-1ac5-444f-8331-6abfeac524f5" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_3ff4da9b-2f25-4421-8308-369a1a9843cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NewtekConventionalLendingLLCMember_9e39f700-4b97-4466-a23c-0893792538d3" xlink:href="newt-20241231.xsd#newt_NewtekConventionalLendingLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_3ff4da9b-2f25-4421-8308-369a1a9843cd" xlink:to="loc_newt_NewtekConventionalLendingLLCMember_9e39f700-4b97-4466-a23c-0893792538d3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_abde2633-1ddd-44bb-860e-d37b7d92abec" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_cdcaa27c-9b6a-4989-a335-7e53b08e4fea" xlink:to="loc_us-gaap_DebtInstrumentAxis_abde2633-1ddd-44bb-860e-d37b7d92abec" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_abde2633-1ddd-44bb-860e-d37b7d92abec_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_abde2633-1ddd-44bb-860e-d37b7d92abec" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_abde2633-1ddd-44bb-860e-d37b7d92abec_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_21375fb1-3b2e-4ff8-8b99-33d59978e37f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_abde2633-1ddd-44bb-860e-d37b7d92abec" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_21375fb1-3b2e-4ff8-8b99-33d59978e37f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_TSONotesClassANotesMember_7afadc58-a78c-4f50-9181-1dd309295611" xlink:href="newt-20241231.xsd#newt_TSONotesClassANotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_21375fb1-3b2e-4ff8-8b99-33d59978e37f" xlink:to="loc_newt_TSONotesClassANotesMember_7afadc58-a78c-4f50-9181-1dd309295611" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_TSONotesClassBNotesMember_4e7371b0-2c34-4407-ba6f-6595bba184bd" xlink:href="newt-20241231.xsd#newt_TSONotesClassBNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_21375fb1-3b2e-4ff8-8b99-33d59978e37f" xlink:to="loc_newt_TSONotesClassBNotesMember_4e7371b0-2c34-4407-ba6f-6595bba184bd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_TSONotesMember_3c2c5cc3-aa89-4823-9e68-431b55eaae38" xlink:href="newt-20241231.xsd#newt_TSONotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_21375fb1-3b2e-4ff8-8b99-33d59978e37f" xlink:to="loc_newt_TSONotesMember_3c2c5cc3-aa89-4823-9e68-431b55eaae38" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_d7b191b3-5dd3-470f-9782-2ab19e93d8fb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9ab9a388-c89d-40fb-a412-4c7b8ca3c193" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_d7b191b3-5dd3-470f-9782-2ab19e93d8fb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InvestmentOwnedSales_8f8f2d10-5ec0-4d5f-9587-f1b3f89e6b4e" xlink:href="newt-20241231.xsd#newt_InvestmentOwnedSales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9ab9a388-c89d-40fb-a412-4c7b8ca3c193" xlink:to="loc_newt_InvestmentOwnedSales_8f8f2d10-5ec0-4d5f-9587-f1b3f89e6b4e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InvestmentOwnedSalesYield_3d1f395c-dffb-4073-b240-7d5d509a337b" xlink:href="newt-20241231.xsd#newt_InvestmentOwnedSalesYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9ab9a388-c89d-40fb-a412-4c7b8ca3c193" xlink:to="loc_newt_InvestmentOwnedSalesYield_3d1f395c-dffb-4073-b240-7d5d509a337b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NotesSoldValue_80d94ed6-236e-41e7-81b0-0b55df257e28" xlink:href="newt-20241231.xsd#newt_NotesSoldValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9ab9a388-c89d-40fb-a412-4c7b8ca3c193" xlink:to="loc_newt_NotesSoldValue_80d94ed6-236e-41e7-81b0-0b55df257e28" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCollateralAmount_a3c27764-e98c-4380-9f5d-9b16afc80d99" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentCollateralAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9ab9a388-c89d-40fb-a412-4c7b8ca3c193" xlink:to="loc_us-gaap_DebtInstrumentCollateralAmount_a3c27764-e98c-4380-9f5d-9b16afc80d99" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss_727ad34c-9a39-4ba9-b76a-9bbae0f2ffe5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9ab9a388-c89d-40fb-a412-4c7b8ca3c193" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss_727ad34c-9a39-4ba9-b76a-9bbae0f2ffe5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList_e72452ce-0fa5-4fde-84e4-e622724bb058" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9ab9a388-c89d-40fb-a412-4c7b8ca3c193" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList_e72452ce-0fa5-4fde-84e4-e622724bb058" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/INVESTMENTSJointVentureSummarizedFinancialInformationDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#INVESTMENTSJointVentureSummarizedFinancialInformationDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/INVESTMENTSJointVentureSummarizedFinancialInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_ee3cc0c3-6625-4e6c-9446-1bf1e4fc612c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_dd64dbe6-3101-4839-81d2-8df2a1ed654d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_ee3cc0c3-6625-4e6c-9446-1bf1e4fc612c" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_dd64dbe6-3101-4839-81d2-8df2a1ed654d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_20424540-a84a-4dd0-8c13-0693f3c157a6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_dd64dbe6-3101-4839-81d2-8df2a1ed654d" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_20424540-a84a-4dd0-8c13-0693f3c157a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_20424540-a84a-4dd0-8c13-0693f3c157a6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_20424540-a84a-4dd0-8c13-0693f3c157a6" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_20424540-a84a-4dd0-8c13-0693f3c157a6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_563471e3-9c0d-4647-a1b1-23012609e6f4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_20424540-a84a-4dd0-8c13-0693f3c157a6" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_563471e3-9c0d-4647-a1b1-23012609e6f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NewtekConventionalLendingLLCMember_354d5533-410b-4b92-ab32-bc22bf46f515" xlink:href="newt-20241231.xsd#newt_NewtekConventionalLendingLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_563471e3-9c0d-4647-a1b1-23012609e6f4" xlink:to="loc_newt_NewtekConventionalLendingLLCMember_354d5533-410b-4b92-ab32-bc22bf46f515" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NewtekTSOIIConventionalCreditPartnersLPMember_cd9f0482-43c9-4a74-940b-ef8713d59686" xlink:href="newt-20241231.xsd#newt_NewtekTSOIIConventionalCreditPartnersLPMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_563471e3-9c0d-4647-a1b1-23012609e6f4" xlink:to="loc_newt_NewtekTSOIIConventionalCreditPartnersLPMember_cd9f0482-43c9-4a74-940b-ef8713d59686" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentCompanyBalanceSheetItemsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_ee3cc0c3-6625-4e6c-9446-1bf1e4fc612c" xlink:to="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Cash_b61b209b-1f33-409c-b1e8-80cb4b4eaf74" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Cash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_Cash_b61b209b-1f33-409c-b1e8-80cb4b4eaf74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCash_a56de0bb-f183-419c-9e6c-49f8fc7b0a79" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_RestrictedCash_a56de0bb-f183-419c-9e6c-49f8fc7b0a79" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_c017f86b-4223-4194-8218-84729e2f0159" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_c017f86b-4223-4194-8218-84729e2f0159" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_3d021ea9-8e08-4e2f-ab72-9a2f969c474c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_3d021ea9-8e08-4e2f-ab72-9a2f969c474c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssets_be5b23b2-3ba1-4985-8365-f9cf337ba7e5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_OtherAssets_be5b23b2-3ba1-4985-8365-f9cf337ba7e5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_91cde920-eb70-42ef-be82-690c0acfd8af" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_Assets_91cde920-eb70-42ef-be82-690c0acfd8af" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesPayableToBank_bcc6026c-3a1b-4ca0-ad40-1ab9134754ba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NotesPayableToBank"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_NotesPayableToBank_bcc6026c-3a1b-4ca0-ad40-1ab9134754ba" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebt_9187fc7b-192f-48c7-a8ee-dab41ef0c146" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuredDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_SecuredDebt_9187fc7b-192f-48c7-a8ee-dab41ef0c146" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilities_7465d00b-2cf2-4068-934a-7a275e49556e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_OtherLiabilities_7465d00b-2cf2-4068-934a-7a275e49556e" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_7333b75f-9462-49c1-8719-63e8c53a5d4e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_Liabilities_7333b75f-9462-49c1-8719-63e8c53a5d4e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_b2040d47-e78b-43ed-b148-9f22a457b816" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_StockholdersEquity_b2040d47-e78b-43ed-b148-9f22a457b816" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_4a93b69f-e54a-45fb-876c-4ceaa0d3a983" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyBalanceSheetItemsAbstract_1e828327-711f-413e-9695-cc17a0f1434f" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_4a93b69f-e54a-45fb-876c-4ceaa0d3a983" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyIncomeAndExpenseAbstract_38f4c940-8608-447d-b1a1-9746503b690f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentCompanyIncomeAndExpenseAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_ee3cc0c3-6625-4e6c-9446-1bf1e4fc612c" xlink:to="loc_us-gaap_InvestmentCompanyIncomeAndExpenseAbstract_38f4c940-8608-447d-b1a1-9746503b690f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndOtherIncome_3c82c0a5-53cc-47e2-9dce-b8ef526c1a22" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestAndOtherIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyIncomeAndExpenseAbstract_38f4c940-8608-447d-b1a1-9746503b690f" xlink:to="loc_us-gaap_InterestAndOtherIncome_3c82c0a5-53cc-47e2-9dce-b8ef526c1a22" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInvestmentExpense_b3ce36aa-ce0a-4eac-88ad-29252dac0d85" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIncomeInvestmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyIncomeAndExpenseAbstract_38f4c940-8608-447d-b1a1-9746503b690f" xlink:to="loc_us-gaap_InvestmentIncomeInvestmentExpense_b3ce36aa-ce0a-4eac-88ad-29252dac0d85" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetInvestmentIncome_df676c27-9996-4db8-9f53-93c9a358fbff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetInvestmentIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyIncomeAndExpenseAbstract_38f4c940-8608-447d-b1a1-9746503b690f" xlink:to="loc_us-gaap_NetInvestmentIncome_df676c27-9996-4db8-9f53-93c9a358fbff" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss_b93fd5de-5fc0-4a05-988d-1d4a228211ba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyIncomeAndExpenseAbstract_38f4c940-8608-447d-b1a1-9746503b690f" xlink:to="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss_b93fd5de-5fc0-4a05-988d-1d4a228211ba" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealizedInvestmentGainsLosses_85c8e403-ac65-439e-9b9f-f3c12c8e53eb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RealizedInvestmentGainsLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyIncomeAndExpenseAbstract_38f4c940-8608-447d-b1a1-9746503b690f" xlink:to="loc_us-gaap_RealizedInvestmentGainsLosses_85c8e403-ac65-439e-9b9f-f3c12c8e53eb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfDerivatives_2e739ae7-790f-4e8a-a457-30298309bbbe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainLossOnSaleOfDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyIncomeAndExpenseAbstract_38f4c940-8608-447d-b1a1-9746503b690f" xlink:to="loc_us-gaap_GainLossOnSaleOfDerivatives_2e739ae7-790f-4e8a-a457-30298309bbbe" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_816f5fe6-1181-44b9-87e8-02288872ca0b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyIncomeAndExpenseAbstract_38f4c940-8608-447d-b1a1-9746503b690f" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_816f5fe6-1181-44b9-87e8-02288872ca0b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_46a50e33-0c2d-487e-9b3f-b2abfe5446d3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyIncomeAndExpenseAbstract_38f4c940-8608-447d-b1a1-9746503b690f" xlink:to="loc_us-gaap_NetIncomeLoss_46a50e33-0c2d-487e-9b3f-b2abfe5446d3" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/INVESTMENTSTransactionwithAffiliatedCompaniesDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#INVESTMENTSTransactionwithAffiliatedCompaniesDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/INVESTMENTSTransactionwithAffiliatedCompaniesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_0ae380e3-93dd-42d4-9055-51d06adb3882" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_c942cf80-3408-478b-8c51-befa144069af" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_0ae380e3-93dd-42d4-9055-51d06adb3882" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_c942cf80-3408-478b-8c51-befa144069af" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIdentifierAxis_065b9728-ccf6-45ad-a5b5-8b50ec172dcd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_c942cf80-3408-478b-8c51-befa144069af" xlink:to="loc_us-gaap_InvestmentIdentifierAxis_065b9728-ccf6-45ad-a5b5-8b50ec172dcd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_767a02a0-16ea-4396-a365-d0070f20d581" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_c942cf80-3408-478b-8c51-befa144069af" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_767a02a0-16ea-4396-a365-d0070f20d581" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_767a02a0-16ea-4396-a365-d0070f20d581_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_767a02a0-16ea-4396-a365-d0070f20d581" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_767a02a0-16ea-4396-a365-d0070f20d581_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_115884a3-cb63-44f6-931b-0b4fc6e243d5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_767a02a0-16ea-4396-a365-d0070f20d581" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_115884a3-cb63-44f6-931b-0b4fc6e243d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerMember_d24d2799-fd78-48e6-9098-1733b09121b9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentAffiliatedIssuerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_115884a3-cb63-44f6-931b-0b4fc6e243d5" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerMember_d24d2799-fd78-48e6-9098-1733b09121b9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherControlledCompaniesMember_76084d50-8369-497b-95f1-8d3058748353" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherControlledCompaniesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentAffiliatedIssuerMember_d24d2799-fd78-48e6-9098-1733b09121b9" xlink:to="loc_us-gaap_OtherControlledCompaniesMember_76084d50-8369-497b-95f1-8d3058748353" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_ec399a34-6ffd-4dc3-a54c-fc0972e5acd8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentAffiliatedIssuerMember_d24d2799-fd78-48e6-9098-1733b09121b9" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_ec399a34-6ffd-4dc3-a54c-fc0972e5acd8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:href="newt-20241231.xsd#newt_InvestmentOwnedFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_0ae380e3-93dd-42d4-9055-51d06adb3882" xlink:to="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_1b70df6a-f53b-4efb-b0d6-4adef5845a23" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_1b70df6a-f53b-4efb-b0d6-4adef5845a23" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity_ca7939fb-cb1f-4f97-8aff-75e4079ca7fd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:to="loc_us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity_ca7939fb-cb1f-4f97-8aff-75e4079ca7fd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ReturnOfInvestmentOperatingActivity_3da871ae-0179-4858-b511-e43517aa3a8b" xlink:href="newt-20241231.xsd#newt_ReturnOfInvestmentOperatingActivity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:to="loc_newt_ReturnOfInvestmentOperatingActivity_3da871ae-0179-4858-b511-e43517aa3a8b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss_555702c3-09b8-43a3-8ef5-83ad746c76b5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:to="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss_555702c3-09b8-43a3-8ef5-83ad746c76b5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_97cca2c7-0c98-4eaa-ad29-0148b6fdf92a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_0281b1f5-b83d-445d-9b11-e3166aac0af0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_0ae380e3-93dd-42d4-9055-51d06adb3882" xlink:to="loc_us-gaap_DividendIncomeOperating_0281b1f5-b83d-445d-9b11-e3166aac0af0" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/INVESTMENTSTransactionwithAffiliatedCompaniesDetails_1" xlink:type="simple" xlink:href="newt-20241231.xsd#INVESTMENTSTransactionwithAffiliatedCompaniesDetails_1"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/INVESTMENTSTransactionwithAffiliatedCompaniesDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_0ae380e3-93dd-42d4-9055-51d06adb3882" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_c942cf80-3408-478b-8c51-befa144069af" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_0ae380e3-93dd-42d4-9055-51d06adb3882" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_c942cf80-3408-478b-8c51-befa144069af" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_767a02a0-16ea-4396-a365-d0070f20d581" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_c942cf80-3408-478b-8c51-befa144069af" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_767a02a0-16ea-4396-a365-d0070f20d581" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_767a02a0-16ea-4396-a365-d0070f20d581_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_767a02a0-16ea-4396-a365-d0070f20d581" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_767a02a0-16ea-4396-a365-d0070f20d581_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_115884a3-cb63-44f6-931b-0b4fc6e243d5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_767a02a0-16ea-4396-a365-d0070f20d581" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_115884a3-cb63-44f6-931b-0b4fc6e243d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerMember_d24d2799-fd78-48e6-9098-1733b09121b9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentAffiliatedIssuerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_115884a3-cb63-44f6-931b-0b4fc6e243d5" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerMember_d24d2799-fd78-48e6-9098-1733b09121b9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherControlledCompaniesMember_76084d50-8369-497b-95f1-8d3058748353" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherControlledCompaniesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentAffiliatedIssuerMember_d24d2799-fd78-48e6-9098-1733b09121b9" xlink:to="loc_us-gaap_OtherControlledCompaniesMember_76084d50-8369-497b-95f1-8d3058748353" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_ec399a34-6ffd-4dc3-a54c-fc0972e5acd8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentAffiliatedIssuerMember_d24d2799-fd78-48e6-9098-1733b09121b9" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_ec399a34-6ffd-4dc3-a54c-fc0972e5acd8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:href="newt-20241231.xsd#newt_InvestmentOwnedFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_0ae380e3-93dd-42d4-9055-51d06adb3882" xlink:to="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_1b70df6a-f53b-4efb-b0d6-4adef5845a23" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_1b70df6a-f53b-4efb-b0d6-4adef5845a23" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity_ca7939fb-cb1f-4f97-8aff-75e4079ca7fd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:to="loc_us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity_ca7939fb-cb1f-4f97-8aff-75e4079ca7fd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ReturnOfInvestmentOperatingActivity_3da871ae-0179-4858-b511-e43517aa3a8b" xlink:href="newt-20241231.xsd#newt_ReturnOfInvestmentOperatingActivity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:to="loc_newt_ReturnOfInvestmentOperatingActivity_3da871ae-0179-4858-b511-e43517aa3a8b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss_555702c3-09b8-43a3-8ef5-83ad746c76b5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_InvestmentOwnedFairValueRollForward_4e4987ad-af9c-4016-beae-c776439359ae" xlink:to="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss_555702c3-09b8-43a3-8ef5-83ad746c76b5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_97cca2c7-0c98-4eaa-ad29-0148b6fdf92a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_0281b1f5-b83d-445d-9b11-e3166aac0af0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_0ae380e3-93dd-42d4-9055-51d06adb3882" xlink:to="loc_us-gaap_DividendIncomeOperating_0281b1f5-b83d-445d-9b11-e3166aac0af0" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/INVESTMENTSAvailableforSaleDebtSecuritiesDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#INVESTMENTSAvailableforSaleDebtSecuritiesDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/INVESTMENTSAvailableforSaleDebtSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9db46f25-929f-431a-9cab-963dc81acc06" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_3a309961-08f1-48ef-b6c2-0a610e3bfd64" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9db46f25-929f-431a-9cab-963dc81acc06" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_3a309961-08f1-48ef-b6c2-0a610e3bfd64" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_e155b0be-007e-43dd-83b6-f61925c683f3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_3a309961-08f1-48ef-b6c2-0a610e3bfd64" xlink:to="loc_us-gaap_FinancialInstrumentAxis_e155b0be-007e-43dd-83b6-f61925c683f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_e155b0be-007e-43dd-83b6-f61925c683f3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_e155b0be-007e-43dd-83b6-f61925c683f3" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_e155b0be-007e-43dd-83b6-f61925c683f3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_98287c46-5159-4bd5-a0ed-864c26c2f0d4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_e155b0be-007e-43dd-83b6-f61925c683f3" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_98287c46-5159-4bd5-a0ed-864c26c2f0d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_77f05d8e-11ec-4954-9577-623dd10421e0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_98287c46-5159-4bd5-a0ed-864c26c2f0d4" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_77f05d8e-11ec-4954-9577-623dd10421e0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_d79175ef-d170-469a-ab00-1a28ba7a3a89" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_98287c46-5159-4bd5-a0ed-864c26c2f0d4" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_d79175ef-d170-469a-ab00-1a28ba7a3a89" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PledgedForDepositsMember_cf67a6f6-1e5e-40fd-973b-fa94634ae504" xlink:href="newt-20241231.xsd#newt_PledgedForDepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_98287c46-5159-4bd5-a0ed-864c26c2f0d4" xlink:to="loc_newt_PledgedForDepositsMember_cf67a6f6-1e5e-40fd-973b-fa94634ae504" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PledgedForBorrowingsMember_61492db5-5c9f-4b02-8edd-50e0fd212aa4" xlink:href="newt-20241231.xsd#newt_PledgedForBorrowingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_98287c46-5159-4bd5-a0ed-864c26c2f0d4" xlink:to="loc_newt_PledgedForBorrowingsMember_61492db5-5c9f-4b02-8edd-50e0fd212aa4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_de43f0f6-53de-4aa2-8039-bddbb4f9cbdc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9db46f25-929f-431a-9cab-963dc81acc06" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_de43f0f6-53de-4aa2-8039-bddbb4f9cbdc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_565b34d3-fd59-4c70-b8de-d2b2a98ef202" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_de43f0f6-53de-4aa2-8039-bddbb4f9cbdc" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_565b34d3-fd59-4c70-b8de-d2b2a98ef202" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_25466ff6-ce49-4f6b-9270-c57fb0cd76a7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_de43f0f6-53de-4aa2-8039-bddbb4f9cbdc" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_25466ff6-ce49-4f6b-9270-c57fb0cd76a7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_1306f67f-ea34-492e-97ca-dd41395ef054" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_de43f0f6-53de-4aa2-8039-bddbb4f9cbdc" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_1306f67f-ea34-492e-97ca-dd41395ef054" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_03b2b2f4-a7e8-49b2-a90c-6ca71529760c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_de43f0f6-53de-4aa2-8039-bddbb4f9cbdc" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_03b2b2f4-a7e8-49b2-a90c-6ca71529760c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PledgedFinancialInstrumentsNotSeparatelyReportedDebtSecuritiesAvailableForSale_29e6e1dd-f1d0-43f8-9416-a073cb18199c" xlink:href="newt-20241231.xsd#newt_PledgedFinancialInstrumentsNotSeparatelyReportedDebtSecuritiesAvailableForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_9db46f25-929f-431a-9cab-963dc81acc06" xlink:to="loc_newt_PledgedFinancialInstrumentsNotSeparatelyReportedDebtSecuritiesAvailableForSale_29e6e1dd-f1d0-43f8-9416-a073cb18199c" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/INVESTMENTSDebtSecuritiesUnrealizedLossesDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#INVESTMENTSDebtSecuritiesUnrealizedLossesDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/INVESTMENTSDebtSecuritiesUnrealizedLossesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7d01c478-9bcc-4258-8394-bb1ae07906b3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_8f27fc18-44a0-4ac0-a664-f22aa65b59f8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7d01c478-9bcc-4258-8394-bb1ae07906b3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_8f27fc18-44a0-4ac0-a664-f22aa65b59f8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_48364619-aef8-4024-ae48-5287345d86a0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_8f27fc18-44a0-4ac0-a664-f22aa65b59f8" xlink:to="loc_us-gaap_FinancialInstrumentAxis_48364619-aef8-4024-ae48-5287345d86a0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_48364619-aef8-4024-ae48-5287345d86a0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_48364619-aef8-4024-ae48-5287345d86a0" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_48364619-aef8-4024-ae48-5287345d86a0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7b562b3b-65e0-4658-aca9-4bd002c7703b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_48364619-aef8-4024-ae48-5287345d86a0" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7b562b3b-65e0-4658-aca9-4bd002c7703b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_1e53e7a0-4cfe-4be4-8354-58d45212964e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7b562b3b-65e0-4658-aca9-4bd002c7703b" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_1e53e7a0-4cfe-4be4-8354-58d45212964e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_2002cc69-8183-4e65-88cf-d75c95a449ef" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7b562b3b-65e0-4658-aca9-4bd002c7703b" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_2002cc69-8183-4e65-88cf-d75c95a449ef" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_4c544002-d960-44d5-b1c0-9e397b068571" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7d01c478-9bcc-4258-8394-bb1ae07906b3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_4c544002-d960-44d5-b1c0-9e397b068571" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_bcfe1f0d-df19-429c-81af-1c14f7ffe8e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7d01c478-9bcc-4258-8394-bb1ae07906b3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_bcfe1f0d-df19-429c-81af-1c14f7ffe8e2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_40fc409c-2f06-46ff-9a85-0fee5b1347d7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7d01c478-9bcc-4258-8394-bb1ae07906b3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_40fc409c-2f06-46ff-9a85-0fee5b1347d7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_361b87e5-8029-4710-835c-7919b4758d85" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7d01c478-9bcc-4258-8394-bb1ae07906b3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_361b87e5-8029-4710-835c-7919b4758d85" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions_392f5182-a884-4f40-87f2-979f6d985767" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7d01c478-9bcc-4258-8394-bb1ae07906b3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions_392f5182-a884-4f40-87f2-979f6d985767" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_6cc2c707-6c4f-49a7-8a32-51eb5034ba7f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7d01c478-9bcc-4258-8394-bb1ae07906b3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_6cc2c707-6c4f-49a7-8a32-51eb5034ba7f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_8da345c8-eff3-4c51-bea1-5457993c1d4a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7d01c478-9bcc-4258-8394-bb1ae07906b3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_8da345c8-eff3-4c51-bea1-5457993c1d4a" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/LOANSInvestmentPortfolioDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#LOANSInvestmentPortfolioDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/LOANSInvestmentPortfolioDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_ffb3692e-17d0-468e-883f-f689cb8cb9a0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_54dc96f5-ceeb-4dba-926e-8af1d07c00ca" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_ffb3692e-17d0-468e-883f-f689cb8cb9a0" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_54dc96f5-ceeb-4dba-926e-8af1d07c00ca" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralAxis_3131660f-710d-4410-bb9d-acca12c662e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CollateralAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_54dc96f5-ceeb-4dba-926e-8af1d07c00ca" xlink:to="loc_us-gaap_CollateralAxis_3131660f-710d-4410-bb9d-acca12c662e2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralDomain_3131660f-710d-4410-bb9d-acca12c662e2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CollateralDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CollateralAxis_3131660f-710d-4410-bb9d-acca12c662e2" xlink:to="loc_us-gaap_CollateralDomain_3131660f-710d-4410-bb9d-acca12c662e2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralDomain_146c3d46-bcd7-4ffd-be26-ef4f6a10d721" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CollateralDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CollateralAxis_3131660f-710d-4410-bb9d-acca12c662e2" xlink:to="loc_us-gaap_CollateralDomain_146c3d46-bcd7-4ffd-be26-ef4f6a10d721" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CRECollateralMember_86d63279-40e4-4f4f-af16-3b023d42aa92" xlink:href="newt-20241231.xsd#newt_CRECollateralMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_146c3d46-bcd7-4ffd-be26-ef4f6a10d721" xlink:to="loc_newt_CRECollateralMember_86d63279-40e4-4f4f-af16-3b023d42aa92" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ResidentialRealEstateCollateralMember_e595f89a-a657-4b2c-b0e9-31afd5efa40e" xlink:href="newt-20241231.xsd#newt_ResidentialRealEstateCollateralMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_146c3d46-bcd7-4ffd-be26-ef4f6a10d721" xlink:to="loc_newt_ResidentialRealEstateCollateralMember_e595f89a-a657-4b2c-b0e9-31afd5efa40e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_MachineryAndEquipmentCollateralMember_fdbb8258-6fe0-4a3f-9939-50efa6019226" xlink:href="newt-20241231.xsd#newt_MachineryAndEquipmentCollateralMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_146c3d46-bcd7-4ffd-be26-ef4f6a10d721" xlink:to="loc_newt_MachineryAndEquipmentCollateralMember_fdbb8258-6fe0-4a3f-9939-50efa6019226" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_AccountsReceivableAndInventoryCollateralMember_e8ff01d0-27bb-4343-8033-222418ee6dd5" xlink:href="newt-20241231.xsd#newt_AccountsReceivableAndInventoryCollateralMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_146c3d46-bcd7-4ffd-be26-ef4f6a10d721" xlink:to="loc_newt_AccountsReceivableAndInventoryCollateralMember_e8ff01d0-27bb-4343-8033-222418ee6dd5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_UnsecuredCollateralMember_03b747a4-9e69-4afd-82fa-307e2cb299a8" xlink:href="newt-20241231.xsd#newt_UnsecuredCollateralMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_146c3d46-bcd7-4ffd-be26-ef4f6a10d721" xlink:to="loc_newt_UnsecuredCollateralMember_03b747a4-9e69-4afd-82fa-307e2cb299a8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_AllOtherIndustriesMember_e73c84d6-e18e-46a5-8980-6b74a20d6f66" xlink:href="newt-20241231.xsd#newt_AllOtherIndustriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_146c3d46-bcd7-4ffd-be26-ef4f6a10d721" xlink:to="loc_newt_AllOtherIndustriesMember_e73c84d6-e18e-46a5-8980-6b74a20d6f66" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_5a2887c2-3f64-49dc-970d-95b975a9dba7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_54dc96f5-ceeb-4dba-926e-8af1d07c00ca" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_5a2887c2-3f64-49dc-970d-95b975a9dba7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_5a2887c2-3f64-49dc-970d-95b975a9dba7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_5a2887c2-3f64-49dc-970d-95b975a9dba7" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_5a2887c2-3f64-49dc-970d-95b975a9dba7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_d70a5c05-f471-49dd-9630-92e5c38f2f13" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_5a2887c2-3f64-49dc-970d-95b975a9dba7" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_d70a5c05-f471-49dd-9630-92e5c38f2f13" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanMember_bc55ea65-26bb-432f-b689-bb124f0bf69a" xlink:href="newt-20241231.xsd#newt_SBA7aLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_d70a5c05-f471-49dd-9630-92e5c38f2f13" xlink:to="loc_newt_SBA7aLoanMember_bc55ea65-26bb-432f-b689-bb124f0bf69a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralAxis_9206eecf-500d-487f-be8c-6cb1d3417212" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CollateralAxis"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralDomain_9206eecf-500d-487f-be8c-6cb1d3417212_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CollateralDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralDomain_74146c67-691d-4bcf-b736-7d361b1e5e85" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CollateralDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossAmortizedCostIndustryLoans_fbed7b96-6a02-4efc-87c3-d4ba5d0cf945" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossAmortizedCostIndustryLoans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_ffb3692e-17d0-468e-883f-f689cb8cb9a0" xlink:to="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossAmortizedCostIndustryLoans_fbed7b96-6a02-4efc-87c3-d4ba5d0cf945" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueIndustryLoans_991b2329-9f0a-4125-be84-93f71a2f0e69" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueIndustryLoans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_ffb3692e-17d0-468e-883f-f689cb8cb9a0" xlink:to="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueIndustryLoans_991b2329-9f0a-4125-be84-93f71a2f0e69" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/LOANSLoansDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#LOANSLoansDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/LOANSLoansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_80bdcc6d-d65a-429e-800b-f3bb7de2c3b4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_d1921ae2-5d55-4eb6-93ee-b6043eb9dcb6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_80bdcc6d-d65a-429e-800b-f3bb7de2c3b4" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_d1921ae2-5d55-4eb6-93ee-b6043eb9dcb6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_47db4392-a06c-4ac9-aada-a80c31d35125" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_d1921ae2-5d55-4eb6-93ee-b6043eb9dcb6" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_47db4392-a06c-4ac9-aada-a80c31d35125" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_47db4392-a06c-4ac9-aada-a80c31d35125_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_47db4392-a06c-4ac9-aada-a80c31d35125" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_47db4392-a06c-4ac9-aada-a80c31d35125_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_52ceed5e-f126-4171-997d-d491b9e33c9b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_47db4392-a06c-4ac9-aada-a80c31d35125" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_52ceed5e-f126-4171-997d-d491b9e33c9b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanMember_e942d9af-8871-4dca-a26d-8a1aa5afe6be" xlink:href="newt-20241231.xsd#newt_SBA7aLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_52ceed5e-f126-4171-997d-d491b9e33c9b" xlink:to="loc_newt_SBA7aLoanMember_e942d9af-8871-4dca-a26d-8a1aa5afe6be" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstateMember_7bc0cdb6-e115-404e-8505-5957d8ed3d32" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialRealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_52ceed5e-f126-4171-997d-d491b9e33c9b" xlink:to="loc_us-gaap_CommercialRealEstateMember_7bc0cdb6-e115-404e-8505-5957d8ed3d32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommercialAndIndustrialLoansMember_4a9d5958-60d1-4ff4-aac2-b485f6e01100" xlink:href="newt-20241231.xsd#newt_CommercialAndIndustrialLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_52ceed5e-f126-4171-997d-d491b9e33c9b" xlink:to="loc_newt_CommercialAndIndustrialLoansMember_4a9d5958-60d1-4ff4-aac2-b485f6e01100" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansMember_1e3f501e-d088-47f8-9019-bd5704880e65" xlink:href="newt-20241231.xsd#newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_52ceed5e-f126-4171-997d-d491b9e33c9b" xlink:to="loc_newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansMember_1e3f501e-d088-47f8-9019-bd5704880e65" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_ed028822-c72a-4803-ab80-f60dbbcf5cad" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_80bdcc6d-d65a-429e-800b-f3bb7de2c3b4" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_ed028822-c72a-4803-ab80-f60dbbcf5cad" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossDeferredLoanFees_eb2a446f-16da-4c25-a6a7-e180e120809c" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossDeferredLoanFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_80bdcc6d-d65a-429e-800b-f3bb7de2c3b4" xlink:to="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossDeferredLoanFees_eb2a446f-16da-4c25-a6a7-e180e120809c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossAfterDeferredLoanFees_9103eea7-ec7d-4f4b-8f04-d929200e4001" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossAfterDeferredLoanFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_80bdcc6d-d65a-429e-800b-f3bb7de2c3b4" xlink:to="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossAfterDeferredLoanFees_9103eea7-ec7d-4f4b-8f04-d929200e4001" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/LOANSAgingStatusDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#LOANSAgingStatusDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/LOANSAgingStatusDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_6bbc352d-6ee8-48a8-a0e2-1d83d8d546bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_5de6da97-df1d-410b-a292-4265a48f7d94" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_6bbc352d-6ee8-48a8-a0e2-1d83d8d546bc" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_5de6da97-df1d-410b-a292-4265a48f7d94" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentPerformanceStatusAxis_68130c04-2d48-43b9-9671-ef6f5c2374a8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentPerformanceStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_5de6da97-df1d-410b-a292-4265a48f7d94" xlink:to="loc_us-gaap_FinancialInstrumentPerformanceStatusAxis_68130c04-2d48-43b9-9671-ef6f5c2374a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_68130c04-2d48-43b9-9671-ef6f5c2374a8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentPerformanceStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentPerformanceStatusAxis_68130c04-2d48-43b9-9671-ef6f5c2374a8" xlink:to="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_68130c04-2d48-43b9-9671-ef6f5c2374a8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_b2b1fa57-4af4-4315-a510-7036c3e60805" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentPerformanceStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentPerformanceStatusAxis_68130c04-2d48-43b9-9671-ef6f5c2374a8" xlink:to="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_b2b1fa57-4af4-4315-a510-7036c3e60805" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformingFinancingReceivableMember_c54d7340-9ac4-434d-a9be-bca9a8fd58e4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PerformingFinancingReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_b2b1fa57-4af4-4315-a510-7036c3e60805" xlink:to="loc_us-gaap_PerformingFinancingReceivableMember_c54d7340-9ac4-434d-a9be-bca9a8fd58e4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonperformingFinancingReceivableMember_c99379f9-5724-45f3-8382-90884d447ab5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NonperformingFinancingReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_b2b1fa57-4af4-4315-a510-7036c3e60805" xlink:to="loc_us-gaap_NonperformingFinancingReceivableMember_c99379f9-5724-45f3-8382-90884d447ab5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_e4688a76-18f1-42d0-a4e1-1dc1a61c89fc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_5de6da97-df1d-410b-a292-4265a48f7d94" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_e4688a76-18f1-42d0-a4e1-1dc1a61c89fc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_e4688a76-18f1-42d0-a4e1-1dc1a61c89fc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_e4688a76-18f1-42d0-a4e1-1dc1a61c89fc" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_e4688a76-18f1-42d0-a4e1-1dc1a61c89fc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_f5712c44-20a1-416c-8849-14039838263d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_e4688a76-18f1-42d0-a4e1-1dc1a61c89fc" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_f5712c44-20a1-416c-8849-14039838263d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember_920e1abc-73c7-458d-bada-96c8aad69262" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivables30To59DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_f5712c44-20a1-416c-8849-14039838263d" xlink:to="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember_920e1abc-73c7-458d-bada-96c8aad69262" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables60To89DaysPastDueMember_746f29df-2f5e-4494-a771-25f5f486f256" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivables60To89DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_f5712c44-20a1-416c-8849-14039838263d" xlink:to="loc_us-gaap_FinancingReceivables60To89DaysPastDueMember_746f29df-2f5e-4494-a771-25f5f486f256" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancialAsset90To119DaysPastDueMember_991820ec-eda9-4652-a80b-074df82cba18" xlink:href="newt-20241231.xsd#newt_FinancialAsset90To119DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_f5712c44-20a1-416c-8849-14039838263d" xlink:to="loc_newt_FinancialAsset90To119DaysPastDueMember_991820ec-eda9-4652-a80b-074df82cba18" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancialAssetEqualToOrGreaterThan120DaysPastDueMember_a89f7c97-cf63-465c-9e54-c05bcae5cb04" xlink:href="newt-20241231.xsd#newt_FinancialAssetEqualToOrGreaterThan120DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_f5712c44-20a1-416c-8849-14039838263d" xlink:to="loc_newt_FinancialAssetEqualToOrGreaterThan120DaysPastDueMember_a89f7c97-cf63-465c-9e54-c05bcae5cb04" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetPastDueMember_47046872-3f42-499d-ad86-dc4051cc57ca" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialAssetPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_f5712c44-20a1-416c-8849-14039838263d" xlink:to="loc_us-gaap_FinancialAssetPastDueMember_47046872-3f42-499d-ad86-dc4051cc57ca" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetNotPastDueMember_750cbf23-3eb4-4c2a-8281-e740623bd110" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialAssetNotPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_f5712c44-20a1-416c-8849-14039838263d" xlink:to="loc_us-gaap_FinancialAssetNotPastDueMember_750cbf23-3eb4-4c2a-8281-e740623bd110" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_9c1d3645-9b90-4049-9704-9e3b71d4e394" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_5de6da97-df1d-410b-a292-4265a48f7d94" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_9c1d3645-9b90-4049-9704-9e3b71d4e394" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_9c1d3645-9b90-4049-9704-9e3b71d4e394_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_9c1d3645-9b90-4049-9704-9e3b71d4e394" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_9c1d3645-9b90-4049-9704-9e3b71d4e394_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_caa42643-070e-41cd-836a-9966c0f90b6b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_9c1d3645-9b90-4049-9704-9e3b71d4e394" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_caa42643-070e-41cd-836a-9966c0f90b6b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanLowerOfCostOrMarketMember_1dbe250d-abd7-479f-b71d-a2b4f7e2defe" xlink:href="newt-20241231.xsd#newt_SBA7aLoanLowerOfCostOrMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_caa42643-070e-41cd-836a-9966c0f90b6b" xlink:to="loc_newt_SBA7aLoanLowerOfCostOrMarketMember_1dbe250d-abd7-479f-b71d-a2b4f7e2defe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstateMember_543ecf40-7c4e-4f71-aa42-eff8fb366867" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialRealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_caa42643-070e-41cd-836a-9966c0f90b6b" xlink:to="loc_us-gaap_CommercialRealEstateMember_543ecf40-7c4e-4f71-aa42-eff8fb366867" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommercialAndIndustrialLoansMember_9764bd84-0437-4696-ac82-4fc2bc353b73" xlink:href="newt-20241231.xsd#newt_CommercialAndIndustrialLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_caa42643-070e-41cd-836a-9966c0f90b6b" xlink:to="loc_newt_CommercialAndIndustrialLoansMember_9764bd84-0437-4696-ac82-4fc2bc353b73" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansMember_17b68682-e3c0-4b2e-807b-3d53f467df82" xlink:href="newt-20241231.xsd#newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_caa42643-070e-41cd-836a-9966c0f90b6b" xlink:to="loc_newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansMember_17b68682-e3c0-4b2e-807b-3d53f467df82" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure_d73f394b-1232-4896-a838-0a7ed167f50c" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_6bbc352d-6ee8-48a8-a0e2-1d83d8d546bc" xlink:to="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure_d73f394b-1232-4896-a838-0a7ed167f50c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_fb5c0d0d-2d17-49a4-8c71-b19c16304980" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_6bbc352d-6ee8-48a8-a0e2-1d83d8d546bc" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_fb5c0d0d-2d17-49a4-8c71-b19c16304980" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual_c2823e50-ecfc-4bd0-b510-fa2f95630696" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_6bbc352d-6ee8-48a8-a0e2-1d83d8d546bc" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual_c2823e50-ecfc-4bd0-b510-fa2f95630696" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossDeferredLoanFees_ec0f830e-a714-44e0-8cee-56e138bff6b2" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossDeferredLoanFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_6bbc352d-6ee8-48a8-a0e2-1d83d8d546bc" xlink:to="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossDeferredLoanFees_ec0f830e-a714-44e0-8cee-56e138bff6b2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_aa4d07e1-c32f-4d7b-bb8f-f48d6cb7278c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_6bbc352d-6ee8-48a8-a0e2-1d83d8d546bc" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_aa4d07e1-c32f-4d7b-bb8f-f48d6cb7278c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_6e82da3c-85e9-4b68-b9b2-4e8e7e6f967b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_6bbc352d-6ee8-48a8-a0e2-1d83d8d546bc" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_6e82da3c-85e9-4b68-b9b2-4e8e7e6f967b" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/LOANSCreditQualityIndicatorsDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#LOANSCreditQualityIndicatorsDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/LOANSCreditQualityIndicatorsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a85583e7-cabd-4e41-922b-c0df874dc1fd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_be26ad03-00ed-431b-b556-3bdd6095d179" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a85583e7-cabd-4e41-922b-c0df874dc1fd" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_be26ad03-00ed-431b-b556-3bdd6095d179" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_d6d1356c-c534-4356-acec-fa1b76c68d13" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_be26ad03-00ed-431b-b556-3bdd6095d179" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_d6d1356c-c534-4356-acec-fa1b76c68d13" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_d6d1356c-c534-4356-acec-fa1b76c68d13_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_d6d1356c-c534-4356-acec-fa1b76c68d13" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_d6d1356c-c534-4356-acec-fa1b76c68d13_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_e42246c1-8992-494f-b77e-90a36ea3f320" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_d6d1356c-c534-4356-acec-fa1b76c68d13" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_e42246c1-8992-494f-b77e-90a36ea3f320" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanMember_b29dd8f6-8860-453c-b0da-cafb44ead816" xlink:href="newt-20241231.xsd#newt_SBA7aLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_e42246c1-8992-494f-b77e-90a36ea3f320" xlink:to="loc_newt_SBA7aLoanMember_b29dd8f6-8860-453c-b0da-cafb44ead816" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanLowerOfCostOrMarketMember_f6121eeb-166c-460a-8c2a-5d7da5d46556" xlink:href="newt-20241231.xsd#newt_SBA7aLoanLowerOfCostOrMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_e42246c1-8992-494f-b77e-90a36ea3f320" xlink:to="loc_newt_SBA7aLoanLowerOfCostOrMarketMember_f6121eeb-166c-460a-8c2a-5d7da5d46556" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstateMember_30c275e4-aecb-40eb-bf00-cfe7d7a55b72" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialRealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_e42246c1-8992-494f-b77e-90a36ea3f320" xlink:to="loc_us-gaap_CommercialRealEstateMember_30c275e4-aecb-40eb-bf00-cfe7d7a55b72" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommercialAndIndustrialLoansMember_bbe31dea-59e8-4e18-a856-92e2815fef82" xlink:href="newt-20241231.xsd#newt_CommercialAndIndustrialLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_e42246c1-8992-494f-b77e-90a36ea3f320" xlink:to="loc_newt_CommercialAndIndustrialLoansMember_bbe31dea-59e8-4e18-a856-92e2815fef82" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansAtFairValueAndCostMember_a8ee0d42-ce6d-4874-ba7b-97d42b6c24b9" xlink:href="newt-20241231.xsd#newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansAtFairValueAndCostMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_e42246c1-8992-494f-b77e-90a36ea3f320" xlink:to="loc_newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansAtFairValueAndCostMember_a8ee0d42-ce6d-4874-ba7b-97d42b6c24b9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentAxis_2e9d388a-6904-43f9-b8fc-aa94eb05a56c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InternalCreditAssessmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_be26ad03-00ed-431b-b556-3bdd6095d179" xlink:to="loc_us-gaap_InternalCreditAssessmentAxis_2e9d388a-6904-43f9-b8fc-aa94eb05a56c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_2e9d388a-6904-43f9-b8fc-aa94eb05a56c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_2e9d388a-6904-43f9-b8fc-aa94eb05a56c" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_2e9d388a-6904-43f9-b8fc-aa94eb05a56c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_a3fd6b5b-8579-493d-9d3c-3fb5b99cc2df" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_2e9d388a-6904-43f9-b8fc-aa94eb05a56c" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_a3fd6b5b-8579-493d-9d3c-3fb5b99cc2df" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_RiskGrades14Member_02e12f42-1103-468c-8c3a-f9de2990480b" xlink:href="newt-20241231.xsd#newt_RiskGrades14Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_a3fd6b5b-8579-493d-9d3c-3fb5b99cc2df" xlink:to="loc_newt_RiskGrades14Member_02e12f42-1103-468c-8c3a-f9de2990480b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_RiskGrades56Member_700a3998-0fc8-4961-8046-1b7cda9f075e" xlink:href="newt-20241231.xsd#newt_RiskGrades56Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_a3fd6b5b-8579-493d-9d3c-3fb5b99cc2df" xlink:to="loc_newt_RiskGrades56Member_700a3998-0fc8-4961-8046-1b7cda9f075e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_RiskGrade7Member_f2b1da1c-4f5c-4d88-b661-7f2d43127cc6" xlink:href="newt-20241231.xsd#newt_RiskGrade7Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_a3fd6b5b-8579-493d-9d3c-3fb5b99cc2df" xlink:to="loc_newt_RiskGrade7Member_f2b1da1c-4f5c-4d88-b661-7f2d43127cc6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_RiskGrade8Member_fc28426a-5040-4581-85ef-f9ced7a4ae90" xlink:href="newt-20241231.xsd#newt_RiskGrade8Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_a3fd6b5b-8579-493d-9d3c-3fb5b99cc2df" xlink:to="loc_newt_RiskGrade8Member_fc28426a-5040-4581-85ef-f9ced7a4ae90" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear_a4bdb998-f92b-45f2-b417-4b4ec7a13603" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a85583e7-cabd-4e41-922b-c0df874dc1fd" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear_a4bdb998-f92b-45f2-b417-4b4ec7a13603" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear_4e9a8698-3d7b-4576-bf2f-63574eae9f37" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a85583e7-cabd-4e41-922b-c0df874dc1fd" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear_4e9a8698-3d7b-4576-bf2f-63574eae9f37" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear_5fad4ad2-4cdc-4483-978e-bc07ca0c414f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a85583e7-cabd-4e41-922b-c0df874dc1fd" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear_5fad4ad2-4cdc-4483-978e-bc07ca0c414f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear_11a3e2f0-086a-4869-baf1-7f682a8abd76" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a85583e7-cabd-4e41-922b-c0df874dc1fd" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear_11a3e2f0-086a-4869-baf1-7f682a8abd76" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear_3e599fef-ac42-4853-b5bf-a61221f17144" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a85583e7-cabd-4e41-922b-c0df874dc1fd" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear_3e599fef-ac42-4853-b5bf-a61221f17144" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear_2f94c9b4-ad6a-4582-bffc-1abfdb6f4039" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a85583e7-cabd-4e41-922b-c0df874dc1fd" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear_2f94c9b4-ad6a-4582-bffc-1abfdb6f4039" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossAmortizedCostAndFairValue_4c0ad894-a503-4a32-ba5e-3b19d8151ea6" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossAmortizedCostAndFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a85583e7-cabd-4e41-922b-c0df874dc1fd" xlink:to="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossAmortizedCostAndFairValue_4c0ad894-a503-4a32-ba5e-3b19d8151ea6" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/LOANSAllowanceforCreditLossDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#LOANSAllowanceforCreditLossDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/LOANSAllowanceforCreditLossDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_9958aa94-7d32-460b-8252-e46c0321cde6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_c5264e56-66fd-4dd6-9ab1-870b2f3584b8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_9958aa94-7d32-460b-8252-e46c0321cde6" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_c5264e56-66fd-4dd6-9ab1-870b2f3584b8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_80721f0b-13f4-45f8-9a30-7a0ee0378435" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_c5264e56-66fd-4dd6-9ab1-870b2f3584b8" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_80721f0b-13f4-45f8-9a30-7a0ee0378435" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_80721f0b-13f4-45f8-9a30-7a0ee0378435_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_80721f0b-13f4-45f8-9a30-7a0ee0378435" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_80721f0b-13f4-45f8-9a30-7a0ee0378435_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_2fce4750-883f-4210-a904-73b417047df1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_80721f0b-13f4-45f8-9a30-7a0ee0378435" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_2fce4750-883f-4210-a904-73b417047df1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstateMember_cad02972-098d-43c5-b0d0-5541290ea240" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialRealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_2fce4750-883f-4210-a904-73b417047df1" xlink:to="loc_us-gaap_CommercialRealEstateMember_cad02972-098d-43c5-b0d0-5541290ea240" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommercialAndIndustrialLoansMember_fe201edf-b849-4aaa-8fbc-ff2471cc0bae" xlink:href="newt-20241231.xsd#newt_CommercialAndIndustrialLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_2fce4750-883f-4210-a904-73b417047df1" xlink:to="loc_newt_CommercialAndIndustrialLoansMember_fe201edf-b849-4aaa-8fbc-ff2471cc0bae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanMember_16e71d8d-a35c-4c1c-80b9-d245d2c27a43" xlink:href="newt-20241231.xsd#newt_SBA7aLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_2fce4750-883f-4210-a904-73b417047df1" xlink:to="loc_newt_SBA7aLoanMember_16e71d8d-a35c-4c1c-80b9-d245d2c27a43" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_74e67614-84e3-4546-8a56-b82298738430" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_9958aa94-7d32-460b-8252-e46c0321cde6" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_74e67614-84e3-4546-8a56-b82298738430" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_ff0c7aa5-e6f3-49d5-810f-059d81dc4810" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_74e67614-84e3-4546-8a56-b82298738430" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_ff0c7aa5-e6f3-49d5-810f-059d81dc4810" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableAllowanceForCreditLossAdjustedOpeningBalance_19c3aa71-823c-492c-b1d4-97121d05aa81" xlink:href="newt-20241231.xsd#newt_FinancingReceivableAllowanceForCreditLossAdjustedOpeningBalance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_74e67614-84e3-4546-8a56-b82298738430" xlink:to="loc_newt_FinancingReceivableAllowanceForCreditLossAdjustedOpeningBalance_19c3aa71-823c-492c-b1d4-97121d05aa81" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff_b7a0f4bd-16fe-449d-bd68-0d9f16e2d1b4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_74e67614-84e3-4546-8a56-b82298738430" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff_b7a0f4bd-16fe-449d-bd68-0d9f16e2d1b4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery_fea5229d-7fb5-4465-a8db-014d16c564c9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_74e67614-84e3-4546-8a56-b82298738430" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery_fea5229d-7fb5-4465-a8db-014d16c564c9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableCreditLossExpenseReversalExcludingUnfundedCommitments_e9b1f535-2017-4b12-86d3-a5cba4db83bc" xlink:href="newt-20241231.xsd#newt_FinancingReceivableCreditLossExpenseReversalExcludingUnfundedCommitments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_74e67614-84e3-4546-8a56-b82298738430" xlink:to="loc_newt_FinancingReceivableCreditLossExpenseReversalExcludingUnfundedCommitments_e9b1f535-2017-4b12-86d3-a5cba4db83bc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_8cbfc809-c16b-4a5e-9640-7151b0e3af15" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableCreditLossExpenseReversalUnfundedCommitments_214b7187-32b9-4dc9-bfac-59653927bf79" xlink:href="newt-20241231.xsd#newt_FinancingReceivableCreditLossExpenseReversalUnfundedCommitments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_9958aa94-7d32-460b-8252-e46c0321cde6" xlink:to="loc_newt_FinancingReceivableCreditLossExpenseReversalUnfundedCommitments_214b7187-32b9-4dc9-bfac-59653927bf79" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/LOANSIndividuallyandCollectivelyEvaluatedDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#LOANSIndividuallyandCollectivelyEvaluatedDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/LOANSIndividuallyandCollectivelyEvaluatedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_2fc6477e-92a1-4753-93ba-d39c88b1a817" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_bbd63714-01c3-4b76-aa3a-bc6add395f7c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_2fc6477e-92a1-4753-93ba-d39c88b1a817" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_bbd63714-01c3-4b76-aa3a-bc6add395f7c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_c04fe44b-9dac-4e06-b936-8669c9a2112f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_bbd63714-01c3-4b76-aa3a-bc6add395f7c" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_c04fe44b-9dac-4e06-b936-8669c9a2112f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_c04fe44b-9dac-4e06-b936-8669c9a2112f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_c04fe44b-9dac-4e06-b936-8669c9a2112f" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_c04fe44b-9dac-4e06-b936-8669c9a2112f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_5cdc2fa1-4cae-4e2d-92e2-7600ca9456b0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_c04fe44b-9dac-4e06-b936-8669c9a2112f" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_5cdc2fa1-4cae-4e2d-92e2-7600ca9456b0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstateMember_c4646104-18ed-4c9d-9c25-a5e5fcc88c31" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialRealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_5cdc2fa1-4cae-4e2d-92e2-7600ca9456b0" xlink:to="loc_us-gaap_CommercialRealEstateMember_c4646104-18ed-4c9d-9c25-a5e5fcc88c31" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommercialAndIndustrialLoansMember_ee7fd2f8-ec1e-4d4d-8f7d-eacafd8f4cee" xlink:href="newt-20241231.xsd#newt_CommercialAndIndustrialLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_5cdc2fa1-4cae-4e2d-92e2-7600ca9456b0" xlink:to="loc_newt_CommercialAndIndustrialLoansMember_ee7fd2f8-ec1e-4d4d-8f7d-eacafd8f4cee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanLowerOfCostOrMarketMember_41a67c88-dc9d-46c6-80f3-2304fc83c75a" xlink:href="newt-20241231.xsd#newt_SBA7aLoanLowerOfCostOrMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_5cdc2fa1-4cae-4e2d-92e2-7600ca9456b0" xlink:to="loc_newt_SBA7aLoanLowerOfCostOrMarketMember_41a67c88-dc9d-46c6-80f3-2304fc83c75a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansMember_dc566af8-ea03-438c-ab80-89474e96054a" xlink:href="newt-20241231.xsd#newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_5cdc2fa1-4cae-4e2d-92e2-7600ca9456b0" xlink:to="loc_newt_CommercialRealEstateCommercialIndustrialAndSBA7aLoansMember_dc566af8-ea03-438c-ab80-89474e96054a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossAdditionalInformationAbstract_c3050920-f420-4879-ad71-567a56b8f4ed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossAdditionalInformationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_2fc6477e-92a1-4753-93ba-d39c88b1a817" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossAdditionalInformationAbstract_c3050920-f420-4879-ad71-567a56b8f4ed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1_06312418-7f69-4ec1-92fc-14299cc678bb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossAdditionalInformationAbstract_c3050920-f420-4879-ad71-567a56b8f4ed" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1_06312418-7f69-4ec1-92fc-14299cc678bb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment_7691fab7-a67f-4c72-a9b5-ba2c28aa1727" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossAdditionalInformationAbstract_c3050920-f420-4879-ad71-567a56b8f4ed" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment_7691fab7-a67f-4c72-a9b5-ba2c28aa1727" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_92ddb040-2bf9-4b55-9d68-10c582116205" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossAdditionalInformationAbstract_c3050920-f420-4879-ad71-567a56b8f4ed" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_92ddb040-2bf9-4b55-9d68-10c582116205" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableNetAbstract_f01135f1-f54d-462a-b1cf-fa17e4b9e07b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NotesReceivableNetAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_2fc6477e-92a1-4753-93ba-d39c88b1a817" xlink:to="loc_us-gaap_NotesReceivableNetAbstract_f01135f1-f54d-462a-b1cf-fa17e4b9e07b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment_a9c99a31-74bb-42bf-890f-3aba503671f0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NotesReceivableNetAbstract_f01135f1-f54d-462a-b1cf-fa17e4b9e07b" xlink:to="loc_us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment_a9c99a31-74bb-42bf-890f-3aba503671f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment_9c02a900-a47c-48da-a285-8de3b9dd2b6a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NotesReceivableNetAbstract_f01135f1-f54d-462a-b1cf-fa17e4b9e07b" xlink:to="loc_us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment_9c02a900-a47c-48da-a285-8de3b9dd2b6a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossAmortizedCostAndFairValue_a76bf905-cee5-44e8-8252-954912bc55f6" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossAmortizedCostAndFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NotesReceivableNetAbstract_f01135f1-f54d-462a-b1cf-fa17e4b9e07b" xlink:to="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossAmortizedCostAndFairValue_a76bf905-cee5-44e8-8252-954912bc55f6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableNumberOfLoansIndividuallyEvaluated_8bd1c7e0-5676-4041-9c3c-7ff21359df8f" xlink:href="newt-20241231.xsd#newt_FinancingReceivableNumberOfLoansIndividuallyEvaluated"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_2fc6477e-92a1-4753-93ba-d39c88b1a817" xlink:to="loc_newt_FinancingReceivableNumberOfLoansIndividuallyEvaluated_8bd1c7e0-5676-4041-9c3c-7ff21359df8f" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/LOANSNonaccrualLoansDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#LOANSNonaccrualLoansDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/LOANSNonaccrualLoansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_63320c69-8205-48cf-b6d6-d0793280ce28" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_fd58808f-dbe7-437d-b325-023a8a07397e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_63320c69-8205-48cf-b6d6-d0793280ce28" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_fd58808f-dbe7-437d-b325-023a8a07397e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_554d26b0-d5c1-43e1-bd77-695d8fbeec40" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_fd58808f-dbe7-437d-b325-023a8a07397e" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_554d26b0-d5c1-43e1-bd77-695d8fbeec40" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_554d26b0-d5c1-43e1-bd77-695d8fbeec40_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_554d26b0-d5c1-43e1-bd77-695d8fbeec40" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_554d26b0-d5c1-43e1-bd77-695d8fbeec40_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_7508a5a5-27f3-4e91-918e-63121d23fbbf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_554d26b0-d5c1-43e1-bd77-695d8fbeec40" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_7508a5a5-27f3-4e91-918e-63121d23fbbf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanLowerOfCostOrMarketMember_d2bcef88-713a-4f77-8b8a-0f8a0c2fc0d5" xlink:href="newt-20241231.xsd#newt_SBA7aLoanLowerOfCostOrMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_7508a5a5-27f3-4e91-918e-63121d23fbbf" xlink:to="loc_newt_SBA7aLoanLowerOfCostOrMarketMember_d2bcef88-713a-4f77-8b8a-0f8a0c2fc0d5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstateMember_2352c767-15ce-4c33-b05a-2e926c3da3ab" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialRealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_7508a5a5-27f3-4e91-918e-63121d23fbbf" xlink:to="loc_us-gaap_CommercialRealEstateMember_2352c767-15ce-4c33-b05a-2e926c3da3ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance_642ee794-4bb7-4385-9729-e5dfe0d9230b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_63320c69-8205-48cf-b6d6-d0793280ce28" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance_642ee794-4bb7-4385-9729-e5dfe0d9230b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual_1c962a30-3f44-4ab3-ba86-a1184ec7ae01" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_63320c69-8205-48cf-b6d6-d0793280ce28" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual_1c962a30-3f44-4ab3-ba86-a1184ec7ae01" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableIndividuallyEvaluatedForCreditLossRelatedAllowance_191d7edf-2851-4b2a-8d4e-e4bc65b0069d" xlink:href="newt-20241231.xsd#newt_FinancingReceivableIndividuallyEvaluatedForCreditLossRelatedAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_63320c69-8205-48cf-b6d6-d0793280ce28" xlink:to="loc_newt_FinancingReceivableIndividuallyEvaluatedForCreditLossRelatedAllowance_191d7edf-2851-4b2a-8d4e-e4bc65b0069d" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/LOANSIndividuallyAssessedDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#LOANSIndividuallyAssessedDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/LOANSIndividuallyAssessedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a0fe25ec-05d3-4fc2-9bf3-9603fd29e119" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_08ed5e90-b4a0-44df-a51c-5420d47915e8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a0fe25ec-05d3-4fc2-9bf3-9603fd29e119" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_08ed5e90-b4a0-44df-a51c-5420d47915e8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralAxis_7446c00d-46d6-40ac-a34f-e616cfca3647" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CollateralAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_08ed5e90-b4a0-44df-a51c-5420d47915e8" xlink:to="loc_us-gaap_CollateralAxis_7446c00d-46d6-40ac-a34f-e616cfca3647" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralDomain_7446c00d-46d6-40ac-a34f-e616cfca3647_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CollateralDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CollateralAxis_7446c00d-46d6-40ac-a34f-e616cfca3647" xlink:to="loc_us-gaap_CollateralDomain_7446c00d-46d6-40ac-a34f-e616cfca3647_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralDomain_6112dce6-9a47-4f1d-b464-7a21f65ce9ac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CollateralDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CollateralAxis_7446c00d-46d6-40ac-a34f-e616cfca3647" xlink:to="loc_us-gaap_CollateralDomain_6112dce6-9a47-4f1d-b464-7a21f65ce9ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateMember_1ffd5edc-e469-4aef-ae66-9c9538ca4409" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_6112dce6-9a47-4f1d-b464-7a21f65ce9ac" xlink:to="loc_us-gaap_RealEstateMember_1ffd5edc-e469-4aef-ae66-9c9538ca4409" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UncollateralizedMember_2bbe1299-7ea8-4e83-96f9-7025053deae8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_UncollateralizedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_6112dce6-9a47-4f1d-b464-7a21f65ce9ac" xlink:to="loc_us-gaap_UncollateralizedMember_2bbe1299-7ea8-4e83-96f9-7025053deae8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_09c28856-6fa1-47fc-81be-cf6edaee2389" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_08ed5e90-b4a0-44df-a51c-5420d47915e8" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_09c28856-6fa1-47fc-81be-cf6edaee2389" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_09c28856-6fa1-47fc-81be-cf6edaee2389_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_09c28856-6fa1-47fc-81be-cf6edaee2389" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_09c28856-6fa1-47fc-81be-cf6edaee2389_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_591a14d7-d466-4db6-801a-773c5728f92e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_09c28856-6fa1-47fc-81be-cf6edaee2389" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_591a14d7-d466-4db6-801a-773c5728f92e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanLowerOfCostOrMarketMember_abed25cd-09c8-47a9-9550-d2f0f9bed43c" xlink:href="newt-20241231.xsd#newt_SBA7aLoanLowerOfCostOrMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_591a14d7-d466-4db6-801a-773c5728f92e" xlink:to="loc_newt_SBA7aLoanLowerOfCostOrMarketMember_abed25cd-09c8-47a9-9550-d2f0f9bed43c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstateMember_830cef1c-7281-4127-8fc4-fa556ec37f3f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialRealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_591a14d7-d466-4db6-801a-773c5728f92e" xlink:to="loc_us-gaap_CommercialRealEstateMember_830cef1c-7281-4127-8fc4-fa556ec37f3f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableIndividuallyEvaluatedForCreditLossUnpaidPrincipalBalance_78cfb85c-d1a2-4005-807f-5fe93c3182ef" xlink:href="newt-20241231.xsd#newt_FinancingReceivableIndividuallyEvaluatedForCreditLossUnpaidPrincipalBalance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a0fe25ec-05d3-4fc2-9bf3-9603fd29e119" xlink:to="loc_newt_FinancingReceivableIndividuallyEvaluatedForCreditLossUnpaidPrincipalBalance_78cfb85c-d1a2-4005-807f-5fe93c3182ef" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableIndividuallyEvaluatedForCreditLossRelatedAllowance_61398f55-be2c-4256-afd6-f1068adc5085" xlink:href="newt-20241231.xsd#newt_FinancingReceivableIndividuallyEvaluatedForCreditLossRelatedAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a0fe25ec-05d3-4fc2-9bf3-9603fd29e119" xlink:to="loc_newt_FinancingReceivableIndividuallyEvaluatedForCreditLossRelatedAllowance_61398f55-be2c-4256-afd6-f1068adc5085" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAccruedInterestBeforeAllowanceForCreditLoss_099f273f-d9dc-48ce-ab8b-b4556edcfe13" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_a0fe25ec-05d3-4fc2-9bf3-9603fd29e119" xlink:to="loc_us-gaap_FinancingReceivableAccruedInterestBeforeAllowanceForCreditLoss_099f273f-d9dc-48ce-ab8b-b4556edcfe13" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/LOANSAgingStatusofLoansDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#LOANSAgingStatusofLoansDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/LOANSAgingStatusofLoansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_9b44c798-fe96-46d5-8687-a7bdfc76462c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_d21549d3-d34e-41f0-8dca-c262139f270b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_9b44c798-fe96-46d5-8687-a7bdfc76462c" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_d21549d3-d34e-41f0-8dca-c262139f270b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentPerformanceStatusAxis_e43aec0b-ed79-4e14-ba05-07fd7584fe1f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentPerformanceStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_d21549d3-d34e-41f0-8dca-c262139f270b" xlink:to="loc_us-gaap_FinancialInstrumentPerformanceStatusAxis_e43aec0b-ed79-4e14-ba05-07fd7584fe1f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_e43aec0b-ed79-4e14-ba05-07fd7584fe1f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentPerformanceStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentPerformanceStatusAxis_e43aec0b-ed79-4e14-ba05-07fd7584fe1f" xlink:to="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_e43aec0b-ed79-4e14-ba05-07fd7584fe1f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_f219a683-153e-4004-9a79-1d9f80e19f95" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentPerformanceStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentPerformanceStatusAxis_e43aec0b-ed79-4e14-ba05-07fd7584fe1f" xlink:to="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_f219a683-153e-4004-9a79-1d9f80e19f95" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformingFinancingReceivableMember_dd5b32a0-69a2-4257-bbb2-ffa6eba97be3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PerformingFinancingReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_f219a683-153e-4004-9a79-1d9f80e19f95" xlink:to="loc_us-gaap_PerformingFinancingReceivableMember_dd5b32a0-69a2-4257-bbb2-ffa6eba97be3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonperformingFinancingReceivableMember_9da0e105-5e05-43e0-bd50-48f5c1a26d05" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NonperformingFinancingReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain_f219a683-153e-4004-9a79-1d9f80e19f95" xlink:to="loc_us-gaap_NonperformingFinancingReceivableMember_9da0e105-5e05-43e0-bd50-48f5c1a26d05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_e1f4b199-86b1-4c7a-927f-d2733c61e7c3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_d21549d3-d34e-41f0-8dca-c262139f270b" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_e1f4b199-86b1-4c7a-927f-d2733c61e7c3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_e1f4b199-86b1-4c7a-927f-d2733c61e7c3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_e1f4b199-86b1-4c7a-927f-d2733c61e7c3" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_e1f4b199-86b1-4c7a-927f-d2733c61e7c3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_22dbd5b1-73dd-4e70-a7e0-8efd9b39a1f5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_e1f4b199-86b1-4c7a-927f-d2733c61e7c3" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_22dbd5b1-73dd-4e70-a7e0-8efd9b39a1f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetPastDueMember_e295169e-48eb-41bf-8142-79c6d03562c6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialAssetPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_22dbd5b1-73dd-4e70-a7e0-8efd9b39a1f5" xlink:to="loc_us-gaap_FinancialAssetPastDueMember_e295169e-48eb-41bf-8142-79c6d03562c6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember_0c9f938f-7f18-4804-9ec0-2efee71e8316" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivables30To59DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_22dbd5b1-73dd-4e70-a7e0-8efd9b39a1f5" xlink:to="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember_0c9f938f-7f18-4804-9ec0-2efee71e8316" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables60To89DaysPastDueMember_ce2dc322-5f5b-42b8-8296-593d6cadc0ea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivables60To89DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_22dbd5b1-73dd-4e70-a7e0-8efd9b39a1f5" xlink:to="loc_us-gaap_FinancingReceivables60To89DaysPastDueMember_ce2dc322-5f5b-42b8-8296-593d6cadc0ea" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancialAsset90To119DaysPastDueMember_2337a23a-0702-4a18-a4f5-9bb27c91e506" xlink:href="newt-20241231.xsd#newt_FinancialAsset90To119DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_22dbd5b1-73dd-4e70-a7e0-8efd9b39a1f5" xlink:to="loc_newt_FinancialAsset90To119DaysPastDueMember_2337a23a-0702-4a18-a4f5-9bb27c91e506" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancialAssetEqualToOrGreaterThan120DaysPastDueMember_efcdb1b8-1ab0-43f2-bc85-e34f10b0a899" xlink:href="newt-20241231.xsd#newt_FinancialAssetEqualToOrGreaterThan120DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_22dbd5b1-73dd-4e70-a7e0-8efd9b39a1f5" xlink:to="loc_newt_FinancialAssetEqualToOrGreaterThan120DaysPastDueMember_efcdb1b8-1ab0-43f2-bc85-e34f10b0a899" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetNotPastDueMember_1afaa3ab-c61b-48e4-8121-6f5db2849356" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialAssetNotPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_22dbd5b1-73dd-4e70-a7e0-8efd9b39a1f5" xlink:to="loc_us-gaap_FinancialAssetNotPastDueMember_1afaa3ab-c61b-48e4-8121-6f5db2849356" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_0c330562-948b-4bb4-87b3-d54c9fd4c979" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_d21549d3-d34e-41f0-8dca-c262139f270b" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_0c330562-948b-4bb4-87b3-d54c9fd4c979" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_0c330562-948b-4bb4-87b3-d54c9fd4c979_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_0c330562-948b-4bb4-87b3-d54c9fd4c979" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_0c330562-948b-4bb4-87b3-d54c9fd4c979_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_badcd306-db94-4f59-b442-eb43f6ba20c1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_0c330562-948b-4bb4-87b3-d54c9fd4c979" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_badcd306-db94-4f59-b442-eb43f6ba20c1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanMember_192e3533-1b57-4a20-ba8e-f4f6d57d9810" xlink:href="newt-20241231.xsd#newt_SBA7aLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_badcd306-db94-4f59-b442-eb43f6ba20c1" xlink:to="loc_newt_SBA7aLoanMember_192e3533-1b57-4a20-ba8e-f4f6d57d9810" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ALPLoansMember_3140f1d8-9f24-45f4-9dad-a6e6132ef0ba" xlink:href="newt-20241231.xsd#newt_ALPLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_badcd306-db94-4f59-b442-eb43f6ba20c1" xlink:to="loc_newt_ALPLoansMember_3140f1d8-9f24-45f4-9dad-a6e6132ef0ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableHeldForSaleAmount_f79e7d55-8523-4c3e-a5b9-aed28f445487" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LoansReceivableHeldForSaleAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_9b44c798-fe96-46d5-8687-a7bdfc76462c" xlink:to="loc_us-gaap_LoansReceivableHeldForSaleAmount_f79e7d55-8523-4c3e-a5b9-aed28f445487" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableHeldForSaleLowerOfCostOrMarket_875de063-a3c1-4437-a663-20ce2fe40a85" xlink:href="newt-20241231.xsd#newt_FinancingReceivableHeldForSaleLowerOfCostOrMarket"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_9b44c798-fe96-46d5-8687-a7bdfc76462c" xlink:to="loc_newt_FinancingReceivableHeldForSaleLowerOfCostOrMarket_875de063-a3c1-4437-a663-20ce2fe40a85" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/LOANSHeldforSaleDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#LOANSHeldforSaleDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/LOANSHeldforSaleDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_f94d75d5-4c56-484d-ac14-1a2c28806b48" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_c537e776-583a-440b-840f-6a0231ae4e39" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_f94d75d5-4c56-484d-ac14-1a2c28806b48" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_c537e776-583a-440b-840f-6a0231ae4e39" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_106f0f63-ba66-4d6d-9e86-4b1b6d7f0a97" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_c537e776-583a-440b-840f-6a0231ae4e39" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_106f0f63-ba66-4d6d-9e86-4b1b6d7f0a97" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_106f0f63-ba66-4d6d-9e86-4b1b6d7f0a97_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_106f0f63-ba66-4d6d-9e86-4b1b6d7f0a97" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_106f0f63-ba66-4d6d-9e86-4b1b6d7f0a97_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_91b585cd-43f5-4a6b-8f0a-bca9ebccdf03" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_106f0f63-ba66-4d6d-9e86-4b1b6d7f0a97" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_91b585cd-43f5-4a6b-8f0a-bca9ebccdf03" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FirstLienMember_923e3909-f014-4ff9-a2ca-e7f7874f8783" xlink:href="newt-20241231.xsd#newt_FirstLienMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_91b585cd-43f5-4a6b-8f0a-bca9ebccdf03" xlink:to="loc_newt_FirstLienMember_923e3909-f014-4ff9-a2ca-e7f7874f8783" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SecondLienMember_40d0e5a8-ee95-40b8-8a7d-15fec724c92b" xlink:href="newt-20241231.xsd#newt_SecondLienMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_91b585cd-43f5-4a6b-8f0a-bca9ebccdf03" xlink:to="loc_newt_SecondLienMember_40d0e5a8-ee95-40b8-8a7d-15fec724c92b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanMember_a96eec8d-6ce7-4c41-863b-c24270409ef0" xlink:href="newt-20241231.xsd#newt_SBA7aLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_91b585cd-43f5-4a6b-8f0a-bca9ebccdf03" xlink:to="loc_newt_SBA7aLoanMember_a96eec8d-6ce7-4c41-863b-c24270409ef0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanPartialsMember_f0bcb95c-74c4-4e0a-a13c-cec9ec353e51" xlink:href="newt-20241231.xsd#newt_SBA7aLoanPartialsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_91b585cd-43f5-4a6b-8f0a-bca9ebccdf03" xlink:to="loc_newt_SBA7aLoanPartialsMember_f0bcb95c-74c4-4e0a-a13c-cec9ec353e51" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ALPLoansMember_769da769-95bb-4568-8871-75de02e509ea" xlink:href="newt-20241231.xsd#newt_ALPLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_91b585cd-43f5-4a6b-8f0a-bca9ebccdf03" xlink:to="loc_newt_ALPLoansMember_769da769-95bb-4568-8871-75de02e509ea" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableAtFairValueAbstract_c545ed93-0bbd-41ef-b164-156fe2877982" xlink:href="newt-20241231.xsd#newt_FinancingReceivableAtFairValueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_f94d75d5-4c56-484d-ac14-1a2c28806b48" xlink:to="loc_newt_FinancingReceivableAtFairValueAbstract_c545ed93-0bbd-41ef-b164-156fe2877982" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableHeldForSaleBeforeDeferredFeesAndCosts_5a224413-1ea9-4e6f-8488-f96082aa46b9" xlink:href="newt-20241231.xsd#newt_FinancingReceivableHeldForSaleBeforeDeferredFeesAndCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_FinancingReceivableAtFairValueAbstract_c545ed93-0bbd-41ef-b164-156fe2877982" xlink:to="loc_newt_FinancingReceivableHeldForSaleBeforeDeferredFeesAndCosts_5a224413-1ea9-4e6f-8488-f96082aa46b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableHeldForSaleAmount_3c219a76-76a4-4023-b23b-42f15170f903" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LoansReceivableHeldForSaleAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_FinancingReceivableAtFairValueAbstract_c545ed93-0bbd-41ef-b164-156fe2877982" xlink:to="loc_us-gaap_LoansReceivableHeldForSaleAmount_3c219a76-76a4-4023-b23b-42f15170f903" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableAtLowerOfCostOrMarketAbstract_8c869a97-6a91-4658-86ef-c198352177a6" xlink:href="newt-20241231.xsd#newt_FinancingReceivableAtLowerOfCostOrMarketAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_f94d75d5-4c56-484d-ac14-1a2c28806b48" xlink:to="loc_newt_FinancingReceivableAtLowerOfCostOrMarketAbstract_8c869a97-6a91-4658-86ef-c198352177a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableHeldForSaleLowerOfCostOrMarketBeforeDeferredFeesAndCosts_21b6c9d1-568c-45dd-8215-993594ff7ab0" xlink:href="newt-20241231.xsd#newt_FinancingReceivableHeldForSaleLowerOfCostOrMarketBeforeDeferredFeesAndCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_FinancingReceivableAtLowerOfCostOrMarketAbstract_8c869a97-6a91-4658-86ef-c198352177a6" xlink:to="loc_newt_FinancingReceivableHeldForSaleLowerOfCostOrMarketBeforeDeferredFeesAndCosts_21b6c9d1-568c-45dd-8215-993594ff7ab0" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSInvestmentswithAffiliatesDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSInvestmentswithAffiliatesDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSInvestmentswithAffiliatesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_b5423945-87b4-4241-a7c2-17ebbfb5d3c9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_56df6fd8-4681-428b-8eec-8a3e5229973d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_b5423945-87b4-4241-a7c2-17ebbfb5d3c9" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_56df6fd8-4681-428b-8eec-8a3e5229973d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_9cda8879-db25-48b7-a822-26879486ffee" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_56df6fd8-4681-428b-8eec-8a3e5229973d" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_9cda8879-db25-48b7-a822-26879486ffee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_9cda8879-db25-48b7-a822-26879486ffee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_9cda8879-db25-48b7-a822-26879486ffee" xlink:to="loc_us-gaap_RelatedPartyDomain_9cda8879-db25-48b7-a822-26879486ffee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_df6f99e3-aeaf-4336-8b45-a63afe58f910" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_9cda8879-db25-48b7-a822-26879486ffee" xlink:to="loc_us-gaap_RelatedPartyDomain_df6f99e3-aeaf-4336-8b45-a63afe58f910" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_f6dc321d-8c63-4480-8a19-5a16412272ce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_df6f99e3-aeaf-4336-8b45-a63afe58f910" xlink:to="loc_us-gaap_RelatedPartyMember_f6dc321d-8c63-4480-8a19-5a16412272ce" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_4e660523-a938-4998-9e55-6a08688e6ce3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_b5423945-87b4-4241-a7c2-17ebbfb5d3c9" xlink:to="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_4e660523-a938-4998-9e55-6a08688e6ce3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivables_e4b2979e-aac5-42f7-b205-10507a767d0e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_b5423945-87b4-4241-a7c2-17ebbfb5d3c9" xlink:to="loc_us-gaap_OtherReceivables_e4b2979e-aac5-42f7-b205-10507a767d0e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilities_1b63b2a5-69bd-4eb4-b984-8741ffda57e4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_b5423945-87b4-4241-a7c2-17ebbfb5d3c9" xlink:to="loc_us-gaap_OtherLiabilities_1b63b2a5-69bd-4eb4-b984-8741ffda57e4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_OtherReceivablesLiabilitiesNet_d7f41137-7848-4909-af8c-f9386d7f8146" xlink:href="newt-20241231.xsd#newt_OtherReceivablesLiabilitiesNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_b5423945-87b4-4241-a7c2-17ebbfb5d3c9" xlink:to="loc_newt_OtherReceivablesLiabilitiesNet_d7f41137-7848-4909-af8c-f9386d7f8146" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSTransactionswithJointVenturesDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSTransactionswithJointVenturesDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSTransactionswithJointVenturesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_1c7859d9-0d02-43f9-ac6f-2c95f64b6585" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_116167da-f536-4dd6-9aba-6686ca6b1dc6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_1c7859d9-0d02-43f9-ac6f-2c95f64b6585" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_116167da-f536-4dd6-9aba-6686ca6b1dc6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_77c969ff-d7bb-4f22-a08c-744502ee48fb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_116167da-f536-4dd6-9aba-6686ca6b1dc6" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_77c969ff-d7bb-4f22-a08c-744502ee48fb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_77c969ff-d7bb-4f22-a08c-744502ee48fb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_77c969ff-d7bb-4f22-a08c-744502ee48fb" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_77c969ff-d7bb-4f22-a08c-744502ee48fb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_08a82101-e5d2-4251-a189-0705441b0456" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_77c969ff-d7bb-4f22-a08c-744502ee48fb" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_08a82101-e5d2-4251-a189-0705441b0456" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherControlledCompaniesMember_f7d845ba-38ee-4023-ad14-2b990a25e09c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherControlledCompaniesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_08a82101-e5d2-4251-a189-0705441b0456" xlink:to="loc_us-gaap_OtherControlledCompaniesMember_f7d845ba-38ee-4023-ad14-2b990a25e09c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_500e4a1a-8a7d-4561-bcc4-11572073c8ef" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_116167da-f536-4dd6-9aba-6686ca6b1dc6" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_500e4a1a-8a7d-4561-bcc4-11572073c8ef" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_500e4a1a-8a7d-4561-bcc4-11572073c8ef_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_500e4a1a-8a7d-4561-bcc4-11572073c8ef" xlink:to="loc_us-gaap_RelatedPartyDomain_500e4a1a-8a7d-4561-bcc4-11572073c8ef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_787453e1-5e17-4db3-a276-cc3763cccebe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_500e4a1a-8a7d-4561-bcc4-11572073c8ef" xlink:to="loc_us-gaap_RelatedPartyDomain_787453e1-5e17-4db3-a276-cc3763cccebe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_b44a0889-6d33-4602-8e3d-62c89be99d30" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_787453e1-5e17-4db3-a276-cc3763cccebe" xlink:to="loc_us-gaap_RelatedPartyMember_b44a0889-6d33-4602-8e3d-62c89be99d30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets_b10f3f64-0e11-4140-8477-685433acb481" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_1c7859d9-0d02-43f9-ac6f-2c95f64b6585" xlink:to="loc_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets_b10f3f64-0e11-4140-8477-685433acb481" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeDividend_ba9ff630-b1e1-44a6-8185-4b10f83b53ca" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIncomeDividend"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_1c7859d9-0d02-43f9-ac6f-2c95f64b6585" xlink:to="loc_us-gaap_InvestmentIncomeDividend_ba9ff630-b1e1-44a6-8185-4b10f83b53ca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncome_aebe2f51-2ec4-46ab-88b9-3b04582629c2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_1c7859d9-0d02-43f9-ac6f-2c95f64b6585" xlink:to="loc_us-gaap_NoninterestIncome_aebe2f51-2ec4-46ab-88b9-3b04582629c2" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSBankDepositsDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSBankDepositsDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSBankDepositsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_2abde127-4387-40ae-ac71-2437134a76d7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_cf835f30-e4dc-41cb-8a0f-f969ea108529" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_2abde127-4387-40ae-ac71-2437134a76d7" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_cf835f30-e4dc-41cb-8a0f-f969ea108529" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_78794845-d69a-4ca6-89ff-cb33217a58b3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_cf835f30-e4dc-41cb-8a0f-f969ea108529" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_78794845-d69a-4ca6-89ff-cb33217a58b3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_78794845-d69a-4ca6-89ff-cb33217a58b3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_78794845-d69a-4ca6-89ff-cb33217a58b3" xlink:to="loc_us-gaap_RelatedPartyDomain_78794845-d69a-4ca6-89ff-cb33217a58b3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_43b69de1-425e-4b7f-8368-6ac015750024" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_78794845-d69a-4ca6-89ff-cb33217a58b3" xlink:to="loc_us-gaap_RelatedPartyDomain_43b69de1-425e-4b7f-8368-6ac015750024" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_OfficersAndDirectorsMember_be829cc8-1a9a-41fa-803b-2b74af74db23" xlink:href="newt-20241231.xsd#newt_OfficersAndDirectorsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_43b69de1-425e-4b7f-8368-6ac015750024" xlink:to="loc_newt_OfficersAndDirectorsMember_be829cc8-1a9a-41fa-803b-2b74af74db23" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FederalDepositInsuranceCorporationInsuredDeposits_be5496b7-a71b-41cd-96c8-e26f9120fcbf" xlink:href="newt-20241231.xsd#newt_FederalDepositInsuranceCorporationInsuredDeposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_2abde127-4387-40ae-ac71-2437134a76d7" xlink:to="loc_newt_FederalDepositInsuranceCorporationInsuredDeposits_be5496b7-a71b-41cd-96c8-e26f9120fcbf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NonFederalDepositInsuranceCorporationInsuredDeposits_8d9ae5fc-73b2-460e-a76d-d75dc2d91e1b" xlink:href="newt-20241231.xsd#newt_NonFederalDepositInsuranceCorporationInsuredDeposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_2abde127-4387-40ae-ac71-2437134a76d7" xlink:to="loc_newt_NonFederalDepositInsuranceCorporationInsuredDeposits_8d9ae5fc-73b2-460e-a76d-d75dc2d91e1b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Deposits_06c94592-adda-4b76-a991-1e3457196db3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Deposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_2abde127-4387-40ae-ac71-2437134a76d7" xlink:to="loc_us-gaap_Deposits_06c94592-adda-4b76-a991-1e3457196db3" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/TRANSACTIONSWITHAFFILIATEDCOMPANIESANDRELATEDPARTYTRANSACTIONSNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_2d7c3f56-9b9a-493b-8940-c0726659728a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_e9ad5eaf-f7bf-4c82-8cd8-12ff807c6631" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_2d7c3f56-9b9a-493b-8940-c0726659728a" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_e9ad5eaf-f7bf-4c82-8cd8-12ff807c6631" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_6b13ffb2-302c-4542-b5d5-11cee0a0b1d4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_e9ad5eaf-f7bf-4c82-8cd8-12ff807c6631" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_6b13ffb2-302c-4542-b5d5-11cee0a0b1d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_6b13ffb2-302c-4542-b5d5-11cee0a0b1d4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_6b13ffb2-302c-4542-b5d5-11cee0a0b1d4" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_6b13ffb2-302c-4542-b5d5-11cee0a0b1d4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_e8434f54-5e4e-4561-a2c7-e9cc3803d155" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_6b13ffb2-302c-4542-b5d5-11cee0a0b1d4" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_e8434f54-5e4e-4561-a2c7-e9cc3803d155" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_AnnualCompensationMember_c808e6c9-70de-4082-b395-3384528bc51a" xlink:href="newt-20241231.xsd#newt_AnnualCompensationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_e8434f54-5e4e-4561-a2c7-e9cc3803d155" xlink:to="loc_newt_AnnualCompensationMember_c808e6c9-70de-4082-b395-3384528bc51a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_676262e3-ec30-405f-b4af-7b186c3adf6d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_e9ad5eaf-f7bf-4c82-8cd8-12ff807c6631" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_676262e3-ec30-405f-b4af-7b186c3adf6d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_676262e3-ec30-405f-b4af-7b186c3adf6d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_676262e3-ec30-405f-b4af-7b186c3adf6d" xlink:to="loc_us-gaap_RelatedPartyDomain_676262e3-ec30-405f-b4af-7b186c3adf6d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_05cb7240-0458-40ca-8512-72cfa179051d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_676262e3-ec30-405f-b4af-7b186c3adf6d" xlink:to="loc_us-gaap_RelatedPartyDomain_05cb7240-0458-40ca-8512-72cfa179051d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CEONephewMember_32a1b6ae-d9c5-444c-a8cc-f77eaca23c13" xlink:href="newt-20241231.xsd#newt_CEONephewMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_05cb7240-0458-40ca-8512-72cfa179051d" xlink:to="loc_newt_CEONephewMember_32a1b6ae-d9c5-444c-a8cc-f77eaca23c13" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CAOSisterMember_5151dee7-bb3e-4fa7-b73b-ed05b8f32a10" xlink:href="newt-20241231.xsd#newt_CAOSisterMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_05cb7240-0458-40ca-8512-72cfa179051d" xlink:to="loc_newt_CAOSisterMember_5151dee7-bb3e-4fa7-b73b-ed05b8f32a10" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_4c90292d-5897-4840-8069-640a2be1318d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionAmountsOfTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_2d7c3f56-9b9a-493b-8940-c0726659728a" xlink:to="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_4c90292d-5897-4840-8069-640a2be1318d" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/SERVICINGASSETSLoansServicedDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#SERVICINGASSETSLoansServicedDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/SERVICINGASSETSLoansServicedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetsAtFairValueLineItems_7e9af52e-7fbd-4fce-b306-3186558efda9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetsAtFairValueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetsAtFairValueTable_882fece8-afa0-492b-b05d-5d5d8fc6fa01" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetsAtFairValueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueLineItems_7e9af52e-7fbd-4fce-b306-3186558efda9" xlink:to="loc_us-gaap_ServicingAssetsAtFairValueTable_882fece8-afa0-492b-b05d-5d5d8fc6fa01" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_e7f9d5ef-0968-4a6b-888a-763e00e9b390" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueTable_882fece8-afa0-492b-b05d-5d5d8fc6fa01" xlink:to="loc_us-gaap_FinancialInstrumentAxis_e7f9d5ef-0968-4a6b-888a-763e00e9b390" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_e7f9d5ef-0968-4a6b-888a-763e00e9b390_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_e7f9d5ef-0968-4a6b-888a-763e00e9b390" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_e7f9d5ef-0968-4a6b-888a-763e00e9b390_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_8f80ffec-486e-44c1-b4b9-f6f0ba799ef0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_e7f9d5ef-0968-4a6b-888a-763e00e9b390" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_8f80ffec-486e-44c1-b4b9-f6f0ba799ef0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanMember_f29f62d6-2b7e-46e8-af14-85190d808923" xlink:href="newt-20241231.xsd#newt_SBA7aLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_8f80ffec-486e-44c1-b4b9-f6f0ba799ef0" xlink:to="loc_newt_SBA7aLoanMember_f29f62d6-2b7e-46e8-af14-85190d808923" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ALPLoansMember_a8ca9291-076c-4c43-9b7d-9810ef9f1cbd" xlink:href="newt-20241231.xsd#newt_ALPLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_8f80ffec-486e-44c1-b4b9-f6f0ba799ef0" xlink:to="loc_newt_ALPLoansMember_a8ca9291-076c-4c43-9b7d-9810ef9f1cbd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A504LoanMember_0016ab62-3a0e-408d-8ca1-c85e6ea823ff" xlink:href="newt-20241231.xsd#newt_A504LoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_8f80ffec-486e-44c1-b4b9-f6f0ba799ef0" xlink:to="loc_newt_A504LoanMember_0016ab62-3a0e-408d-8ca1-c85e6ea823ff" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ServicingAssetLoansServiced_75120e67-f3cc-45e9-944e-21534f8eee0e" xlink:href="newt-20241231.xsd#newt_ServicingAssetLoansServiced"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueLineItems_7e9af52e-7fbd-4fce-b306-3186558efda9" xlink:to="loc_newt_ServicingAssetLoansServiced_75120e67-f3cc-45e9-944e-21534f8eee0e" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/SERVICINGASSETSFairValueandValuationAssumptionsDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#SERVICINGASSETSFairValueandValuationAssumptionsDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/SERVICINGASSETSFairValueandValuationAssumptionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetsAtFairValueLineItems_285ec0e7-410f-4de4-9b75-16bc59d9e202" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetsAtFairValueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetsAtFairValueTable_fb8706b1-4673-4fbd-a06f-39699ec13cce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetsAtFairValueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueLineItems_285ec0e7-410f-4de4-9b75-16bc59d9e202" xlink:to="loc_us-gaap_ServicingAssetsAtFairValueTable_fb8706b1-4673-4fbd-a06f-39699ec13cce" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_3b2aa557-6687-4b5a-a587-637dd0326c82" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueTable_fb8706b1-4673-4fbd-a06f-39699ec13cce" xlink:to="loc_srt_RangeAxis_3b2aa557-6687-4b5a-a587-637dd0326c82" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_3b2aa557-6687-4b5a-a587-637dd0326c82_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_3b2aa557-6687-4b5a-a587-637dd0326c82" xlink:to="loc_srt_RangeMember_3b2aa557-6687-4b5a-a587-637dd0326c82_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_43b40c2d-2e8b-4da4-8437-29e09da54056" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_3b2aa557-6687-4b5a-a587-637dd0326c82" xlink:to="loc_srt_RangeMember_43b40c2d-2e8b-4da4-8437-29e09da54056" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_WeightedAverageMember_48d6f57b-bcb0-4dc1-9265-6867340a20b2" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_WeightedAverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_43b40c2d-2e8b-4da4-8437-29e09da54056" xlink:to="loc_srt_WeightedAverageMember_48d6f57b-bcb0-4dc1-9265-6867340a20b2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_a18e631c-88ea-44bb-9773-74c4cefc69ce" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_43b40c2d-2e8b-4da4-8437-29e09da54056" xlink:to="loc_srt_MinimumMember_a18e631c-88ea-44bb-9773-74c4cefc69ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_55333375-e327-482b-b62d-8272095a5545" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_43b40c2d-2e8b-4da4-8437-29e09da54056" xlink:to="loc_srt_MaximumMember_55333375-e327-482b-b62d-8272095a5545" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_5cb0e13c-ffe0-4b7c-a938-49625121d388" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueTable_fb8706b1-4673-4fbd-a06f-39699ec13cce" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_5cb0e13c-ffe0-4b7c-a938-49625121d388" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_5cb0e13c-ffe0-4b7c-a938-49625121d388_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_5cb0e13c-ffe0-4b7c-a938-49625121d388" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_5cb0e13c-ffe0-4b7c-a938-49625121d388_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_363457fc-3357-4a37-ae1c-f4e4698c6143" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_5cb0e13c-ffe0-4b7c-a938-49625121d388" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_363457fc-3357-4a37-ae1c-f4e4698c6143" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputDiscountRateMember_7f4646f5-c7eb-498b-8d4d-173f02365b6a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputDiscountRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_363457fc-3357-4a37-ae1c-f4e4698c6143" xlink:to="loc_us-gaap_MeasurementInputDiscountRateMember_7f4646f5-c7eb-498b-8d4d-173f02365b6a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputPrepaymentRateMember_a68eb4d9-0471-4aa3-9947-2d87a870ecd4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputPrepaymentRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_363457fc-3357-4a37-ae1c-f4e4698c6143" xlink:to="loc_us-gaap_MeasurementInputPrepaymentRateMember_a68eb4d9-0471-4aa3-9947-2d87a870ecd4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputDefaultRateMember_deb7b891-8f9a-4bb4-902b-21c64ce56b15" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputDefaultRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_363457fc-3357-4a37-ae1c-f4e4698c6143" xlink:to="loc_us-gaap_MeasurementInputDefaultRateMember_deb7b891-8f9a-4bb4-902b-21c64ce56b15" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis_fecc37db-7205-4c64-bf96-0f53db71b2ae" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueTable_fb8706b1-4673-4fbd-a06f-39699ec13cce" xlink:to="loc_us-gaap_ValuationTechniqueAxis_fecc37db-7205-4c64-bf96-0f53db71b2ae" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_fecc37db-7205-4c64-bf96-0f53db71b2ae_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationTechniqueAxis_fecc37db-7205-4c64-bf96-0f53db71b2ae" xlink:to="loc_us-gaap_ValuationTechniqueDomain_fecc37db-7205-4c64-bf96-0f53db71b2ae_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_494e5e66-cffe-4cf4-acf4-659642af2ff8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationTechniqueAxis_fecc37db-7205-4c64-bf96-0f53db71b2ae" xlink:to="loc_us-gaap_ValuationTechniqueDomain_494e5e66-cffe-4cf4-acf4-659642af2ff8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FairValueMember_bd9b037f-b8ec-4eb3-a334-305e99c6bd85" xlink:href="newt-20241231.xsd#newt_FairValueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_494e5e66-cffe-4cf4-acf4-659642af2ff8" xlink:to="loc_newt_FairValueMember_bd9b037f-b8ec-4eb3-a334-305e99c6bd85" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LowerOfCostOrMarketMember_1af5bce7-d042-4644-b6ec-476248ae634d" xlink:href="newt-20241231.xsd#newt_LowerOfCostOrMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_494e5e66-cffe-4cf4-acf4-659642af2ff8" xlink:to="loc_newt_LowerOfCostOrMarketMember_1af5bce7-d042-4644-b6ec-476248ae634d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAsset_6288d36a-b380-4639-ae44-1ff27e4488da" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueLineItems_285ec0e7-410f-4de4-9b75-16bc59d9e202" xlink:to="loc_us-gaap_ServicingAsset_6288d36a-b380-4639-ae44-1ff27e4488da" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetMeasurementInput_d0ed3420-305b-4c20-a7cb-110153c89369" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueLineItems_285ec0e7-410f-4de4-9b75-16bc59d9e202" xlink:to="loc_us-gaap_ServicingAssetMeasurementInput_d0ed3420-305b-4c20-a7cb-110153c89369" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/SERVICINGASSETSServicingFeeIncomeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#SERVICINGASSETSServicingFeeIncomeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/SERVICINGASSETSServicingFeeIncomeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetsAtFairValueLineItems_253443ba-3831-43ba-9e4c-abbcbb352abd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetsAtFairValueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetsAtFairValueTable_8f59ec46-239e-4a81-8ccf-ec81b7d31a3f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetsAtFairValueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueLineItems_253443ba-3831-43ba-9e4c-abbcbb352abd" xlink:to="loc_us-gaap_ServicingAssetsAtFairValueTable_8f59ec46-239e-4a81-8ccf-ec81b7d31a3f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_adea79b4-77c4-49c9-8690-cfd8e18337da" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueTable_8f59ec46-239e-4a81-8ccf-ec81b7d31a3f" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_adea79b4-77c4-49c9-8690-cfd8e18337da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_adea79b4-77c4-49c9-8690-cfd8e18337da_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_adea79b4-77c4-49c9-8690-cfd8e18337da" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_adea79b4-77c4-49c9-8690-cfd8e18337da_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_0c1e47e3-d892-4432-9634-df5f9ac64852" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_adea79b4-77c4-49c9-8690-cfd8e18337da" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_0c1e47e3-d892-4432-9634-df5f9ac64852" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_1e619e34-d287-49a4-8df2-245844dda955" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentUnaffiliatedIssuerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_0c1e47e3-d892-4432-9634-df5f9ac64852" xlink:to="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_1e619e34-d287-49a4-8df2-245844dda955" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets_c6d04354-25e5-420f-a602-813e29fe0e2c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ServicingAssetsAtFairValueLineItems_253443ba-3831-43ba-9e4c-abbcbb352abd" xlink:to="loc_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets_c6d04354-25e5-420f-a602-813e29fe0e2c" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/GOODWILLANDINTANGIBLEASSETSGoodwillDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#GOODWILLANDINTANGIBLEASSETSGoodwillDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/GOODWILLANDINTANGIBLEASSETSGoodwillDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillLineItems_34624960-8e97-497e-927c-fa7900674a62" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_b8e31ce4-af85-4304-8664-2f7c845f0051" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfGoodwillTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_34624960-8e97-497e-927c-fa7900674a62" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_b8e31ce4-af85-4304-8664-2f7c845f0051" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_3269504c-8f5b-478d-91f4-0d5a217af953" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_b8e31ce4-af85-4304-8664-2f7c845f0051" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_3269504c-8f5b-478d-91f4-0d5a217af953" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_3269504c-8f5b-478d-91f4-0d5a217af953_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_3269504c-8f5b-478d-91f4-0d5a217af953" xlink:to="loc_us-gaap_SegmentDomain_3269504c-8f5b-478d-91f4-0d5a217af953_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_cc9b29a5-b208-4ae3-92cf-ec24d8f0d1d9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_3269504c-8f5b-478d-91f4-0d5a217af953" xlink:to="loc_us-gaap_SegmentDomain_cc9b29a5-b208-4ae3-92cf-ec24d8f0d1d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BankingSegmentMember_0930a5a8-a46c-41ee-a0f0-f3fe8b5b26ca" xlink:href="newt-20241231.xsd#newt_BankingSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_cc9b29a5-b208-4ae3-92cf-ec24d8f0d1d9" xlink:to="loc_newt_BankingSegmentMember_0930a5a8-a46c-41ee-a0f0-f3fe8b5b26ca" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PaymentsMember_bdb4a38d-2075-4001-aa83-69b7add00fe1" xlink:href="newt-20241231.xsd#newt_PaymentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_cc9b29a5-b208-4ae3-92cf-ec24d8f0d1d9" xlink:to="loc_newt_PaymentsMember_bdb4a38d-2075-4001-aa83-69b7add00fe1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_TechnologyMember_98fa9963-ffbe-42b5-bfb9-8656239992db" xlink:href="newt-20241231.xsd#newt_TechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_cc9b29a5-b208-4ae3-92cf-ec24d8f0d1d9" xlink:to="loc_newt_TechnologyMember_98fa9963-ffbe-42b5-bfb9-8656239992db" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_0aea2923-842a-41c6-9312-b6921d3e90bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_34624960-8e97-497e-927c-fa7900674a62" xlink:to="loc_us-gaap_Goodwill_0aea2923-842a-41c6-9312-b6921d3e90bc" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/GOODWILLANDINTANGIBLEASSETSNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#GOODWILLANDINTANGIBLEASSETSNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/GOODWILLANDINTANGIBLEASSETSNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillLineItems_ff12029e-00d1-49b3-b0c4-4997b2491ad5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_c945b33d-cb0c-45c6-8622-ceea55fa74c8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfGoodwillTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_ff12029e-00d1-49b3-b0c4-4997b2491ad5" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_c945b33d-cb0c-45c6-8622-ceea55fa74c8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_c3956161-73b9-4e1a-8876-d31758e40bf8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_c945b33d-cb0c-45c6-8622-ceea55fa74c8" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_c3956161-73b9-4e1a-8876-d31758e40bf8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_c3956161-73b9-4e1a-8876-d31758e40bf8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_c3956161-73b9-4e1a-8876-d31758e40bf8" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_c3956161-73b9-4e1a-8876-d31758e40bf8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_5cec470a-b4fa-41cf-9bcc-24104209487f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_c3956161-73b9-4e1a-8876-d31758e40bf8" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_5cec470a-b4fa-41cf-9bcc-24104209487f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NationalBankOfNewYorkCityMember_4b9c4a44-544b-4630-9556-29c0cdac0d78" xlink:href="newt-20241231.xsd#newt_NationalBankOfNewYorkCityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_5cec470a-b4fa-41cf-9bcc-24104209487f" xlink:to="loc_newt_NationalBankOfNewYorkCityMember_4b9c4a44-544b-4630-9556-29c0cdac0d78" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_3807e810-f9df-4054-9043-dd969cb265d3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_c945b33d-cb0c-45c6-8622-ceea55fa74c8" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_3807e810-f9df-4054-9043-dd969cb265d3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_3807e810-f9df-4054-9043-dd969cb265d3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_3807e810-f9df-4054-9043-dd969cb265d3" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_3807e810-f9df-4054-9043-dd969cb265d3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_a25e14b7-c0b5-4c40-8b68-0b5d4e1102fb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_3807e810-f9df-4054-9043-dd969cb265d3" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_a25e14b7-c0b5-4c40-8b68-0b5d4e1102fb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CoreDepositsMember_50247bb6-7765-4aa8-97dd-a46970699d07" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CoreDepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_a25e14b7-c0b5-4c40-8b68-0b5d4e1102fb" xlink:to="loc_us-gaap_CoreDepositsMember_50247bb6-7765-4aa8-97dd-a46970699d07" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerListsMember_b2a43ebc-3e67-4716-a067-86f233b3220b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CustomerListsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_a25e14b7-c0b5-4c40-8b68-0b5d4e1102fb" xlink:to="loc_us-gaap_CustomerListsMember_b2a43ebc-3e67-4716-a067-86f233b3220b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAcquiredDuringPeriod_010803a6-e5ca-4848-89b7-978166742662" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillAcquiredDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_ff12029e-00d1-49b3-b0c4-4997b2491ad5" xlink:to="loc_us-gaap_GoodwillAcquiredDuringPeriod_010803a6-e5ca-4848-89b7-978166742662" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_48b4f8d4-cbe8-42b3-9939-ae36261109a2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_ff12029e-00d1-49b3-b0c4-4997b2491ad5" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_48b4f8d4-cbe8-42b3-9939-ae36261109a2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_7772c42b-1bfe-4945-8dc0-d576107a36f9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_ff12029e-00d1-49b3-b0c4-4997b2491ad5" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_7772c42b-1bfe-4945-8dc0-d576107a36f9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairmentOfIntangibleAssetFiniteLivedStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration_5233b070-08df-44ae-8fc6-214081b8ee01" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ImpairmentOfIntangibleAssetFiniteLivedStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_ff12029e-00d1-49b3-b0c4-4997b2491ad5" xlink:to="loc_us-gaap_ImpairmentOfIntangibleAssetFiniteLivedStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration_5233b070-08df-44ae-8fc6-214081b8ee01" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/GOODWILLANDINTANGIBLEASSETSIntangibleAssetsDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#GOODWILLANDINTANGIBLEASSETSIntangibleAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/GOODWILLANDINTANGIBLEASSETSIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_8ea6b41e-c31f-485d-9021-ec8c95ec0227" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_7b1ce6d7-a3ce-48ff-855d-0592570bc880" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_8ea6b41e-c31f-485d-9021-ec8c95ec0227" xlink:to="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_7b1ce6d7-a3ce-48ff-855d-0592570bc880" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_a86d9a93-62f3-4577-89b3-82d2d06d3042" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_7b1ce6d7-a3ce-48ff-855d-0592570bc880" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_a86d9a93-62f3-4577-89b3-82d2d06d3042" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_a86d9a93-62f3-4577-89b3-82d2d06d3042_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_a86d9a93-62f3-4577-89b3-82d2d06d3042" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_a86d9a93-62f3-4577-89b3-82d2d06d3042_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_deca0f13-95e4-43da-8916-05ccc9d594d3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_a86d9a93-62f3-4577-89b3-82d2d06d3042" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_deca0f13-95e4-43da-8916-05ccc9d594d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CoreDepositsMember_48197ce1-aafd-4049-92af-7532f628c105" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CoreDepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_deca0f13-95e4-43da-8916-05ccc9d594d3" xlink:to="loc_us-gaap_CoreDepositsMember_48197ce1-aafd-4049-92af-7532f628c105" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerListsMember_1fdfc580-b6e5-4a52-9de9-2d80c3a0b47b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CustomerListsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_deca0f13-95e4-43da-8916-05ccc9d594d3" xlink:to="loc_us-gaap_CustomerListsMember_1fdfc580-b6e5-4a52-9de9-2d80c3a0b47b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_90fc61ec-3b07-4a3a-9773-b87fcd5feb07" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_7b1ce6d7-a3ce-48ff-855d-0592570bc880" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_90fc61ec-3b07-4a3a-9773-b87fcd5feb07" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_90fc61ec-3b07-4a3a-9773-b87fcd5feb07_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_90fc61ec-3b07-4a3a-9773-b87fcd5feb07" xlink:to="loc_us-gaap_SegmentDomain_90fc61ec-3b07-4a3a-9773-b87fcd5feb07_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_5df78e56-d3b4-4a36-9852-137739c0877c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_90fc61ec-3b07-4a3a-9773-b87fcd5feb07" xlink:to="loc_us-gaap_SegmentDomain_5df78e56-d3b4-4a36-9852-137739c0877c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PaymentsMember_46d16a88-a01b-4881-8e97-f8ae7c3a57b0" xlink:href="newt-20241231.xsd#newt_PaymentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_5df78e56-d3b4-4a36-9852-137739c0877c" xlink:to="loc_newt_PaymentsMember_46d16a88-a01b-4881-8e97-f8ae7c3a57b0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_TechnologyMember_329e9409-4eb7-4a96-ab65-03769030ee24" xlink:href="newt-20241231.xsd#newt_TechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_5df78e56-d3b4-4a36-9852-137739c0877c" xlink:to="loc_newt_TechnologyMember_329e9409-4eb7-4a96-ab65-03769030ee24" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_7c08252b-e52a-4567-a967-86089e30c305" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_8ea6b41e-c31f-485d-9021-ec8c95ec0227" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_7c08252b-e52a-4567-a967-86089e30c305" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_71df40e8-f872-4c37-913e-60728b031987" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_8ea6b41e-c31f-485d-9021-ec8c95ec0227" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_71df40e8-f872-4c37-913e-60728b031987" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_72539aec-715f-4b66-9d14-f8e92b0e05bf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_8ea6b41e-c31f-485d-9021-ec8c95ec0227" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_72539aec-715f-4b66-9d14-f8e92b0e05bf" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/ASSETSANDLIABILITIESDIRECTLYASSOCIATEDWITHASSETSHELDFORSALEDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#ASSETSANDLIABILITIESDIRECTLYASSOCIATEDWITHASSETSHELDFORSALEDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/ASSETSANDLIABILITIESDIRECTLYASSOCIATEDWITHASSETSHELDFORSALEDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_9bba27a0-0b48-488b-a94b-df43c461be5c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_3445865b-b2d0-440c-8665-766049828784" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_9bba27a0-0b48-488b-a94b-df43c461be5c" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_3445865b-b2d0-440c-8665-766049828784" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_eafab767-c236-4f67-830a-0bfc57b31ee6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_3445865b-b2d0-440c-8665-766049828784" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_eafab767-c236-4f67-830a-0bfc57b31ee6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_eafab767-c236-4f67-830a-0bfc57b31ee6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_eafab767-c236-4f67-830a-0bfc57b31ee6" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_eafab767-c236-4f67-830a-0bfc57b31ee6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_33b79676-d936-48e8-939b-f305fb00e054" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_eafab767-c236-4f67-830a-0bfc57b31ee6" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_33b79676-d936-48e8-939b-f305fb00e054" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NewtekTechnologySolutionsIncMember_e7687038-6cf5-49a2-a530-b9f47a446ff7" xlink:href="newt-20241231.xsd#newt_NewtekTechnologySolutionsIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_33b79676-d936-48e8-939b-f305fb00e054" xlink:to="loc_newt_NewtekTechnologySolutionsIncMember_e7687038-6cf5-49a2-a530-b9f47a446ff7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_aa1f3746-2ede-448b-963f-1725e8fbe811" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_3445865b-b2d0-440c-8665-766049828784" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_aa1f3746-2ede-448b-963f-1725e8fbe811" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_aa1f3746-2ede-448b-963f-1725e8fbe811_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_aa1f3746-2ede-448b-963f-1725e8fbe811" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_aa1f3746-2ede-448b-963f-1725e8fbe811_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_6dd63834-e28d-4f30-b6b8-027cf7676afb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_aa1f3746-2ede-448b-963f-1725e8fbe811" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_6dd63834-e28d-4f30-b6b8-027cf7676afb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_b8edf831-10f7-4666-b17c-399952476153" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_6dd63834-e28d-4f30-b6b8-027cf7676afb" xlink:to="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_b8edf831-10f7-4666-b17c-399952476153" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_6171423b-c1dd-4976-ada2-cd0586b052f9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_9bba27a0-0b48-488b-a94b-df43c461be5c" xlink:to="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_6171423b-c1dd-4976-ada2-cd0586b052f9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents_723319f5-0ec9-4b6b-9231-0f93002b516c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_6171423b-c1dd-4976-ada2-cd0586b052f9" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents_723319f5-0ec9-4b6b-9231-0f93002b516c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGoodwill1_29de57ad-df24-434a-a142-a0b6e5247e1e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationGoodwill1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_6171423b-c1dd-4976-ada2-cd0586b052f9" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGoodwill1_29de57ad-df24-434a-a142-a0b6e5247e1e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssets_6cd8a6d0-6d26-4423-b9df-3346f7c89b63" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_6171423b-c1dd-4976-ada2-cd0586b052f9" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssets_6cd8a6d0-6d26-4423-b9df-3346f7c89b63" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseRightOfUseAsset_da496890-e64e-44c0-aaae-d32b42cf4f8a" xlink:href="newt-20241231.xsd#newt_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseRightOfUseAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_6171423b-c1dd-4976-ada2-cd0586b052f9" xlink:to="loc_newt_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseRightOfUseAsset_da496890-e64e-44c0-aaae-d32b42cf4f8a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherAssets_ac8fc8a0-c693-4542-a534-ed5fed55e4e5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_6171423b-c1dd-4976-ada2-cd0586b052f9" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherAssets_ac8fc8a0-c693-4542-a534-ed5fed55e4e5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DisposalGroupIncludingDiscontinuedOperationValuationAdjustmentAssets_a9dcd456-547d-4004-afd4-424b88c505ff" xlink:href="newt-20241231.xsd#newt_DisposalGroupIncludingDiscontinuedOperationValuationAdjustmentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_6171423b-c1dd-4976-ada2-cd0586b052f9" xlink:to="loc_newt_DisposalGroupIncludingDiscontinuedOperationValuationAdjustmentAssets_a9dcd456-547d-4004-afd4-424b88c505ff" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation_b5ff69c9-f399-464f-8d79-77f058e36eeb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_6171423b-c1dd-4976-ada2-cd0586b052f9" xlink:to="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation_b5ff69c9-f399-464f-8d79-77f058e36eeb" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8653c721-ddc5-46ef-a782-d492cfc0ea00" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_9bba27a0-0b48-488b-a94b-df43c461be5c" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8653c721-ddc5-46ef-a782-d492cfc0ea00" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseLiabilities_ed43abdc-910f-424a-81c3-00c3187af7f7" xlink:href="newt-20241231.xsd#newt_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8653c721-ddc5-46ef-a782-d492cfc0ea00" xlink:to="loc_newt_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseLiabilities_ed43abdc-910f-424a-81c3-00c3187af7f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationDeferredTaxLiabilities_8374c5fe-cbdc-498f-9c6a-bfe4629f68ed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationDeferredTaxLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8653c721-ddc5-46ef-a782-d492cfc0ea00" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationDeferredTaxLiabilities_8374c5fe-cbdc-498f-9c6a-bfe4629f68ed" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableAndAccruedLiabilities_e3e84c7f-1ecc-4a58-8961-ea8c94ddc7e8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableAndAccruedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8653c721-ddc5-46ef-a782-d492cfc0ea00" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableAndAccruedLiabilities_e3e84c7f-1ecc-4a58-8961-ea8c94ddc7e8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_fe643781-7084-4d7d-8ec3-68a4614ca93e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8653c721-ddc5-46ef-a782-d492cfc0ea00" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_fe643781-7084-4d7d-8ec3-68a4614ca93e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsAbstract_d6da497f-3075-44e6-b2ad-9ea94a2aad72" xlink:href="newt-20241231.xsd#newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_9bba27a0-0b48-488b-a94b-df43c461be5c" xlink:to="loc_newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsAbstract_d6da497f-3075-44e6-b2ad-9ea94a2aad72" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsGross_36dc8af4-babb-43db-83cf-b2cab286a67c" xlink:href="newt-20241231.xsd#newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsAbstract_d6da497f-3075-44e6-b2ad-9ea94a2aad72" xlink:to="loc_newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsGross_36dc8af4-babb-43db-83cf-b2cab286a67c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsAccumulatedAmortization_99b819c0-3b52-4120-b586-a483c070b951" xlink:href="newt-20241231.xsd#newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsAbstract_d6da497f-3075-44e6-b2ad-9ea94a2aad72" xlink:to="loc_newt_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsAccumulatedAmortization_99b819c0-3b52-4120-b586-a483c070b951" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssets_42dc5542-5652-4fed-ba38-aea0d3d33b48" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssets"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/FAIRVALUEMEASUREMENTSFairValueLevelsDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#FAIRVALUEMEASUREMENTSFairValueLevelsDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/FAIRVALUEMEASUREMENTSFairValueLevelsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_f10efc3d-6d23-473e-b4e4-0c5db824e584" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_bb024816-b12c-435b-a132-74d39d321ca2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_f10efc3d-6d23-473e-b4e4-0c5db824e584" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_bb024816-b12c-435b-a132-74d39d321ca2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_fbebdb1f-0278-4514-8c5e-861eb7e77807" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_bb024816-b12c-435b-a132-74d39d321ca2" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_fbebdb1f-0278-4514-8c5e-861eb7e77807" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_fbebdb1f-0278-4514-8c5e-861eb7e77807_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_fbebdb1f-0278-4514-8c5e-861eb7e77807" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_fbebdb1f-0278-4514-8c5e-861eb7e77807_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_df5919f1-0782-4026-a1ec-84a57f256a09" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_fbebdb1f-0278-4514-8c5e-861eb7e77807" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_df5919f1-0782-4026-a1ec-84a57f256a09" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_04541988-b788-4f06-bfbd-5fdb6620e758" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_df5919f1-0782-4026-a1ec-84a57f256a09" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_04541988-b788-4f06-bfbd-5fdb6620e758" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_4095aee4-f7ce-41ae-93e3-4f11c7fdc1b5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_df5919f1-0782-4026-a1ec-84a57f256a09" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_4095aee4-f7ce-41ae-93e3-4f11c7fdc1b5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_83e0fe5a-a12d-4cd8-915c-c047ca193b38" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_df5919f1-0782-4026-a1ec-84a57f256a09" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_83e0fe5a-a12d-4cd8-915c-c047ca193b38" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_b8f09698-ead6-4702-9d75-813f771e39dd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_bb024816-b12c-435b-a132-74d39d321ca2" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_b8f09698-ead6-4702-9d75-813f771e39dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_b8f09698-ead6-4702-9d75-813f771e39dd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_b8f09698-ead6-4702-9d75-813f771e39dd" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_b8f09698-ead6-4702-9d75-813f771e39dd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_23773ad4-b334-428d-8194-21eccfda6533" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_b8f09698-ead6-4702-9d75-813f771e39dd" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_23773ad4-b334-428d-8194-21eccfda6533" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember_8787fad5-b77a-4e92-903d-9001903002cf" xlink:href="newt-20241231.xsd#newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_23773ad4-b334-428d-8194-21eccfda6533" xlink:to="loc_newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember_8787fad5-b77a-4e92-903d-9001903002cf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_e9d516e7-b62d-4d62-8f6c-2cd42fa8b7da" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_bb024816-b12c-435b-a132-74d39d321ca2" xlink:to="loc_us-gaap_FinancialInstrumentAxis_e9d516e7-b62d-4d62-8f6c-2cd42fa8b7da" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_e9d516e7-b62d-4d62-8f6c-2cd42fa8b7da_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_e9d516e7-b62d-4d62-8f6c-2cd42fa8b7da" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_e9d516e7-b62d-4d62-8f6c-2cd42fa8b7da_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_31209214-15ce-4bb3-8422-3fbbc804d946" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_e9d516e7-b62d-4d62-8f6c-2cd42fa8b7da" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_31209214-15ce-4bb3-8422-3fbbc804d946" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_d25d663c-29bc-487d-a804-fa3d580a7dfe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_31209214-15ce-4bb3-8422-3fbbc804d946" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_d25d663c-29bc-487d-a804-fa3d580a7dfe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_3cd6ac33-2319-441d-8851-8e7472d680ad" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_31209214-15ce-4bb3-8422-3fbbc804d946" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_3cd6ac33-2319-441d-8851-8e7472d680ad" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LoansHeldForSaleMember_e711d8f6-1f9f-4a9f-84d2-d5f3dc4e0eb2" xlink:href="newt-20241231.xsd#newt_LoansHeldForSaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_31209214-15ce-4bb3-8422-3fbbc804d946" xlink:to="loc_newt_LoansHeldForSaleMember_e711d8f6-1f9f-4a9f-84d2-d5f3dc4e0eb2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LoansHeldForInvestmentMember_3f32c8d7-87c0-4f15-9284-1fe7ccf6bd72" xlink:href="newt-20241231.xsd#newt_LoansHeldForInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_31209214-15ce-4bb3-8422-3fbbc804d946" xlink:to="loc_newt_LoansHeldForInvestmentMember_3f32c8d7-87c0-4f15-9284-1fe7ccf6bd72" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CashAndDueFromBanksMember_cb095f3b-a200-452a-a42f-9c608c528002" xlink:href="newt-20241231.xsd#newt_CashAndDueFromBanksMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_31209214-15ce-4bb3-8422-3fbbc804d946" xlink:to="loc_newt_CashAndDueFromBanksMember_cb095f3b-a200-452a-a42f-9c608c528002" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_RestrictedCashMember_3251b2bc-aed8-4f2b-8629-e41416713673" xlink:href="newt-20241231.xsd#newt_RestrictedCashMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_31209214-15ce-4bb3-8422-3fbbc804d946" xlink:to="loc_newt_RestrictedCashMember_3251b2bc-aed8-4f2b-8629-e41416713673" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestBearingDepositsMember_bc97c0d8-7dbe-40ba-80ee-beae081f66d7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestBearingDepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_31209214-15ce-4bb3-8422-3fbbc804d946" xlink:to="loc_us-gaap_InterestBearingDepositsMember_bc97c0d8-7dbe-40ba-80ee-beae081f66d7" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_f2fcffd0-cd06-4b22-80bf-7a2802800957" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_31209214-15ce-4bb3-8422-3fbbc804d946" xlink:to="loc_us-gaap_WarrantMember_f2fcffd0-cd06-4b22-80bf-7a2802800957" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_f10efc3d-6d23-473e-b4e4-0c5db824e584" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_b8cd3d97-b6b4-4bd4-974e-5a9e35c82fe7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_b8cd3d97-b6b4-4bd4-974e-5a9e35c82fe7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableHeldForSaleAmount_daf694f8-5657-43b6-88e2-4ff994e2c15d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LoansReceivableHeldForSaleAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:to="loc_us-gaap_LoansReceivableHeldForSaleAmount_daf694f8-5657-43b6-88e2-4ff994e2c15d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure_088e859e-c5ab-446a-a50b-b612b1af6ce0" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:to="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure_088e859e-c5ab-446a-a50b-b612b1af6ce0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherRealEstate_b6908389-bb39-4536-a817-bbf237000614" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:to="loc_us-gaap_OtherRealEstate_b6908389-bb39-4536-a817-bbf237000614" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetAtFairValueAmount_aad30b69-97fb-4efb-b824-05312baa2043" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetAtFairValueAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:to="loc_us-gaap_ServicingAssetAtFairValueAmount_aad30b69-97fb-4efb-b824-05312baa2043" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_93d53948-7bcb-4b54-b4b3-4c833ec49c9d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_93d53948-7bcb-4b54-b4b3-4c833ec49c9d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure_2c5e0664-b359-4909-a2d3-d74cb9c3cfc5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:to="loc_us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure_2c5e0664-b359-4909-a2d3-d74cb9c3cfc5" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetStatementOfFinancialPositionExtensibleEnumeration_cd7fcc09-95f6-4770-a008-d0176f4cc76f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeAssetStatementOfFinancialPositionExtensibleEnumeration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:to="loc_us-gaap_DerivativeAssetStatementOfFinancialPositionExtensibleEnumeration_cd7fcc09-95f6-4770-a008-d0176f4cc76f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_b11aeb07-641c-4b85-a26d-8d1c683977e8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:to="loc_us-gaap_DerivativeAssets_b11aeb07-641c-4b85-a26d-8d1c683977e8" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_111da19d-3579-4c3b-b308-aba82210a753" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_ad7ff69b-b0a6-4385-a979-ff7ced8790d1" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_111da19d-3579-4c3b-b308-aba82210a753" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_81151522-3dd1-4517-a4c6-d07b5badd26c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_f10efc3d-6d23-473e-b4e4-0c5db824e584" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_81151522-3dd1-4517-a4c6-d07b5badd26c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantsAndRightsOutstanding_e465233f-bb32-4f23-88ef-774424f23183" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_WarrantsAndRightsOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_81151522-3dd1-4517-a4c6-d07b5badd26c" xlink:to="loc_us-gaap_WarrantsAndRightsOutstanding_e465233f-bb32-4f23-88ef-774424f23183" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_0da9a415-5869-4ea2-a7b4-a414fef42e20" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_81151522-3dd1-4517-a4c6-d07b5badd26c" xlink:to="loc_us-gaap_DerivativeLiabilities_0da9a415-5869-4ea2-a7b4-a414fef42e20" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityStatementOfFinancialPositionExtensibleEnumeration_f12e94c6-1bca-4170-97d5-c45d769cdab1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeLiabilityStatementOfFinancialPositionExtensibleEnumeration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_81151522-3dd1-4517-a4c6-d07b5badd26c" xlink:to="loc_us-gaap_DerivativeLiabilityStatementOfFinancialPositionExtensibleEnumeration_f12e94c6-1bca-4170-97d5-c45d769cdab1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_c67fbf60-f12c-4dab-8c95-e5e1f9d99f65" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_81151522-3dd1-4517-a4c6-d07b5badd26c" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_c67fbf60-f12c-4dab-8c95-e5e1f9d99f65" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:href="newt-20241231.xsd#newt_CarryingAmountAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_f10efc3d-6d23-473e-b4e4-0c5db824e584" xlink:to="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Cash_f35221ed-8bcd-48f7-94a6-30bf155a3c1a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Cash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:to="loc_us-gaap_Cash_f35221ed-8bcd-48f7-94a6-30bf155a3c1a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCash_e4dfa50c-186f-48e5-bb54-abcdc73ecb90" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:to="loc_us-gaap_RestrictedCash_e4dfa50c-186f-48e5-bb54-abcdc73ecb90" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DueFromBanks_4cdbbed6-ae52-4717-ac95-d3d1eb6aee69" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DueFromBanks"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:to="loc_us-gaap_DueFromBanks_4cdbbed6-ae52-4717-ac95-d3d1eb6aee69" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketableSecurities_32c54d25-833c-45cd-8e97-13d73a141d07" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketableSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:to="loc_us-gaap_MarketableSecurities_32c54d25-833c-45cd-8e97-13d73a141d07" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableHeldForSaleAmount_bb47d856-4652-4453-ba9b-a8bc9b983489" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LoansReceivableHeldForSaleAmount"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableHeldForSaleLowerOfCostOrMarket_0cba50cb-3dc6-4e61-b575-55003343cf8b" xlink:href="newt-20241231.xsd#newt_FinancingReceivableHeldForSaleLowerOfCostOrMarket"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:to="loc_newt_FinancingReceivableHeldForSaleLowerOfCostOrMarket_0cba50cb-3dc6-4e61-b575-55003343cf8b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure_9c7ff55a-db55-433b-b32f-ba52cd6e9725" xlink:href="newt-20241231.xsd#newt_FinancingReceivableBeforeAllowanceForCreditLossFairValueDisclosure"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_bd87f3b8-f399-41e2-a7a2-df6808bf4563" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_bd87f3b8-f399-41e2-a7a2-df6808bf4563" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankStockAndFederalReserveBankStock_f7c232f7-4065-4142-8391-508b5bc6486c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FederalHomeLoanBankStockAndFederalReserveBankStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:to="loc_us-gaap_FederalHomeLoanBankStockAndFederalReserveBankStock_f7c232f7-4065-4142-8391-508b5bc6486c" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_2f0c2e2f-0b1f-4f00-8c5c-6983ecb0aff1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestBearingDomesticDepositTimeDeposits_c6cc0ccf-7e1e-40fa-95b5-14dfccbe820c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestBearingDomesticDepositTimeDeposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:to="loc_us-gaap_InterestBearingDomesticDepositTimeDeposits_c6cc0ccf-7e1e-40fa-95b5-14dfccbe820c" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_af380f59-8bc7-42c7-8f42-355deb738887" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_CarryingAmountAbstract_2e058399-ce94-448b-a1de-833a05d990e8" xlink:to="loc_us-gaap_LongTermDebt_af380f59-8bc7-42c7-8f42-355deb738887" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueNetAssetLiabilityAbstract_bf02a0cf-485f-4729-90dc-7d2dca8bd472" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueNetAssetLiabilityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_f10efc3d-6d23-473e-b4e4-0c5db824e584" xlink:to="loc_us-gaap_FairValueNetAssetLiabilityAbstract_bf02a0cf-485f-4729-90dc-7d2dca8bd472" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_58760edb-d19e-4bc9-8532-8301bbc93daa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueNetAssetLiabilityAbstract_bf02a0cf-485f-4729-90dc-7d2dca8bd472" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_58760edb-d19e-4bc9-8532-8301bbc93daa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_MarketableSecuritiesFairValueDisclosure_d7011d26-7992-4203-8e0d-477527e2aeb2" xlink:href="newt-20241231.xsd#newt_MarketableSecuritiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueNetAssetLiabilityAbstract_bf02a0cf-485f-4729-90dc-7d2dca8bd472" xlink:to="loc_newt_MarketableSecuritiesFairValueDisclosure_d7011d26-7992-4203-8e0d-477527e2aeb2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableHeldForSaleFairValueDisclosure_31b5282b-8056-410b-92f1-199ea6e31851" xlink:href="newt-20241231.xsd#newt_FinancingReceivableHeldForSaleFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueNetAssetLiabilityAbstract_bf02a0cf-485f-4729-90dc-7d2dca8bd472" xlink:to="loc_newt_FinancingReceivableHeldForSaleFairValueDisclosure_31b5282b-8056-410b-92f1-199ea6e31851" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableHeldForSaleLowerOfCostOrMarketFairValueDisclosure_196abce5-487d-4a35-9a5a-de0e367ce757" xlink:href="newt-20241231.xsd#newt_FinancingReceivableHeldForSaleLowerOfCostOrMarketFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueNetAssetLiabilityAbstract_bf02a0cf-485f-4729-90dc-7d2dca8bd472" xlink:to="loc_newt_FinancingReceivableHeldForSaleLowerOfCostOrMarketFairValueDisclosure_196abce5-487d-4a35-9a5a-de0e367ce757" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FinancingReceivableFairValueDisclosure_8198772b-afe8-4d76-983f-5c582dcc786e" xlink:href="newt-20241231.xsd#newt_FinancingReceivableFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueNetAssetLiabilityAbstract_bf02a0cf-485f-4729-90dc-7d2dca8bd472" xlink:to="loc_newt_FinancingReceivableFairValueDisclosure_8198772b-afe8-4d76-983f-5c582dcc786e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInFederalHomeLoanBankStockFairValueDisclosure_80dcdd25-9ef1-4655-9d70-0fb4e99a4673" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentInFederalHomeLoanBankStockFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueNetAssetLiabilityAbstract_bf02a0cf-485f-4729-90dc-7d2dca8bd472" xlink:to="loc_us-gaap_InvestmentInFederalHomeLoanBankStockFairValueDisclosure_80dcdd25-9ef1-4655-9d70-0fb4e99a4673" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsFairValueDisclosure_69503639-eb7c-4c4e-b77b-df48c80a5bdb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepositsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueNetAssetLiabilityAbstract_bf02a0cf-485f-4729-90dc-7d2dca8bd472" xlink:to="loc_us-gaap_DepositsFairValueDisclosure_69503639-eb7c-4c4e-b77b-df48c80a5bdb" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_49341124-a822-4efe-bc58-0023e1bf38d1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueNetAssetLiabilityAbstract_bf02a0cf-485f-4729-90dc-7d2dca8bd472" xlink:to="loc_us-gaap_LongTermDebtFairValue_49341124-a822-4efe-bc58-0023e1bf38d1" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/FAIRVALUEMEASUREMENTSLevelIIIRollforwardDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#FAIRVALUEMEASUREMENTSLevelIIIRollforwardDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/FAIRVALUEMEASUREMENTSLevelIIIRollforwardDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_78fa9312-0471-425f-b7a2-1fc423e11376" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_38ec5301-711d-4944-9f9d-4b9128e8570e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_78fa9312-0471-425f-b7a2-1fc423e11376" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_38ec5301-711d-4944-9f9d-4b9128e8570e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_08e94df1-038b-43df-afe7-37ece00a2c77" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByAssetClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_38ec5301-711d-4944-9f9d-4b9128e8570e" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_08e94df1-038b-43df-afe7-37ece00a2c77" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_08e94df1-038b-43df-afe7-37ece00a2c77_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_08e94df1-038b-43df-afe7-37ece00a2c77" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_08e94df1-038b-43df-afe7-37ece00a2c77_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_33e1f462-a312-45f3-8c2b-cfc9e626ade7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_08e94df1-038b-43df-afe7-37ece00a2c77" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_33e1f462-a312-45f3-8c2b-cfc9e626ade7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LoansHeldForInvestmentMember_10bcb175-26fe-4ecb-9107-5e9411e9953f" xlink:href="newt-20241231.xsd#newt_LoansHeldForInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_33e1f462-a312-45f3-8c2b-cfc9e626ade7" xlink:to="loc_newt_LoansHeldForInvestmentMember_10bcb175-26fe-4ecb-9107-5e9411e9953f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LoansHeldForSaleMember_ddc231c7-cc34-4d54-bc46-2ce3725a3fa7" xlink:href="newt-20241231.xsd#newt_LoansHeldForSaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_33e1f462-a312-45f3-8c2b-cfc9e626ade7" xlink:to="loc_newt_LoansHeldForSaleMember_ddc231c7-cc34-4d54-bc46-2ce3725a3fa7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsMember_22de9026-de3e-4096-8b01-609fef812f28" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_33e1f462-a312-45f3-8c2b-cfc9e626ade7" xlink:to="loc_us-gaap_InvestmentsMember_22de9026-de3e-4096-8b01-609fef812f28" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ServicingAssetsMember_6c5476f6-cd21-4d85-8797-298eb114d8b9" xlink:href="newt-20241231.xsd#newt_ServicingAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_33e1f462-a312-45f3-8c2b-cfc9e626ade7" xlink:to="loc_newt_ServicingAssetsMember_6c5476f6-cd21-4d85-8797-298eb114d8b9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_AssetsHeldForSaleMember_361d161e-20b9-4207-acff-32aae98b63a2" xlink:href="newt-20241231.xsd#newt_AssetsHeldForSaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_33e1f462-a312-45f3-8c2b-cfc9e626ade7" xlink:to="loc_newt_AssetsHeldForSaleMember_361d161e-20b9-4207-acff-32aae98b63a2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_1b6f3a71-47e8-4b4b-a71a-9511f30a997d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_33e1f462-a312-45f3-8c2b-cfc9e626ade7" xlink:to="loc_us-gaap_WarrantMember_1b6f3a71-47e8-4b4b-a71a-9511f30a997d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_OtherRealEstateOwnedMember_11bc4931-a474-4b5d-aee8-56f03db7981c" xlink:href="newt-20241231.xsd#newt_OtherRealEstateOwnedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_33e1f462-a312-45f3-8c2b-cfc9e626ade7" xlink:to="loc_newt_OtherRealEstateOwnedMember_11bc4931-a474-4b5d-aee8-56f03db7981c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_2843b5e5-1a8e-46a7-a254-d556ad22f8b5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_38ec5301-711d-4944-9f9d-4b9128e8570e" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_2843b5e5-1a8e-46a7-a254-d556ad22f8b5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_2843b5e5-1a8e-46a7-a254-d556ad22f8b5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_2843b5e5-1a8e-46a7-a254-d556ad22f8b5" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_2843b5e5-1a8e-46a7-a254-d556ad22f8b5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_925226cd-1f31-4659-85fe-226d7055f649" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_2843b5e5-1a8e-46a7-a254-d556ad22f8b5" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_925226cd-1f31-4659-85fe-226d7055f649" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_c2a9cd7b-973f-48e7-9b67-2f1aaede3c2a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentAffiliatedIssuerControlledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_925226cd-1f31-4659-85fe-226d7055f649" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_c2a9cd7b-973f-48e7-9b67-2f1aaede3c2a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember_36aa70cd-88d4-4e16-83ac-671f21fc2da0" xlink:href="newt-20241231.xsd#newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_925226cd-1f31-4659-85fe-226d7055f649" xlink:to="loc_newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember_36aa70cd-88d4-4e16-83ac-671f21fc2da0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_4430b3fd-5067-48a3-a3dc-111e7857a8f7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_38ec5301-711d-4944-9f9d-4b9128e8570e" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_4430b3fd-5067-48a3-a3dc-111e7857a8f7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_4430b3fd-5067-48a3-a3dc-111e7857a8f7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_4430b3fd-5067-48a3-a3dc-111e7857a8f7" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_4430b3fd-5067-48a3-a3dc-111e7857a8f7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_f2b7f934-51ae-466e-9552-d64fa334a365" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_4430b3fd-5067-48a3-a3dc-111e7857a8f7" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_f2b7f934-51ae-466e-9552-d64fa334a365" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtAndEquitySecuritiesUnrealizedGainLossMember_01eae572-464a-4030-8e97-a84d938f03f7" xlink:href="newt-20241231.xsd#newt_DebtAndEquitySecuritiesUnrealizedGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_f2b7f934-51ae-466e-9552-d64fa334a365" xlink:to="loc_newt_DebtAndEquitySecuritiesUnrealizedGainLossMember_01eae572-464a-4030-8e97-a84d938f03f7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtAndEquitySecuritiesRealizedGainLossMember_99fa3ed0-4cc9-4db6-82a0-69ec2a8f29f1" xlink:href="newt-20241231.xsd#newt_DebtAndEquitySecuritiesRealizedGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_f2b7f934-51ae-466e-9552-d64fa334a365" xlink:to="loc_newt_DebtAndEquitySecuritiesRealizedGainLossMember_99fa3ed0-4cc9-4db6-82a0-69ec2a8f29f1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NatureOfGainLossAxis_d1c4db57-dd8f-4ac1-ba43-2e476dae3cca" xlink:href="newt-20241231.xsd#newt_NatureOfGainLossAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_38ec5301-711d-4944-9f9d-4b9128e8570e" xlink:to="loc_newt_NatureOfGainLossAxis_d1c4db57-dd8f-4ac1-ba43-2e476dae3cca" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NatureOfGainLossAxisDomain_d1c4db57-dd8f-4ac1-ba43-2e476dae3cca_default" xlink:href="newt-20241231.xsd#newt_NatureOfGainLossAxisDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_newt_NatureOfGainLossAxis_d1c4db57-dd8f-4ac1-ba43-2e476dae3cca" xlink:to="loc_newt_NatureOfGainLossAxisDomain_d1c4db57-dd8f-4ac1-ba43-2e476dae3cca_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NatureOfGainLossAxisDomain_b109f3a2-9592-4f2d-a1c8-2d5ef0af7e0a" xlink:href="newt-20241231.xsd#newt_NatureOfGainLossAxisDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_newt_NatureOfGainLossAxis_d1c4db57-dd8f-4ac1-ba43-2e476dae3cca" xlink:to="loc_newt_NatureOfGainLossAxisDomain_b109f3a2-9592-4f2d-a1c8-2d5ef0af7e0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ChangesInValuationInputsOrAdjustmentsMember_dbfb8b58-d1a0-431e-8cc6-bde9448eecca" xlink:href="newt-20241231.xsd#newt_ChangesInValuationInputsOrAdjustmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_NatureOfGainLossAxisDomain_b109f3a2-9592-4f2d-a1c8-2d5ef0af7e0a" xlink:to="loc_newt_ChangesInValuationInputsOrAdjustmentsMember_dbfb8b58-d1a0-431e-8cc6-bde9448eecca" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FactorsOtherThanChangesInValuationInputsOrAdjustmentsMember_82c40cf2-db49-4bc1-a55c-df1a3cbb4c1e" xlink:href="newt-20241231.xsd#newt_FactorsOtherThanChangesInValuationInputsOrAdjustmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_NatureOfGainLossAxisDomain_b109f3a2-9592-4f2d-a1c8-2d5ef0af7e0a" xlink:to="loc_newt_FactorsOtherThanChangesInValuationInputsOrAdjustmentsMember_82c40cf2-db49-4bc1-a55c-df1a3cbb4c1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_bb52b60d-49c9-416e-aec5-ab3c0ebd0485" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_38ec5301-711d-4944-9f9d-4b9128e8570e" xlink:to="loc_us-gaap_FinancialInstrumentAxis_bb52b60d-49c9-416e-aec5-ab3c0ebd0485" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_bb52b60d-49c9-416e-aec5-ab3c0ebd0485_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_bb52b60d-49c9-416e-aec5-ab3c0ebd0485" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_bb52b60d-49c9-416e-aec5-ab3c0ebd0485_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0e39e3a2-c267-406e-b032-2bdb45654139" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_bb52b60d-49c9-416e-aec5-ab3c0ebd0485" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0e39e3a2-c267-406e-b032-2bdb45654139" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanMember_96b79430-7e69-4098-be41-658a9ed0b6aa" xlink:href="newt-20241231.xsd#newt_SBA7aLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0e39e3a2-c267-406e-b032-2bdb45654139" xlink:to="loc_newt_SBA7aLoanMember_96b79430-7e69-4098-be41-658a9ed0b6aa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ConventionalLoansMember_4f58ec5e-89ae-4502-bca4-37e1b29c083f" xlink:href="newt-20241231.xsd#newt_ConventionalLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0e39e3a2-c267-406e-b032-2bdb45654139" xlink:to="loc_newt_ConventionalLoansMember_4f58ec5e-89ae-4502-bca4-37e1b29c083f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_MortgageLoanMember_205f30ce-9168-48ea-bcc7-d575e8f9b9bf" xlink:href="newt-20241231.xsd#newt_MortgageLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0e39e3a2-c267-406e-b032-2bdb45654139" xlink:to="loc_newt_MortgageLoanMember_205f30ce-9168-48ea-bcc7-d575e8f9b9bf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_78fa9312-0471-425f-b7a2-1fc423e11376" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_1ed1a9ac-0790-4af1-a7d2-76284722be0e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_1ed1a9ac-0790-4af1-a7d2-76284722be0e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValueAfterConversion_8c9626d4-e695-43f9-ad3a-4be6ad140f2b" xlink:href="newt-20241231.xsd#newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValueAfterConversion"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:to="loc_newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValueAfterConversion_8c9626d4-e695-43f9-ad3a-4be6ad140f2b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetReclassificationOfLoansFairValueAndLowerOfCostOrMarket_b7a3a7e7-562b-42a8-93a9-acf1595949ce" xlink:href="newt-20241231.xsd#newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetReclassificationOfLoansFairValueAndLowerOfCostOrMarket"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:to="loc_newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetReclassificationOfLoansFairValueAndLowerOfCostOrMarket_b7a3a7e7-562b-42a8-93a9-acf1595949ce" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetReclassificationOfLoansHeldForSaleAndHeldForInvestment_159da3bd-5c9f-4be2-b7df-81aaa117a674" xlink:href="newt-20241231.xsd#newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetReclassificationOfLoansHeldForSaleAndHeldForInvestment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:to="loc_newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetReclassificationOfLoansHeldForSaleAndHeldForInvestment_159da3bd-5c9f-4be2-b7df-81aaa117a674" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_04ba1756-5ae4-44b3-bb46-3870587feb34" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_04ba1756-5ae4-44b3-bb46-3870587feb34" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_d40ddff3-1d61-4873-8506-246a6c3cc635" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_d40ddff3-1d61-4873-8506-246a6c3cc635" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesFromOtherAssetClass_69de066c-9a38-449f-aee2-5ae0a3438a8a" xlink:href="newt-20241231.xsd#newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesFromOtherAssetClass"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:to="loc_newt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesFromOtherAssetClass_69de066c-9a38-449f-aee2-5ae0a3438a8a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_80091e31-223f-447c-95d1-c360b29817cb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_80091e31-223f-447c-95d1-c360b29817cb" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_66af4615-d5d0-4987-a6a0-e3a7b295cb3b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_66af4615-d5d0-4987-a6a0-e3a7b295cb3b" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues_087e7bd7-a3e1-41aa-9997-44f4b8e9f6a0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_eebcf255-3558-4950-9540-946349acd4ae" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues_087e7bd7-a3e1-41aa-9997-44f4b8e9f6a0" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_4cc21e85-1b9d-4af3-8edc-909310918e80" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList_c7f39dc4-775e-4932-85db-d9164457e592" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_78fa9312-0471-425f-b7a2-1fc423e11376" xlink:to="loc_us-gaap_FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList_c7f39dc4-775e-4932-85db-d9164457e592" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/FAIRVALUEMEASUREMENTSUnobservableUnitsDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#FAIRVALUEMEASUREMENTSUnobservableUnitsDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/FAIRVALUEMEASUREMENTSUnobservableUnitsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_33070b83-a333-4831-92d1-4de21d7ce548" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_33070b83-a333-4831-92d1-4de21d7ce548" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_a992224f-0878-4836-8d65-e3ab2eac52ad" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_33070b83-a333-4831-92d1-4de21d7ce548" xlink:to="loc_srt_RangeAxis_a992224f-0878-4836-8d65-e3ab2eac52ad" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_a992224f-0878-4836-8d65-e3ab2eac52ad_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_a992224f-0878-4836-8d65-e3ab2eac52ad" xlink:to="loc_srt_RangeMember_a992224f-0878-4836-8d65-e3ab2eac52ad_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_2622242c-ad80-49dd-b47d-afb63eaa1dc2" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_a992224f-0878-4836-8d65-e3ab2eac52ad" xlink:to="loc_srt_RangeMember_2622242c-ad80-49dd-b47d-afb63eaa1dc2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_WeightedAverageMember_7299d0ab-230c-4595-93d0-e124573db178" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_WeightedAverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_2622242c-ad80-49dd-b47d-afb63eaa1dc2" xlink:to="loc_srt_WeightedAverageMember_7299d0ab-230c-4595-93d0-e124573db178" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_0b4639d8-1088-459c-a02d-aa18f1994890" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_2622242c-ad80-49dd-b47d-afb63eaa1dc2" xlink:to="loc_srt_MinimumMember_0b4639d8-1088-459c-a02d-aa18f1994890" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_74ca3892-dfa3-4cce-91d8-e6cb17a3046a" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_2622242c-ad80-49dd-b47d-afb63eaa1dc2" xlink:to="loc_srt_MaximumMember_74ca3892-dfa3-4cce-91d8-e6cb17a3046a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_e98c7f3c-e74b-4b3d-a181-6f27694d5719" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_33070b83-a333-4831-92d1-4de21d7ce548" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_e98c7f3c-e74b-4b3d-a181-6f27694d5719" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_e98c7f3c-e74b-4b3d-a181-6f27694d5719_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_e98c7f3c-e74b-4b3d-a181-6f27694d5719" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_e98c7f3c-e74b-4b3d-a181-6f27694d5719_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_e98c7f3c-e74b-4b3d-a181-6f27694d5719" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_MeasurementInputMarketYieldsMember_dfe7fb38-b4c2-4ba9-b29a-6c4543b32325" xlink:href="newt-20241231.xsd#newt_MeasurementInputMarketYieldsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:to="loc_newt_MeasurementInputMarketYieldsMember_dfe7fb38-b4c2-4ba9-b29a-6c4543b32325" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputPrepaymentRateMember_7dfe0930-116d-44b7-b1a2-9a3d9fcf6bbd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputPrepaymentRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:to="loc_us-gaap_MeasurementInputPrepaymentRateMember_7dfe0930-116d-44b7-b1a2-9a3d9fcf6bbd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputDefaultRateMember_8604052c-c1fb-4411-a667-c12df0d3c37e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputDefaultRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:to="loc_us-gaap_MeasurementInputDefaultRateMember_8604052c-c1fb-4411-a667-c12df0d3c37e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_MeasurementInputCostMember_06991493-1e36-412e-b666-8d2030ad647b" xlink:href="newt-20241231.xsd#newt_MeasurementInputCostMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:to="loc_newt_MeasurementInputCostMember_06991493-1e36-412e-b666-8d2030ad647b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_MeasurementInputWeightedAverageCostOfCapitalMember_e471e8ac-0b71-497d-b414-d2956ec00ea4" xlink:href="newt-20241231.xsd#newt_MeasurementInputWeightedAverageCostOfCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:to="loc_newt_MeasurementInputWeightedAverageCostOfCapitalMember_e471e8ac-0b71-497d-b414-d2956ec00ea4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_MeasurementInputPresentValueFactorMember_81555df2-3b86-40d7-8282-aab7057146cb" xlink:href="newt-20241231.xsd#newt_MeasurementInputPresentValueFactorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:to="loc_newt_MeasurementInputPresentValueFactorMember_81555df2-3b86-40d7-8282-aab7057146cb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputDiscountRateMember_597f94ba-7c8c-41ed-bbe2-c9cd8bd8f573" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputDiscountRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:to="loc_us-gaap_MeasurementInputDiscountRateMember_597f94ba-7c8c-41ed-bbe2-c9cd8bd8f573" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputPriceVolatilityMember_6729e935-4876-4079-80d1-4d73e6dd5f8b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputPriceVolatilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:to="loc_us-gaap_MeasurementInputPriceVolatilityMember_6729e935-4876-4079-80d1-4d73e6dd5f8b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_MeasurementInputDividendYieldMember_bb8e7c9a-4887-4ce1-a3f1-3b047a4ac2a3" xlink:href="newt-20241231.xsd#newt_MeasurementInputDividendYieldMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:to="loc_newt_MeasurementInputDividendYieldMember_bb8e7c9a-4887-4ce1-a3f1-3b047a4ac2a3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputRiskFreeInterestRateMember_5801fb96-5e7f-45d8-ac5f-3be575dfa64a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputRiskFreeInterestRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_45ccc0ae-8780-4c9b-9b5f-90720f551b5c" xlink:to="loc_us-gaap_MeasurementInputRiskFreeInterestRateMember_5801fb96-5e7f-45d8-ac5f-3be575dfa64a" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_550a1a11-c7fe-46ab-8533-47d304ef5939" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_33070b83-a333-4831-92d1-4de21d7ce548" xlink:to="loc_us-gaap_FinancialInstrumentAxis_550a1a11-c7fe-46ab-8533-47d304ef5939" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_550a1a11-c7fe-46ab-8533-47d304ef5939_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_550a1a11-c7fe-46ab-8533-47d304ef5939" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_550a1a11-c7fe-46ab-8533-47d304ef5939_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_39337422-ee6d-46c1-a48d-e49685df6c0d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_550a1a11-c7fe-46ab-8533-47d304ef5939" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_39337422-ee6d-46c1-a48d-e49685df6c0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_UnguaranteedAccrualInvestmentsMember_44805041-0386-44dd-a9d2-f2b2f20166ae" xlink:href="newt-20241231.xsd#newt_UnguaranteedAccrualInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_39337422-ee6d-46c1-a48d-e49685df6c0d" xlink:to="loc_newt_UnguaranteedAccrualInvestmentsMember_44805041-0386-44dd-a9d2-f2b2f20166ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_UnguaranteedNonAccrualInvestmentsMember_1ef3faee-8fac-48ce-80ab-be7d39dce97d" xlink:href="newt-20241231.xsd#newt_UnguaranteedNonAccrualInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_39337422-ee6d-46c1-a48d-e49685df6c0d" xlink:to="loc_newt_UnguaranteedNonAccrualInvestmentsMember_1ef3faee-8fac-48ce-80ab-be7d39dce97d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LoansHeldForSaleMember_025a602f-aa7e-4c76-8589-ab51468c16f1" xlink:href="newt-20241231.xsd#newt_LoansHeldForSaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_39337422-ee6d-46c1-a48d-e49685df6c0d" xlink:to="loc_newt_LoansHeldForSaleMember_025a602f-aa7e-4c76-8589-ab51468c16f1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsMember_b3266a17-2d0b-4da4-be37-a0f4db3f2869" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_39337422-ee6d-46c1-a48d-e49685df6c0d" xlink:to="loc_us-gaap_InvestmentsMember_b3266a17-2d0b-4da4-be37-a0f4db3f2869" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_0233bd83-8a21-45e9-9e7f-8b511f8cbfb1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_33070b83-a333-4831-92d1-4de21d7ce548" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_0233bd83-8a21-45e9-9e7f-8b511f8cbfb1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_0233bd83-8a21-45e9-9e7f-8b511f8cbfb1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_0233bd83-8a21-45e9-9e7f-8b511f8cbfb1" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_0233bd83-8a21-45e9-9e7f-8b511f8cbfb1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_076e6f3c-de88-455f-b7b7-68d298ebc023" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_0233bd83-8a21-45e9-9e7f-8b511f8cbfb1" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_076e6f3c-de88-455f-b7b7-68d298ebc023" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_3007cf4d-4240-4c66-970f-52063bd50f0a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentUnaffiliatedIssuerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_076e6f3c-de88-455f-b7b7-68d298ebc023" xlink:to="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_3007cf4d-4240-4c66-970f-52063bd50f0a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember_908a0350-153d-449d-ae7e-b0c2a5ccef62" xlink:href="newt-20241231.xsd#newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_076e6f3c-de88-455f-b7b7-68d298ebc023" xlink:to="loc_newt_InvestmentAffiliatedIssuerControlledNotMajorityOwnedAndNoncontrolledMember_908a0350-153d-449d-ae7e-b0c2a5ccef62" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherControlledCompaniesMember_0bfdde2d-f251-46ad-a2e1-4eb02ff58841" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherControlledCompaniesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_076e6f3c-de88-455f-b7b7-68d298ebc023" xlink:to="loc_us-gaap_OtherControlledCompaniesMember_0bfdde2d-f251-46ad-a2e1-4eb02ff58841" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_332dedcf-1cb2-410c-a76e-c91ad6e6131f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_076e6f3c-de88-455f-b7b7-68d298ebc023" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_332dedcf-1cb2-410c-a76e-c91ad6e6131f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_fe0d8584-f840-4978-b239-6bee78c36b2f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_33070b83-a333-4831-92d1-4de21d7ce548" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_fe0d8584-f840-4978-b239-6bee78c36b2f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_fe0d8584-f840-4978-b239-6bee78c36b2f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_fe0d8584-f840-4978-b239-6bee78c36b2f" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_fe0d8584-f840-4978-b239-6bee78c36b2f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_907f4349-f6d1-4837-9321-b0502e18b7fe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_fe0d8584-f840-4978-b239-6bee78c36b2f" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_907f4349-f6d1-4837-9321-b0502e18b7fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_578243cd-fdc2-4a37-a46e-e6b768fecaf2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_907f4349-f6d1-4837-9321-b0502e18b7fe" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_578243cd-fdc2-4a37-a46e-e6b768fecaf2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis_99fa7ef3-fd18-42dd-94e7-babe286bdcbe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_33070b83-a333-4831-92d1-4de21d7ce548" xlink:to="loc_us-gaap_ValuationTechniqueAxis_99fa7ef3-fd18-42dd-94e7-babe286bdcbe" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_99fa7ef3-fd18-42dd-94e7-babe286bdcbe_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationTechniqueAxis_99fa7ef3-fd18-42dd-94e7-babe286bdcbe" xlink:to="loc_us-gaap_ValuationTechniqueDomain_99fa7ef3-fd18-42dd-94e7-babe286bdcbe_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_3fdd3f2b-252c-4378-9732-d039de21f2de" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationTechniqueAxis_99fa7ef3-fd18-42dd-94e7-babe286bdcbe" xlink:to="loc_us-gaap_ValuationTechniqueDomain_3fdd3f2b-252c-4378-9732-d039de21f2de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FairValueMember_93932648-5247-44b9-8236-4b8bb3d3e544" xlink:href="newt-20241231.xsd#newt_FairValueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_3fdd3f2b-252c-4378-9732-d039de21f2de" xlink:to="loc_newt_FairValueMember_93932648-5247-44b9-8236-4b8bb3d3e544" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LowerOfCostOrMarketMember_3620fdc1-115b-4190-81bc-08b59deed950" xlink:href="newt-20241231.xsd#newt_LowerOfCostOrMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_3fdd3f2b-252c-4378-9732-d039de21f2de" xlink:to="loc_newt_LowerOfCostOrMarketMember_3620fdc1-115b-4190-81bc-08b59deed950" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_9d6cf313-b122-4b55-aa4e-855d1c817993" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_9d6cf313-b122-4b55-aa4e-855d1c817993" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_InvestmentOwnedFairValueMeasurementInput_b7325574-9d68-477f-9ac8-1629181428ed" xlink:href="newt-20241231.xsd#newt_InvestmentOwnedFairValueMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_newt_InvestmentOwnedFairValueMeasurementInput_b7325574-9d68-477f-9ac8-1629181428ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetAtFairValueAmount_d9b6791d-34b3-41dd-b921-eadf9a5293c3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetAtFairValueAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_us-gaap_ServicingAssetAtFairValueAmount_d9b6791d-34b3-41dd-b921-eadf9a5293c3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetMeasurementInput_255eef6d-74e6-41eb-9dbf-258dcff8fec9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAssetMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_us-gaap_ServicingAssetMeasurementInput_255eef6d-74e6-41eb-9dbf-258dcff8fec9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure_77cd9467-33ee-420e-baaa-0c392ff41d4b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure_77cd9467-33ee-420e-baaa-0c392ff41d4b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LongLivedAssetHeldForSaleMeasurementInput_c5911ecf-5306-4383-85df-e97a00cb2175" xlink:href="newt-20241231.xsd#newt_LongLivedAssetHeldForSaleMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_newt_LongLivedAssetHeldForSaleMeasurementInput_c5911ecf-5306-4383-85df-e97a00cb2175" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherRealEstate_2091bbe7-88b6-41fa-a254-75b164c5c8a8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_us-gaap_OtherRealEstate_2091bbe7-88b6-41fa-a254-75b164c5c8a8" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantsAndRightsOutstanding_62d136eb-5832-479f-8b57-2cfb7b835203" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_WarrantsAndRightsOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_us-gaap_WarrantsAndRightsOutstanding_62d136eb-5832-479f-8b57-2cfb7b835203" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantsAndRightsOutstandingMeasurementInput_844682e5-011d-43cf-9bf0-03a394eaf71b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_WarrantsAndRightsOutstandingMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_us-gaap_WarrantsAndRightsOutstandingMeasurementInput_844682e5-011d-43cf-9bf0-03a394eaf71b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAsset_1a2d9f62-3b1c-4ecc-8ae2-5c1e29f6eea1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ServicingAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_2c419745-7a5d-4258-8d1a-3f6dfe1b54c8" xlink:to="loc_us-gaap_ServicingAsset_1a2d9f62-3b1c-4ecc-8ae2-5c1e29f6eea1" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/FAIRVALUEMEASUREMENTSFairValueofDebtDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#FAIRVALUEMEASUREMENTSFairValueofDebtDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/FAIRVALUEMEASUREMENTSFairValueofDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_f19276d2-0732-471c-a25f-4e7bc031a7f3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_81b93ab6-91dc-4b95-9b57-8c4441f5cbf9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f19276d2-0732-471c-a25f-4e7bc031a7f3" xlink:to="loc_us-gaap_DebtInstrumentTable_81b93ab6-91dc-4b95-9b57-8c4441f5cbf9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_020de620-d768-4ef2-bf3d-f916a20724d9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_81b93ab6-91dc-4b95-9b57-8c4441f5cbf9" xlink:to="loc_us-gaap_DebtInstrumentAxis_020de620-d768-4ef2-bf3d-f916a20724d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_020de620-d768-4ef2-bf3d-f916a20724d9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_020de620-d768-4ef2-bf3d-f916a20724d9" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_020de620-d768-4ef2-bf3d-f916a20724d9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_020de620-d768-4ef2-bf3d-f916a20724d9" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2024NotesMember_24289e15-0f00-4e66-bc72-4681d9408fd7" xlink:href="newt-20241231.xsd#newt_A2024NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:to="loc_newt_A2024NotesMember_24289e15-0f00-4e66-bc72-4681d9408fd7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2026NotesMember_89871ab6-a4ff-453b-a514-54298d40b069" xlink:href="newt-20241231.xsd#newt_A2026NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:to="loc_newt_A2026NotesMember_89871ab6-a4ff-453b-a514-54298d40b069" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2028NotesMember_ddd6fae8-65e1-4a59-887d-fa78973f2dfe" xlink:href="newt-20241231.xsd#newt_A2028NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:to="loc_newt_A2028NotesMember_ddd6fae8-65e1-4a59-887d-fa78973f2dfe" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.50NotesMember_d67910af-fe88-41a3-9ea3-da30f8f91aa3" xlink:href="newt-20241231.xsd#newt_A20298.50NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:to="loc_newt_A20298.50NotesMember_d67910af-fe88-41a3-9ea3-da30f8f91aa3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.625NotesMember_a63aa7e8-54d8-4612-a489-9182e0369c0a" xlink:href="newt-20241231.xsd#newt_A20298.625NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:to="loc_newt_A20298.625NotesMember_a63aa7e8-54d8-4612-a489-9182e0369c0a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PrivateParentCompanyNotesMember_b4157ca6-a573-4120-be1b-e71dfeb71e63" xlink:href="newt-20241231.xsd#newt_PrivateParentCompanyNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:to="loc_newt_PrivateParentCompanyNotesMember_b4157ca6-a573-4120-be1b-e71dfeb71e63" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SecuritizationTrustsMember_eef2d58b-bfdd-4e91-9b23-e50a80f3e063" xlink:href="newt-20241231.xsd#newt_SecuritizationTrustsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:to="loc_newt_SecuritizationTrustsMember_eef2d58b-bfdd-4e91-9b23-e50a80f3e063" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FHLBBorrowingsMember_96168dc9-f668-4ee5-8728-0058b7eef1e1" xlink:href="newt-20241231.xsd#newt_FHLBBorrowingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:to="loc_newt_FHLBBorrowingsMember_96168dc9-f668-4ee5-8728-0058b7eef1e1" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BankBorrowingsMember_deeb1ce8-0360-46f4-a9ec-8dfb6e72d854" xlink:href="newt-20241231.xsd#newt_BankBorrowingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a657a6b-1c59-4d9c-9ae4-028bd9e9d46a" xlink:to="loc_newt_BankBorrowingsMember_deeb1ce8-0360-46f4-a9ec-8dfb6e72d854" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_050c2d73-07c4-4190-a93d-d080121f8b0a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_81b93ab6-91dc-4b95-9b57-8c4441f5cbf9" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_050c2d73-07c4-4190-a93d-d080121f8b0a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_050c2d73-07c4-4190-a93d-d080121f8b0a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_050c2d73-07c4-4190-a93d-d080121f8b0a" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_050c2d73-07c4-4190-a93d-d080121f8b0a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_0e450c54-8734-4094-b2d0-3ad04bfbb108" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_050c2d73-07c4-4190-a93d-d080121f8b0a" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_0e450c54-8734-4094-b2d0-3ad04bfbb108" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MediumTermNotesMember_4e43e80c-8bec-43c3-92ce-14e30fecd0aa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MediumTermNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_0e450c54-8734-4094-b2d0-3ad04bfbb108" xlink:to="loc_us-gaap_MediumTermNotesMember_4e43e80c-8bec-43c3-92ce-14e30fecd0aa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_1b92c956-7bad-4544-b25c-e64a6d915b72" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_81b93ab6-91dc-4b95-9b57-8c4441f5cbf9" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_1b92c956-7bad-4544-b25c-e64a6d915b72" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_1b92c956-7bad-4544-b25c-e64a6d915b72_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_1b92c956-7bad-4544-b25c-e64a6d915b72" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_1b92c956-7bad-4544-b25c-e64a6d915b72_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_33f7d6d4-c711-4e55-890a-4ce4f09a5027" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_1b92c956-7bad-4544-b25c-e64a6d915b72" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_33f7d6d4-c711-4e55-890a-4ce4f09a5027" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputSharePriceMember_afca488c-212e-4f72-8631-0c20abb59877" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputSharePriceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_33f7d6d4-c711-4e55-890a-4ce4f09a5027" xlink:to="loc_us-gaap_MeasurementInputSharePriceMember_afca488c-212e-4f72-8631-0c20abb59877" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4113acda-426d-4eb2-9adb-af358f7c4b63" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_81b93ab6-91dc-4b95-9b57-8c4441f5cbf9" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4113acda-426d-4eb2-9adb-af358f7c4b63" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_4113acda-426d-4eb2-9adb-af358f7c4b63_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4113acda-426d-4eb2-9adb-af358f7c4b63" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_4113acda-426d-4eb2-9adb-af358f7c4b63_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_3392acc1-3458-46d7-9b5b-6cb6e6fd8e00" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4113acda-426d-4eb2-9adb-af358f7c4b63" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_3392acc1-3458-46d7-9b5b-6cb6e6fd8e00" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_91115208-1aff-4896-8aec-132615aad499" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_3392acc1-3458-46d7-9b5b-6cb6e6fd8e00" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_91115208-1aff-4896-8aec-132615aad499" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_cd0ea311-40b5-4aa3-9576-b42c0ea83224" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_3392acc1-3458-46d7-9b5b-6cb6e6fd8e00" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_cd0ea311-40b5-4aa3-9576-b42c0ea83224" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMeasurementInput_a0ca9212-5f6d-443b-b43f-20212fb9737c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f19276d2-0732-471c-a25f-4e7bc031a7f3" xlink:to="loc_us-gaap_LongTermDebtMeasurementInput_a0ca9212-5f6d-443b-b43f-20212fb9737c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_e21e36c8-cb89-44f3-a358-1689666dcd9f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f19276d2-0732-471c-a25f-4e7bc031a7f3" xlink:to="loc_us-gaap_LongTermDebtFairValue_e21e36c8-cb89-44f3-a358-1689666dcd9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_bb958709-52ec-4813-a94b-927916948fd4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtWeightedAverageInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f19276d2-0732-471c-a25f-4e7bc031a7f3" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_bb958709-52ec-4813-a94b-927916948fd4" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/DEPOSITSNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#DEPOSITSNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/DEPOSITSNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositLiabilityLineItems_28b3bc89-6ddb-419b-b56d-03496ba4d27b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepositLiabilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositsTable_c9ab7bb1-5fc1-4a35-b53a-e4f682ba5a8f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DepositLiabilityLineItems_28b3bc89-6ddb-419b-b56d-03496ba4d27b" xlink:to="loc_us-gaap_TimeDepositsTable_c9ab7bb1-5fc1-4a35-b53a-e4f682ba5a8f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByLiabilityClassAxis_e118b4fd-015f-4ffd-b158-3aba140ef052" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByLiabilityClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TimeDepositsTable_c9ab7bb1-5fc1-4a35-b53a-e4f682ba5a8f" xlink:to="loc_us-gaap_FairValueByLiabilityClassAxis_e118b4fd-015f-4ffd-b158-3aba140ef052" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_e118b4fd-015f-4ffd-b158-3aba140ef052_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_e118b4fd-015f-4ffd-b158-3aba140ef052" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_e118b4fd-015f-4ffd-b158-3aba140ef052_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_1fa77c14-19a6-4522-b3d7-c9e3dec79d86" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_e118b4fd-015f-4ffd-b158-3aba140ef052" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_1fa77c14-19a6-4522-b3d7-c9e3dec79d86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CertificatesOfDepositMember_9da6f27c-f325-4681-a19c-bbf8bacbdfc8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CertificatesOfDepositMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_1fa77c14-19a6-4522-b3d7-c9e3dec79d86" xlink:to="loc_us-gaap_CertificatesOfDepositMember_9da6f27c-f325-4681-a19c-bbf8bacbdfc8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit_e999cbbb-7032-4e56-a8f7-ff08dc53ca5e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DepositLiabilityLineItems_28b3bc89-6ddb-419b-b56d-03496ba4d27b" xlink:to="loc_us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit_e999cbbb-7032-4e56-a8f7-ff08dc53ca5e" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BORROWINGSLongtermDebtDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BORROWINGSLongtermDebtDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BORROWINGSLongtermDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_fe17a7a5-4939-47f8-bbe6-4e05618990b9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_5b31b4db-8062-40f1-8d72-285704c685b7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_fe17a7a5-4939-47f8-bbe6-4e05618990b9" xlink:to="loc_us-gaap_DebtInstrumentTable_5b31b4db-8062-40f1-8d72-285704c685b7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_69f791ae-ba5e-4975-b021-d7020dbbff38" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_5b31b4db-8062-40f1-8d72-285704c685b7" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_69f791ae-ba5e-4975-b021-d7020dbbff38" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_69f791ae-ba5e-4975-b021-d7020dbbff38_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_69f791ae-ba5e-4975-b021-d7020dbbff38" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_69f791ae-ba5e-4975-b021-d7020dbbff38_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_98764f91-485b-4440-8e28-fbe8cd3ec240" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_69f791ae-ba5e-4975-b021-d7020dbbff38" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_98764f91-485b-4440-8e28-fbe8cd3ec240" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_cfaed524-eb8d-481c-84b8-59d62525f7e1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_98764f91-485b-4440-8e28-fbe8cd3ec240" xlink:to="loc_us-gaap_LineOfCreditMember_cfaed524-eb8d-481c-84b8-59d62525f7e1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_801fb0a7-7e06-48af-9f9b-ba50f0ac1976" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_98764f91-485b-4440-8e28-fbe8cd3ec240" xlink:to="loc_us-gaap_SecuredDebtMember_801fb0a7-7e06-48af-9f9b-ba50f0ac1976" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MediumTermNotesMember_1070edbe-7da9-4272-8f3b-4f0092a8e408" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MediumTermNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_98764f91-485b-4440-8e28-fbe8cd3ec240" xlink:to="loc_us-gaap_MediumTermNotesMember_1070edbe-7da9-4272-8f3b-4f0092a8e408" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_b5554e6d-9395-4b48-b07f-dc617ab86e90" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_5b31b4db-8062-40f1-8d72-285704c685b7" xlink:to="loc_us-gaap_DebtInstrumentAxis_b5554e6d-9395-4b48-b07f-dc617ab86e90" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_b5554e6d-9395-4b48-b07f-dc617ab86e90_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_b5554e6d-9395-4b48-b07f-dc617ab86e90" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_b5554e6d-9395-4b48-b07f-dc617ab86e90_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_b5554e6d-9395-4b48-b07f-dc617ab86e90" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_WebsterNMSNoteMember_1b6513c1-b14b-4237-b2d2-87296952997c" xlink:href="newt-20241231.xsd#newt_WebsterNMSNoteMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_WebsterNMSNoteMember_1b6513c1-b14b-4237-b2d2-87296952997c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CapitalOneFacilitiesMember_8972f4b5-c875-4624-a1b8-2852ab71ee2e" xlink:href="newt-20241231.xsd#newt_CapitalOneFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_CapitalOneFacilitiesMember_8972f4b5-c875-4624-a1b8-2852ab71ee2e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SPVIIDeutscheBankFacilityMember_ca90f319-fd28-4936-934d-85ea754a5090" xlink:href="newt-20241231.xsd#newt_SPVIIDeutscheBankFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_SPVIIDeutscheBankFacilityMember_ca90f319-fd28-4936-934d-85ea754a5090" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SPVIIIOneFloridaBankFacilityMember_4b95ed6f-3999-4c40-b6a8-49e8c11af3be" xlink:href="newt-20241231.xsd#newt_SPVIIIOneFloridaBankFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_SPVIIIOneFloridaBankFacilityMember_4b95ed6f-3999-4c40-b6a8-49e8c11af3be" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankAdvancesMember_50f16bd8-72cb-459a-96c9-01d4f7c136ae" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FederalHomeLoanBankAdvancesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_us-gaap_FederalHomeLoanBankAdvancesMember_50f16bd8-72cb-459a-96c9-01d4f7c136ae" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2024NotesMember_963be3dd-3cc9-4d3c-a593-4fe53cd0bff7" xlink:href="newt-20241231.xsd#newt_A2024NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_A2024NotesMember_963be3dd-3cc9-4d3c-a593-4fe53cd0bff7" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2025500NotesMember_91d7718c-6633-4b6f-8c6e-e203b157e61d" xlink:href="newt-20241231.xsd#newt_A2025500NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_A2025500NotesMember_91d7718c-6633-4b6f-8c6e-e203b157e61d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20258125NotesMember_2d09ab57-4eb6-4400-a513-2bf49af1018f" xlink:href="newt-20241231.xsd#newt_A20258125NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_A20258125NotesMember_2d09ab57-4eb6-4400-a513-2bf49af1018f" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2026NotesMember_052764ca-ad0c-4686-8964-a00d3c0256d3" xlink:href="newt-20241231.xsd#newt_A2026NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_A2026NotesMember_052764ca-ad0c-4686-8964-a00d3c0256d3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2027NotesMember_58d32b49-f0ce-4fbc-a327-30c768aba77e" xlink:href="newt-20241231.xsd#newt_A2027NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_A2027NotesMember_58d32b49-f0ce-4fbc-a327-30c768aba77e" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2028NotesMember_5526daff-6214-40f6-9329-3d4170a423b6" xlink:href="newt-20241231.xsd#newt_A2028NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_A2028NotesMember_5526daff-6214-40f6-9329-3d4170a423b6" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.50NotesMember_76b6f8b6-a843-4dea-aa35-b76e5180bf03" xlink:href="newt-20241231.xsd#newt_A20298.50NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_A20298.50NotesMember_76b6f8b6-a843-4dea-aa35-b76e5180bf03" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.625NotesMember_48aa254d-dd06-4f81-b88e-5375d271a475" xlink:href="newt-20241231.xsd#newt_A20298.625NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_A20298.625NotesMember_48aa254d-dd06-4f81-b88e-5375d271a475" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SecuritizationTrustsMember_11dca4f7-983f-4936-9204-442a9a87f655" xlink:href="newt-20241231.xsd#newt_SecuritizationTrustsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6bdda925-f718-415a-a213-8bf88458dfa4" xlink:to="loc_newt_SecuritizationTrustsMember_11dca4f7-983f-4936-9204-442a9a87f655" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_2217cc21-6070-4900-b429-4ec1857d88fe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_5b31b4db-8062-40f1-8d72-285704c685b7" xlink:to="loc_us-gaap_CreditFacilityAxis_2217cc21-6070-4900-b429-4ec1857d88fe" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_2217cc21-6070-4900-b429-4ec1857d88fe_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_2217cc21-6070-4900-b429-4ec1857d88fe" xlink:to="loc_us-gaap_CreditFacilityDomain_2217cc21-6070-4900-b429-4ec1857d88fe_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_22587f1b-608a-4b11-a9fd-34fa491d9f89" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_2217cc21-6070-4900-b429-4ec1857d88fe" xlink:to="loc_us-gaap_CreditFacilityDomain_22587f1b-608a-4b11-a9fd-34fa491d9f89" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CapitalOneSP1Member_dd0a6a04-e9dc-4b30-a920-6bb228243ab2" xlink:href="newt-20241231.xsd#newt_CapitalOneSP1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_22587f1b-608a-4b11-a9fd-34fa491d9f89" xlink:to="loc_newt_CapitalOneSP1Member_dd0a6a04-e9dc-4b30-a920-6bb228243ab2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_e20c7981-05df-4646-ac70-5d0b040b0116" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_fe17a7a5-4939-47f8-bbe6-4e05618990b9" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_e20c7981-05df-4646-ac70-5d0b040b0116" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_9318d7a5-77fc-44df-ab04-03b578131d5b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_fe17a7a5-4939-47f8-bbe6-4e05618990b9" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_9318d7a5-77fc-44df-ab04-03b578131d5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtInstrumentMaximumBorrowingCapacityAmountOutstanding_ea573737-eaee-427c-8f72-416e841303f4" xlink:href="newt-20241231.xsd#newt_DebtInstrumentMaximumBorrowingCapacityAmountOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_fe17a7a5-4939-47f8-bbe6-4e05618990b9" xlink:to="loc_newt_DebtInstrumentMaximumBorrowingCapacityAmountOutstanding_ea573737-eaee-427c-8f72-416e841303f4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LongTermLineOfCreditNetOfDeferredFinancingCosts_399a7d23-0806-41d8-9680-84d08c4ede5e" xlink:href="newt-20241231.xsd#newt_LongTermLineOfCreditNetOfDeferredFinancingCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_fe17a7a5-4939-47f8-bbe6-4e05618990b9" xlink:to="loc_newt_LongTermLineOfCreditNetOfDeferredFinancingCosts_399a7d23-0806-41d8-9680-84d08c4ede5e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_421b9320-1fda-40ba-a9dd-85856dc89f6f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_fe17a7a5-4939-47f8-bbe6-4e05618990b9" xlink:to="loc_us-gaap_LongTermDebt_421b9320-1fda-40ba-a9dd-85856dc89f6f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_49e3a376-61a8-46d2-a8d2-acd3e826fd1e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtWeightedAverageInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_fe17a7a5-4939-47f8-bbe6-4e05618990b9" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_49e3a376-61a8-46d2-a8d2-acd3e826fd1e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_7e73dc99-23a4-4e77-a323-8a16e122316f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_fe17a7a5-4939-47f8-bbe6-4e05618990b9" xlink:to="loc_us-gaap_Assets_7e73dc99-23a4-4e77-a323-8a16e122316f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankAdvancesValuationAdjustmentsUnderFairValueOption_2a6eef8f-e32f-4b58-a0a7-776f27a36164" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FederalHomeLoanBankAdvancesValuationAdjustmentsUnderFairValueOption"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_fe17a7a5-4939-47f8-bbe6-4e05618990b9" xlink:to="loc_us-gaap_FederalHomeLoanBankAdvancesValuationAdjustmentsUnderFairValueOption_2a6eef8f-e32f-4b58-a0a7-776f27a36164" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BORROWINGSOutstandingBorrowingsDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BORROWINGSOutstandingBorrowingsDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BORROWINGSOutstandingBorrowingsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_1f7abef6-5acb-4046-bc25-1d7dd5019d10" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_04b86a2f-9b69-4023-85d9-30c67235cdf4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1f7abef6-5acb-4046-bc25-1d7dd5019d10" xlink:to="loc_us-gaap_DebtInstrumentTable_04b86a2f-9b69-4023-85d9-30c67235cdf4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_96ef23c8-9fbf-4e54-ba89-a6a65ebf0383" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_04b86a2f-9b69-4023-85d9-30c67235cdf4" xlink:to="loc_us-gaap_DebtInstrumentAxis_96ef23c8-9fbf-4e54-ba89-a6a65ebf0383" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_96ef23c8-9fbf-4e54-ba89-a6a65ebf0383_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_96ef23c8-9fbf-4e54-ba89-a6a65ebf0383" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_96ef23c8-9fbf-4e54-ba89-a6a65ebf0383_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_96ef23c8-9fbf-4e54-ba89-a6a65ebf0383" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_WebsterNMSNoteMember_c3990a96-d759-4927-ae28-a2a7d94f33a6" xlink:href="newt-20241231.xsd#newt_WebsterNMSNoteMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_WebsterNMSNoteMember_c3990a96-d759-4927-ae28-a2a7d94f33a6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CapitalOneFacilitiesMember_e367a77c-32eb-47db-9a08-d22eb8013d95" xlink:href="newt-20241231.xsd#newt_CapitalOneFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_CapitalOneFacilitiesMember_e367a77c-32eb-47db-9a08-d22eb8013d95" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SPVIIDeutscheBankFacilityMember_97d7a076-2f0f-4ea5-9090-62edd81ce426" xlink:href="newt-20241231.xsd#newt_SPVIIDeutscheBankFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_SPVIIDeutscheBankFacilityMember_97d7a076-2f0f-4ea5-9090-62edd81ce426" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SPVIIIOneFloridaBankFacilityMember_ec96f0d0-cd76-4aa2-8bde-9ea3d1af798f" xlink:href="newt-20241231.xsd#newt_SPVIIIOneFloridaBankFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_SPVIIIOneFloridaBankFacilityMember_ec96f0d0-cd76-4aa2-8bde-9ea3d1af798f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2024NotesMember_38761339-dd0a-401c-909d-705337e9a9c4" xlink:href="newt-20241231.xsd#newt_A2024NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_A2024NotesMember_38761339-dd0a-401c-909d-705337e9a9c4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2025500NotesMember_92d2f389-131d-4bb5-8762-9738d49dc37e" xlink:href="newt-20241231.xsd#newt_A2025500NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_A2025500NotesMember_92d2f389-131d-4bb5-8762-9738d49dc37e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20258125NotesMember_68900e0a-474f-4c65-b37e-d6f36dd72a23" xlink:href="newt-20241231.xsd#newt_A20258125NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_A20258125NotesMember_68900e0a-474f-4c65-b37e-d6f36dd72a23" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2026NotesMember_976c6b52-43a6-450a-a303-eb86476ee8b9" xlink:href="newt-20241231.xsd#newt_A2026NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_A2026NotesMember_976c6b52-43a6-450a-a303-eb86476ee8b9" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2027NotesMember_a91d8dc1-646e-458a-b3cd-29936a256a50" xlink:href="newt-20241231.xsd#newt_A2027NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_A2027NotesMember_a91d8dc1-646e-458a-b3cd-29936a256a50" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2028NotesMember_7355eb18-477e-4ef2-b008-de5058937f13" xlink:href="newt-20241231.xsd#newt_A2028NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_A2028NotesMember_7355eb18-477e-4ef2-b008-de5058937f13" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.50NotesMember_2b546a5d-166f-4724-a42e-3712aea9e66e" xlink:href="newt-20241231.xsd#newt_A20298.50NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_A20298.50NotesMember_2b546a5d-166f-4724-a42e-3712aea9e66e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.625NotesMember_79d4e082-8910-4eb9-90fc-d5dc3df9f5d7" xlink:href="newt-20241231.xsd#newt_A20298.625NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_A20298.625NotesMember_79d4e082-8910-4eb9-90fc-d5dc3df9f5d7" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SecuritizationTrustsMember_6ca441f0-ac9f-4c08-b681-aef03d5a5153" xlink:href="newt-20241231.xsd#newt_SecuritizationTrustsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_56b9e039-3503-456c-b1e1-edac9651bab1" xlink:to="loc_newt_SecuritizationTrustsMember_6ca441f0-ac9f-4c08-b681-aef03d5a5153" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_906cc599-24bd-43cd-8e02-853fcdce62c0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_04b86a2f-9b69-4023-85d9-30c67235cdf4" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_906cc599-24bd-43cd-8e02-853fcdce62c0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_906cc599-24bd-43cd-8e02-853fcdce62c0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_906cc599-24bd-43cd-8e02-853fcdce62c0" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_906cc599-24bd-43cd-8e02-853fcdce62c0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_929b98ad-c55c-442a-a13e-3020177caeca" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_906cc599-24bd-43cd-8e02-853fcdce62c0" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_929b98ad-c55c-442a-a13e-3020177caeca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_4b6e00f6-400b-4953-8fc9-aedc1407c8f0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_929b98ad-c55c-442a-a13e-3020177caeca" xlink:to="loc_us-gaap_LineOfCreditMember_4b6e00f6-400b-4953-8fc9-aedc1407c8f0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MediumTermNotesMember_0c244d5a-1577-43fb-b664-90cafe8adcff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MediumTermNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_929b98ad-c55c-442a-a13e-3020177caeca" xlink:to="loc_us-gaap_MediumTermNotesMember_0c244d5a-1577-43fb-b664-90cafe8adcff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_3ffc7280-dd07-452a-a194-1ac40b2b1cab" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_929b98ad-c55c-442a-a13e-3020177caeca" xlink:to="loc_us-gaap_SecuredDebtMember_3ffc7280-dd07-452a-a194-1ac40b2b1cab" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_59e8055b-2d00-4e7a-8b01-7918dd4ea1de" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1f7abef6-5acb-4046-bc25-1d7dd5019d10" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_59e8055b-2d00-4e7a-8b01-7918dd4ea1de" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_4228eaac-167e-4bf7-864e-5be1c203c66b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1f7abef6-5acb-4046-bc25-1d7dd5019d10" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_4228eaac-167e-4bf7-864e-5be1c203c66b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LongTermDebtNetOfDeferredFinancingCosts_d4bcae2e-71bf-4aca-bf87-b3c15a2e17e2" xlink:href="newt-20241231.xsd#newt_LongTermDebtNetOfDeferredFinancingCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1f7abef6-5acb-4046-bc25-1d7dd5019d10" xlink:to="loc_newt_LongTermDebtNetOfDeferredFinancingCosts_d4bcae2e-71bf-4aca-bf87-b3c15a2e17e2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_bcec07a0-f763-4c8b-b1c8-0541813f574a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtWeightedAverageInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1f7abef6-5acb-4046-bc25-1d7dd5019d10" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_bcec07a0-f763-4c8b-b1c8-0541813f574a" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BORROWINGSInterestExpenseDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BORROWINGSInterestExpenseDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BORROWINGSInterestExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_de6ec55a-13f6-4a14-8eed-70a9997f8efb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_d484c82f-e30c-4ec1-8677-52ab4cbca0e0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_de6ec55a-13f6-4a14-8eed-70a9997f8efb" xlink:to="loc_us-gaap_DebtInstrumentTable_d484c82f-e30c-4ec1-8677-52ab4cbca0e0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_2b808f3a-715f-4a99-8998-6835d536038a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_d484c82f-e30c-4ec1-8677-52ab4cbca0e0" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_2b808f3a-715f-4a99-8998-6835d536038a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_2b808f3a-715f-4a99-8998-6835d536038a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_2b808f3a-715f-4a99-8998-6835d536038a" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_2b808f3a-715f-4a99-8998-6835d536038a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_78d4fc0a-e5e8-4858-9ad4-8741f566516e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_2b808f3a-715f-4a99-8998-6835d536038a" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_78d4fc0a-e5e8-4858-9ad4-8741f566516e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MediumTermNotesMember_587fac34-3935-4fee-b6da-b6de3fd031da" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MediumTermNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_78d4fc0a-e5e8-4858-9ad4-8741f566516e" xlink:to="loc_us-gaap_MediumTermNotesMember_587fac34-3935-4fee-b6da-b6de3fd031da" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_6711074d-7f89-444f-8617-50e7870cdb52" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_de6ec55a-13f6-4a14-8eed-70a9997f8efb" xlink:to="loc_us-gaap_InterestExpenseDebt_6711074d-7f89-444f-8617-50e7870cdb52" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BORROWINGS202220232024202520262028and2029NotesDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BORROWINGS202220232024202520262028and2029NotesDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BORROWINGS202220232024202520262028and2029NotesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_e3bd8569-9507-496c-96ca-1520ffba1030" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_us-gaap_DebtInstrumentTable_e3bd8569-9507-496c-96ca-1520ffba1030" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_1514ab76-3348-4b34-9e64-90f717290c22" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_e3bd8569-9507-496c-96ca-1520ffba1030" xlink:to="loc_us-gaap_DebtInstrumentAxis_1514ab76-3348-4b34-9e64-90f717290c22" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_1514ab76-3348-4b34-9e64-90f717290c22_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_1514ab76-3348-4b34-9e64-90f717290c22" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_1514ab76-3348-4b34-9e64-90f717290c22_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_8792428c-8e51-46aa-98a6-787b6d900337" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_1514ab76-3348-4b34-9e64-90f717290c22" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_8792428c-8e51-46aa-98a6-787b6d900337" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.50NotesMember_b6552037-ad9f-47c0-bba4-6a5724514310" xlink:href="newt-20241231.xsd#newt_A20298.50NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_8792428c-8e51-46aa-98a6-787b6d900337" xlink:to="loc_newt_A20298.50NotesMember_b6552037-ad9f-47c0-bba4-6a5724514310" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A20298.625NotesMember_fb16d14a-5dc3-473d-9de0-76656ce368a1" xlink:href="newt-20241231.xsd#newt_A20298.625NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_8792428c-8e51-46aa-98a6-787b6d900337" xlink:to="loc_newt_A20298.625NotesMember_fb16d14a-5dc3-473d-9de0-76656ce368a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2028NotesMember_f30ce10a-8749-4ed6-a6b0-f5867cc4369e" xlink:href="newt-20241231.xsd#newt_A2028NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_8792428c-8e51-46aa-98a6-787b6d900337" xlink:to="loc_newt_A2028NotesMember_f30ce10a-8749-4ed6-a6b0-f5867cc4369e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2026NotesMember_21ddbbc2-5670-45e5-b5b0-dfe5495416ab" xlink:href="newt-20241231.xsd#newt_A2026NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_8792428c-8e51-46aa-98a6-787b6d900337" xlink:to="loc_newt_A2026NotesMember_21ddbbc2-5670-45e5-b5b0-dfe5495416ab" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2026NotesOverallotmentOptionMember_3e77cbd1-ae45-4c43-be6a-5e112b665928" xlink:href="newt-20241231.xsd#newt_A2026NotesOverallotmentOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_A2026NotesMember_21ddbbc2-5670-45e5-b5b0-dfe5495416ab" xlink:to="loc_newt_A2026NotesOverallotmentOptionMember_3e77cbd1-ae45-4c43-be6a-5e112b665928" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2025NotesMember_e575cee5-7b7c-48e6-8b69-dc799839382f" xlink:href="newt-20241231.xsd#newt_A2025NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_8792428c-8e51-46aa-98a6-787b6d900337" xlink:to="loc_newt_A2025NotesMember_e575cee5-7b7c-48e6-8b69-dc799839382f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2024NotesMember_9b1e8e2e-3747-432c-9222-34a10e618c1e" xlink:href="newt-20241231.xsd#newt_A2024NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_8792428c-8e51-46aa-98a6-787b6d900337" xlink:to="loc_newt_A2024NotesMember_9b1e8e2e-3747-432c-9222-34a10e618c1e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_10e71b0c-2e1c-493b-a7d4-d9af24bbc8cd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_e3bd8569-9507-496c-96ca-1520ffba1030" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_10e71b0c-2e1c-493b-a7d4-d9af24bbc8cd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_10e71b0c-2e1c-493b-a7d4-d9af24bbc8cd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_10e71b0c-2e1c-493b-a7d4-d9af24bbc8cd" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_10e71b0c-2e1c-493b-a7d4-d9af24bbc8cd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_4911051f-0ea5-40f6-86fe-9617c3e963a2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_10e71b0c-2e1c-493b-a7d4-d9af24bbc8cd" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_4911051f-0ea5-40f6-86fe-9617c3e963a2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MediumTermNotesMember_3b39c160-ac7f-484f-bbf6-3f699dead133" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MediumTermNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_4911051f-0ea5-40f6-86fe-9617c3e963a2" xlink:to="loc_us-gaap_MediumTermNotesMember_3b39c160-ac7f-484f-bbf6-3f699dead133" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_3e8f7afe-f5e5-4524-a7dd-18040e2fc408" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_3e8f7afe-f5e5-4524-a7dd-18040e2fc408" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_d8bf2a6e-8483-44dc-b0c7-7f8e3db8f7e5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtWeightedAverageInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_d8bf2a6e-8483-44dc-b0c7-7f8e3db8f7e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtInstrumentAdditionalAmountPurchased_aeb18d9a-d389-40cd-a516-e1e2cd31d2db" xlink:href="newt-20241231.xsd#newt_DebtInstrumentAdditionalAmountPurchased"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_newt_DebtInstrumentAdditionalAmountPurchased_aeb18d9a-d389-40cd-a516-e1e2cd31d2db" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfDebt_b601f111-45fa-4e21-8c43-94fc5d1c8c39" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromIssuanceOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfDebt_b601f111-45fa-4e21-8c43-94fc5d1c8c39" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_3a15624c-7244-42a5-ad32-d6502e44940e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_us-gaap_InterestExpenseDebt_3a15624c-7244-42a5-ad32-d6502e44940e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromDebtNetOfIssuanceCosts_860dea32-4f09-45fe-816d-8bd82be78e21" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromDebtNetOfIssuanceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_us-gaap_ProceedsFromDebtNetOfIssuanceCosts_860dea32-4f09-45fe-816d-8bd82be78e21" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtInstrumentAdditionalPrincipalIssuable_df64246f-0b58-4e86-8d5b-8634a9ac3bef" xlink:href="newt-20241231.xsd#newt_DebtInstrumentAdditionalPrincipalIssuable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_newt_DebtInstrumentAdditionalPrincipalIssuable_df64246f-0b58-4e86-8d5b-8634a9ac3bef" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtInstrumentRedemptionPricePerNote_f850b301-9593-493e-92cb-65dff64d7f56" xlink:href="newt-20241231.xsd#newt_DebtInstrumentRedemptionPricePerNote"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_newt_DebtInstrumentRedemptionPricePerNote_f850b301-9593-493e-92cb-65dff64d7f56" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtInstrumentRedeemedAmount_652e8cfd-e341-4935-8144-d7b674394eb9" xlink:href="newt-20241231.xsd#newt_DebtInstrumentRedeemedAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_newt_DebtInstrumentRedeemedAmount_652e8cfd-e341-4935-8144-d7b674394eb9" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_8303ba00-ed88-4102-8dac-ae8218c05988" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_us-gaap_LongTermDebt_8303ba00-ed88-4102-8dac-ae8218c05988" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_0f352a7d-be4b-4567-b4ee-688b886c9bf8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_65a893e7-da5e-4b08-8f01-9b4732aa6aa2" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_0f352a7d-be4b-4567-b4ee-688b886c9bf8" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BORROWINGSSecuritizationTrustsDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BORROWINGSSecuritizationTrustsDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BORROWINGSSecuritizationTrustsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_21789fe0-ff20-4e9e-937c-b14d0da8c41c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_d7f03de2-582e-42d2-ba4f-9bba1d36fa66" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_21789fe0-ff20-4e9e-937c-b14d0da8c41c" xlink:to="loc_us-gaap_DebtInstrumentTable_d7f03de2-582e-42d2-ba4f-9bba1d36fa66" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_8be2ee2c-13b5-4a56-b7a4-f63dff968fe0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_d7f03de2-582e-42d2-ba4f-9bba1d36fa66" xlink:to="loc_us-gaap_DebtInstrumentAxis_8be2ee2c-13b5-4a56-b7a4-f63dff968fe0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_8be2ee2c-13b5-4a56-b7a4-f63dff968fe0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_8be2ee2c-13b5-4a56-b7a4-f63dff968fe0" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_8be2ee2c-13b5-4a56-b7a4-f63dff968fe0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_ad94ac89-daa8-46c7-bc6c-888368bdb0f5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_8be2ee2c-13b5-4a56-b7a4-f63dff968fe0" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_ad94ac89-daa8-46c7-bc6c-888368bdb0f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SecuritizationTrustsMember_ef4277c2-31d5-4c82-8efe-81e6deef681a" xlink:href="newt-20241231.xsd#newt_SecuritizationTrustsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_ad94ac89-daa8-46c7-bc6c-888368bdb0f5" xlink:to="loc_newt_SecuritizationTrustsMember_ef4277c2-31d5-4c82-8efe-81e6deef681a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SecuritizationTrustsClassAMember_8e1fda76-7f02-42d3-9f67-8a856064a2f0" xlink:href="newt-20241231.xsd#newt_SecuritizationTrustsClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_ad94ac89-daa8-46c7-bc6c-888368bdb0f5" xlink:to="loc_newt_SecuritizationTrustsClassAMember_8e1fda76-7f02-42d3-9f67-8a856064a2f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SecuritizationTrustsClassBMember_672f61aa-ba6e-4dfc-bf61-ad15b5c359e5" xlink:href="newt-20241231.xsd#newt_SecuritizationTrustsClassBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_ad94ac89-daa8-46c7-bc6c-888368bdb0f5" xlink:to="loc_newt_SecuritizationTrustsClassBMember_672f61aa-ba6e-4dfc-bf61-ad15b5c359e5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_0d96d0df-96ea-4e17-95ba-c5ad9e38dbd9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_d7f03de2-582e-42d2-ba4f-9bba1d36fa66" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_0d96d0df-96ea-4e17-95ba-c5ad9e38dbd9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_0d96d0df-96ea-4e17-95ba-c5ad9e38dbd9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_0d96d0df-96ea-4e17-95ba-c5ad9e38dbd9" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_0d96d0df-96ea-4e17-95ba-c5ad9e38dbd9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_dfb05169-c817-4d6c-b2d0-ed18acc912f3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_0d96d0df-96ea-4e17-95ba-c5ad9e38dbd9" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_dfb05169-c817-4d6c-b2d0-ed18acc912f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_0d9bd96b-01a9-4334-a55a-be53bb1aefea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_dfb05169-c817-4d6c-b2d0-ed18acc912f3" xlink:to="loc_us-gaap_SecuredDebtMember_0d9bd96b-01a9-4334-a55a-be53bb1aefea" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateAxis_06db44e4-558c-465c-80e6-ccfc788a6c33" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_VariableRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_d7f03de2-582e-42d2-ba4f-9bba1d36fa66" xlink:to="loc_us-gaap_VariableRateAxis_06db44e4-558c-465c-80e6-ccfc788a6c33" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_06db44e4-558c-465c-80e6-ccfc788a6c33_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_06db44e4-558c-465c-80e6-ccfc788a6c33" xlink:to="loc_us-gaap_VariableRateDomain_06db44e4-558c-465c-80e6-ccfc788a6c33_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_539b8c44-22e6-40ae-b940-9e764ca23dd9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_06db44e4-558c-465c-80e6-ccfc788a6c33" xlink:to="loc_us-gaap_VariableRateDomain_539b8c44-22e6-40ae-b940-9e764ca23dd9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LIBORMember_88b9f147-cc00-4802-81be-cf224682f1ac" xlink:href="newt-20241231.xsd#newt_LIBORMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_539b8c44-22e6-40ae-b940-9e764ca23dd9" xlink:to="loc_newt_LIBORMember_88b9f147-cc00-4802-81be-cf224682f1ac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_6ab74d7f-5ef1-4891-b8c0-92a88bbe7a8d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_539b8c44-22e6-40ae-b940-9e764ca23dd9" xlink:to="loc_us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_6ab74d7f-5ef1-4891-b8c0-92a88bbe7a8d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtInstrumentTransferAmount_8b605d36-15b9-4060-878a-88c7ac488def" xlink:href="newt-20241231.xsd#newt_DebtInstrumentTransferAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_21789fe0-ff20-4e9e-937c-b14d0da8c41c" xlink:to="loc_newt_DebtInstrumentTransferAmount_8b605d36-15b9-4060-878a-88c7ac488def" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_1336b46a-67c9-4222-ad3c-816d7be1257c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_21789fe0-ff20-4e9e-937c-b14d0da8c41c" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_1336b46a-67c9-4222-ad3c-816d7be1257c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_32f3f9cf-15a3-4d9c-820b-803b183df83a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_21789fe0-ff20-4e9e-937c-b14d0da8c41c" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_32f3f9cf-15a3-4d9c-820b-803b183df83a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_5bf78af7-7d39-4f83-842a-638082caec98" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_21789fe0-ff20-4e9e-937c-b14d0da8c41c" xlink:to="loc_us-gaap_InterestExpenseDebt_5bf78af7-7d39-4f83-842a-638082caec98" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_72badffb-3aa7-4552-acd7-de9eed15ca3f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_21789fe0-ff20-4e9e-937c-b14d0da8c41c" xlink:to="loc_us-gaap_Assets_72badffb-3aa7-4552-acd7-de9eed15ca3f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_9c4b8181-b1fc-4db8-ba68-f00df4f39ff3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_21789fe0-ff20-4e9e-937c-b14d0da8c41c" xlink:to="loc_us-gaap_Liabilities_9c4b8181-b1fc-4db8-ba68-f00df4f39ff3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPricePercentage_2b2b7416-f700-4fe6-9aff-5c11e6cf52cf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentRedemptionPricePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_21789fe0-ff20-4e9e-937c-b14d0da8c41c" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPricePercentage_2b2b7416-f700-4fe6-9aff-5c11e6cf52cf" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BORROWINGSCapitalOneFacilityDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BORROWINGSCapitalOneFacilityDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BORROWINGSCapitalOneFacilityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_b985dd41-6346-4e53-a1d8-60fc39484631" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_fa1a3a33-82a7-4e7f-a15a-01e186ac0179" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_b985dd41-6346-4e53-a1d8-60fc39484631" xlink:to="loc_us-gaap_DebtInstrumentTable_fa1a3a33-82a7-4e7f-a15a-01e186ac0179" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_5f86189d-0bee-488d-97ba-1e6bfb8131f3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_fa1a3a33-82a7-4e7f-a15a-01e186ac0179" xlink:to="loc_us-gaap_CreditFacilityAxis_5f86189d-0bee-488d-97ba-1e6bfb8131f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_5f86189d-0bee-488d-97ba-1e6bfb8131f3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_5f86189d-0bee-488d-97ba-1e6bfb8131f3" xlink:to="loc_us-gaap_CreditFacilityDomain_5f86189d-0bee-488d-97ba-1e6bfb8131f3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_da745812-f03d-4142-8190-74c69cfe1356" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_5f86189d-0bee-488d-97ba-1e6bfb8131f3" xlink:to="loc_us-gaap_CreditFacilityDomain_da745812-f03d-4142-8190-74c69cfe1356" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CapitalOneGuaranteedAndUnguaranteedMember_e19205bb-ee4b-4141-9674-a923afe88a5d" xlink:href="newt-20241231.xsd#newt_CapitalOneGuaranteedAndUnguaranteedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_da745812-f03d-4142-8190-74c69cfe1356" xlink:to="loc_newt_CapitalOneGuaranteedAndUnguaranteedMember_e19205bb-ee4b-4141-9674-a923afe88a5d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CapitalOneGuaranteedMember_215fd1f4-3b21-4bba-9f31-a52492d6cb00" xlink:href="newt-20241231.xsd#newt_CapitalOneGuaranteedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_da745812-f03d-4142-8190-74c69cfe1356" xlink:to="loc_newt_CapitalOneGuaranteedMember_215fd1f4-3b21-4bba-9f31-a52492d6cb00" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CapitalOneUnguaranteedMember_a917600c-70a1-4a22-b142-1de833cc47a2" xlink:href="newt-20241231.xsd#newt_CapitalOneUnguaranteedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_da745812-f03d-4142-8190-74c69cfe1356" xlink:to="loc_newt_CapitalOneUnguaranteedMember_a917600c-70a1-4a22-b142-1de833cc47a2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_811c7ff2-8c03-4d8b-a42b-3950e122092e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_fa1a3a33-82a7-4e7f-a15a-01e186ac0179" xlink:to="loc_us-gaap_DebtInstrumentAxis_811c7ff2-8c03-4d8b-a42b-3950e122092e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_811c7ff2-8c03-4d8b-a42b-3950e122092e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_811c7ff2-8c03-4d8b-a42b-3950e122092e" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_811c7ff2-8c03-4d8b-a42b-3950e122092e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_0147e4dd-a053-4116-94d7-1b57717d618d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_811c7ff2-8c03-4d8b-a42b-3950e122092e" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_0147e4dd-a053-4116-94d7-1b57717d618d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CapitalOneFacilitiesMember_64e09bf6-9a0c-4181-9ae0-5ca0c3798bd5" xlink:href="newt-20241231.xsd#newt_CapitalOneFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0147e4dd-a053-4116-94d7-1b57717d618d" xlink:to="loc_newt_CapitalOneFacilitiesMember_64e09bf6-9a0c-4181-9ae0-5ca0c3798bd5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_02f1da0b-dc43-4478-86b4-d015593fc551" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_fa1a3a33-82a7-4e7f-a15a-01e186ac0179" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_02f1da0b-dc43-4478-86b4-d015593fc551" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_02f1da0b-dc43-4478-86b4-d015593fc551_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_02f1da0b-dc43-4478-86b4-d015593fc551" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_02f1da0b-dc43-4478-86b4-d015593fc551_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_5bfac6cd-3893-45c0-a6fd-465c96c7802e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_02f1da0b-dc43-4478-86b4-d015593fc551" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_5bfac6cd-3893-45c0-a6fd-465c96c7802e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_6ba42ee7-3e2b-4a5f-ab99-96d792b0422a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_5bfac6cd-3893-45c0-a6fd-465c96c7802e" xlink:to="loc_us-gaap_LineOfCreditMember_6ba42ee7-3e2b-4a5f-ab99-96d792b0422a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCredit_e111020e-96eb-4f73-bb58-3f4bad69f24d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LineOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_b985dd41-6346-4e53-a1d8-60fc39484631" xlink:to="loc_us-gaap_LineOfCredit_e111020e-96eb-4f73-bb58-3f4bad69f24d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_01ac2634-7676-4466-a8d0-f572011fb4d3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_b985dd41-6346-4e53-a1d8-60fc39484631" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_01ac2634-7676-4466-a8d0-f572011fb4d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtInstrumentAdvanceRate_bba8f87b-4b8b-401a-8d9f-426e8d645a1e" xlink:href="newt-20241231.xsd#newt_DebtInstrumentAdvanceRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_b985dd41-6346-4e53-a1d8-60fc39484631" xlink:to="loc_newt_DebtInstrumentAdvanceRate_bba8f87b-4b8b-401a-8d9f-426e8d645a1e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_0ea7feee-33d6-476b-8467-03a91b8e2bfa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_b985dd41-6346-4e53-a1d8-60fc39484631" xlink:to="loc_us-gaap_InterestExpenseDebt_0ea7feee-33d6-476b-8467-03a91b8e2bfa" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BORROWINGSNotesPayableRelatedPartiesDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BORROWINGSNotesPayableRelatedPartiesDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BORROWINGSNotesPayableRelatedPartiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_5cfe952a-9e2c-4948-ad29-b9b51d708474" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_7617a532-83c1-4589-8eff-92ee1a67994d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5cfe952a-9e2c-4948-ad29-b9b51d708474" xlink:to="loc_us-gaap_DebtInstrumentTable_7617a532-83c1-4589-8eff-92ee1a67994d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_174dc567-ffb5-470f-b583-82dacc7c7908" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_7617a532-83c1-4589-8eff-92ee1a67994d" xlink:to="loc_us-gaap_DebtInstrumentAxis_174dc567-ffb5-470f-b583-82dacc7c7908" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_174dc567-ffb5-470f-b583-82dacc7c7908_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_174dc567-ffb5-470f-b583-82dacc7c7908" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_174dc567-ffb5-470f-b583-82dacc7c7908_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_36493b40-6a54-4840-957c-9adf6fc3709b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_174dc567-ffb5-470f-b583-82dacc7c7908" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_36493b40-6a54-4840-957c-9adf6fc3709b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_RelatedPartyNotesPayableMember_dcc620e7-12b7-4983-bdd0-bbabc2c66366" xlink:href="newt-20241231.xsd#newt_RelatedPartyNotesPayableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_36493b40-6a54-4840-957c-9adf6fc3709b" xlink:to="loc_newt_RelatedPartyNotesPayableMember_dcc620e7-12b7-4983-bdd0-bbabc2c66366" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_549a1361-e753-4bd9-a0b1-d1c9f251ee24" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_7617a532-83c1-4589-8eff-92ee1a67994d" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_549a1361-e753-4bd9-a0b1-d1c9f251ee24" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_549a1361-e753-4bd9-a0b1-d1c9f251ee24_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_549a1361-e753-4bd9-a0b1-d1c9f251ee24" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_549a1361-e753-4bd9-a0b1-d1c9f251ee24_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_f6935db9-e18b-47fb-9d6e-80d0688b829f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_549a1361-e753-4bd9-a0b1-d1c9f251ee24" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_f6935db9-e18b-47fb-9d6e-80d0688b829f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_7cff8475-00b2-4234-8eb4-11314c416fec" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_f6935db9-e18b-47fb-9d6e-80d0688b829f" xlink:to="loc_us-gaap_LineOfCreditMember_7cff8475-00b2-4234-8eb4-11314c416fec" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateAxis_591c2c1c-6dce-4e06-b930-836d7d434c03" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_VariableRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_7617a532-83c1-4589-8eff-92ee1a67994d" xlink:to="loc_us-gaap_VariableRateAxis_591c2c1c-6dce-4e06-b930-836d7d434c03" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_591c2c1c-6dce-4e06-b930-836d7d434c03_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_591c2c1c-6dce-4e06-b930-836d7d434c03" xlink:to="loc_us-gaap_VariableRateDomain_591c2c1c-6dce-4e06-b930-836d7d434c03_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_f32a3896-d8df-49e4-ad24-7f6433c8fab3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_591c2c1c-6dce-4e06-b930-836d7d434c03" xlink:to="loc_us-gaap_VariableRateDomain_f32a3896-d8df-49e4-ad24-7f6433c8fab3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LIBORMember_6b665add-da3e-4f25-8868-dc7653241030" xlink:href="newt-20241231.xsd#newt_LIBORMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_f32a3896-d8df-49e4-ad24-7f6433c8fab3" xlink:to="loc_newt_LIBORMember_6b665add-da3e-4f25-8868-dc7653241030" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrimeRateMember_96670694-bb24-4f72-aa4c-fe8faae48c9c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PrimeRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_f32a3896-d8df-49e4-ad24-7f6433c8fab3" xlink:to="loc_us-gaap_PrimeRateMember_96670694-bb24-4f72-aa4c-fe8faae48c9c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_3b46faf1-1c73-4628-8292-853350e1fefc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_7617a532-83c1-4589-8eff-92ee1a67994d" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_3b46faf1-1c73-4628-8292-853350e1fefc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_3b46faf1-1c73-4628-8292-853350e1fefc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_3b46faf1-1c73-4628-8292-853350e1fefc" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_3b46faf1-1c73-4628-8292-853350e1fefc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_ac301171-eca5-4715-8104-08f132e33b44" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_3b46faf1-1c73-4628-8292-853350e1fefc" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_ac301171-eca5-4715-8104-08f132e33b44" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_RelatedPartyRLOCMember_c6bd218b-349c-4165-aae8-d086ea2f6e6e" xlink:href="newt-20241231.xsd#newt_RelatedPartyRLOCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_ac301171-eca5-4715-8104-08f132e33b44" xlink:to="loc_newt_RelatedPartyRLOCMember_c6bd218b-349c-4165-aae8-d086ea2f6e6e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_2cffe78b-153e-4f44-b89d-1a8121cb7b3f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5cfe952a-9e2c-4948-ad29-b9b51d708474" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_2cffe78b-153e-4f44-b89d-1a8121cb7b3f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DebtInstrumentInterestRateFloor_40a4f7b3-29c3-4972-98a2-acb7d97c8e5c" xlink:href="newt-20241231.xsd#newt_DebtInstrumentInterestRateFloor"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5cfe952a-9e2c-4948-ad29-b9b51d708474" xlink:to="loc_newt_DebtInstrumentInterestRateFloor_40a4f7b3-29c3-4972-98a2-acb7d97c8e5c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_3a136ad1-333d-4a7b-80a0-c2b1d63f5bd0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5cfe952a-9e2c-4948-ad29-b9b51d708474" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_3a136ad1-333d-4a7b-80a0-c2b1d63f5bd0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_966e5cbb-51f5-48ac-bc80-12b89b0e43c2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5cfe952a-9e2c-4948-ad29-b9b51d708474" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_966e5cbb-51f5-48ac-bc80-12b89b0e43c2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_68939227-20cc-4a81-979c-1a8d02a1566c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5cfe952a-9e2c-4948-ad29-b9b51d708474" xlink:to="loc_us-gaap_InterestExpenseDebt_68939227-20cc-4a81-979c-1a8d02a1566c" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/DERIVATIVEINSTRUMENTSDerivativesOutstandingDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#DERIVATIVEINSTRUMENTSDerivativesOutstandingDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/DERIVATIVEINSTRUMENTSDerivativesOutstandingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_5f21e513-c57f-4248-8966-9d6046cf38ac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_e4d610df-39b9-47be-b573-fe9ca3d0c52a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_5f21e513-c57f-4248-8966-9d6046cf38ac" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_e4d610df-39b9-47be-b573-fe9ca3d0c52a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_53c06cfc-e94b-4020-aca1-5a2e826240de" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_e4d610df-39b9-47be-b573-fe9ca3d0c52a" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_53c06cfc-e94b-4020-aca1-5a2e826240de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_53c06cfc-e94b-4020-aca1-5a2e826240de_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_53c06cfc-e94b-4020-aca1-5a2e826240de" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_53c06cfc-e94b-4020-aca1-5a2e826240de_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_590fe28f-b0ea-4c15-87df-644aef2ef10c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_53c06cfc-e94b-4020-aca1-5a2e826240de" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_590fe28f-b0ea-4c15-87df-644aef2ef10c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeFutureMember_c11a4f76-a491-44f8-872a-48c0760c07af" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignExchangeFutureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_590fe28f-b0ea-4c15-87df-644aef2ef10c" xlink:to="loc_us-gaap_ForeignExchangeFutureMember_c11a4f76-a491-44f8-872a-48c0760c07af" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PositionAxis_88609001-67ff-48ad-bcae-7a0b2087ffab" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PositionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_e4d610df-39b9-47be-b573-fe9ca3d0c52a" xlink:to="loc_us-gaap_PositionAxis_88609001-67ff-48ad-bcae-7a0b2087ffab" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PositionDomain_88609001-67ff-48ad-bcae-7a0b2087ffab_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PositionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PositionAxis_88609001-67ff-48ad-bcae-7a0b2087ffab" xlink:to="loc_us-gaap_PositionDomain_88609001-67ff-48ad-bcae-7a0b2087ffab_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PositionDomain_5e267aed-55e0-406c-be92-162b8a9fa783" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PositionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PositionAxis_88609001-67ff-48ad-bcae-7a0b2087ffab" xlink:to="loc_us-gaap_PositionDomain_5e267aed-55e0-406c-be92-162b8a9fa783" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortMember_c4ccd636-5b43-440b-a9eb-80d52f972022" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShortMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PositionDomain_5e267aed-55e0-406c-be92-162b8a9fa783" xlink:to="loc_us-gaap_ShortMember_c4ccd636-5b43-440b-a9eb-80d52f972022" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_71ae3c28-27bb-4d48-91d4-8705c8fa4995" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_5f21e513-c57f-4248-8966-9d6046cf38ac" xlink:to="loc_us-gaap_DerivativeNotionalAmount_71ae3c28-27bb-4d48-91d4-8705c8fa4995" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_b3f3be69-74d1-487c-a70a-41e35a4e3ec4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_5f21e513-c57f-4248-8966-9d6046cf38ac" xlink:to="loc_us-gaap_DerivativeAssets_b3f3be69-74d1-487c-a70a-41e35a4e3ec4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_c63c9ac7-0ec3-47d6-adfc-059446e2679a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_5f21e513-c57f-4248-8966-9d6046cf38ac" xlink:to="loc_us-gaap_DerivativeLiabilities_c63c9ac7-0ec3-47d6-adfc-059446e2679a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeRemainingMaturity1_f06c17a5-e598-48a1-9d24-edc21f9daae3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeRemainingMaturity1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_5f21e513-c57f-4248-8966-9d6046cf38ac" xlink:to="loc_us-gaap_DerivativeRemainingMaturity1_f06c17a5-e598-48a1-9d24-edc21f9daae3" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/DERIVATIVEINSTRUMENTSGainsandLossesDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#DERIVATIVEINSTRUMENTSGainsandLossesDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/DERIVATIVEINSTRUMENTSGainsandLossesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_1c6b3c5a-8128-466e-b2ac-2ccd53afb7dd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_718c75ec-c398-4a36-893f-9c0e5a272f67" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_1c6b3c5a-8128-466e-b2ac-2ccd53afb7dd" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_718c75ec-c398-4a36-893f-9c0e5a272f67" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_8b359d5f-90f6-41c1-a9b8-ee6818978583" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_718c75ec-c398-4a36-893f-9c0e5a272f67" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_8b359d5f-90f6-41c1-a9b8-ee6818978583" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_8b359d5f-90f6-41c1-a9b8-ee6818978583_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_8b359d5f-90f6-41c1-a9b8-ee6818978583" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_8b359d5f-90f6-41c1-a9b8-ee6818978583_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_9d708fdd-b490-4524-a242-91b66cba917f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_8b359d5f-90f6-41c1-a9b8-ee6818978583" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_9d708fdd-b490-4524-a242-91b66cba917f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeFutureMember_955d05d6-46fe-4229-8000-bfdea36e63d0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignExchangeFutureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_9d708fdd-b490-4524-a242-91b66cba917f" xlink:to="loc_us-gaap_ForeignExchangeFutureMember_955d05d6-46fe-4229-8000-bfdea36e63d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_479f71a2-f1ed-45fd-afcc-794d5b172b21" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_1c6b3c5a-8128-466e-b2ac-2ccd53afb7dd" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_479f71a2-f1ed-45fd-afcc-794d5b172b21" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfDerivatives_8a6a63e6-66a7-4e16-bc92-6dcfd2f759d1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainLossOnSaleOfDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_1c6b3c5a-8128-466e-b2ac-2ccd53afb7dd" xlink:to="loc_us-gaap_GainLossOnSaleOfDerivatives_8a6a63e6-66a7-4e16-bc92-6dcfd2f759d1" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/COMMITMENTSANDCONTINGENCIESNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#COMMITMENTSANDCONTINGENCIESNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/COMMITMENTSANDCONTINGENCIESNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsLineItems_cc76b607-b401-4360-b52c-2ed1174a0ccb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCommitmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsTable_49e0e6c6-bc05-4cf7-9b04-df68410f5763" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCommitmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_cc76b607-b401-4360-b52c-2ed1174a0ccb" xlink:to="loc_us-gaap_OtherCommitmentsTable_49e0e6c6-bc05-4cf7-9b04-df68410f5763" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_68799f42-5cac-4284-aef3-0c9d272d2836" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OtherCommitmentsTable_49e0e6c6-bc05-4cf7-9b04-df68410f5763" xlink:to="loc_us-gaap_FinancialInstrumentAxis_68799f42-5cac-4284-aef3-0c9d272d2836" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_68799f42-5cac-4284-aef3-0c9d272d2836_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_68799f42-5cac-4284-aef3-0c9d272d2836" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_68799f42-5cac-4284-aef3-0c9d272d2836_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d2e95696-72ab-457d-b270-bf972889dc54" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_68799f42-5cac-4284-aef3-0c9d272d2836" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d2e95696-72ab-457d-b270-bf972889dc54" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsToExtendCreditMember_75e4b96d-1118-4d77-a226-2b7c5f734ed0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommitmentsToExtendCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d2e95696-72ab-457d-b270-bf972889dc54" xlink:to="loc_us-gaap_CommitmentsToExtendCreditMember_75e4b96d-1118-4d77-a226-2b7c5f734ed0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBA7aLoanMember_c11d52b0-c29b-40d9-9e04-c1062a34be15" xlink:href="newt-20241231.xsd#newt_SBA7aLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d2e95696-72ab-457d-b270-bf972889dc54" xlink:to="loc_newt_SBA7aLoanMember_c11d52b0-c29b-40d9-9e04-c1062a34be15" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A504LoanMember_c8096d67-f0d4-440c-a0fe-5a070e7208f3" xlink:href="newt-20241231.xsd#newt_A504LoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d2e95696-72ab-457d-b270-bf972889dc54" xlink:to="loc_newt_A504LoanMember_c8096d67-f0d4-440c-a0fe-5a070e7208f3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ALPLoansMember_5fa82cb4-df08-4bf0-a862-7563fbb81c39" xlink:href="newt-20241231.xsd#newt_ALPLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d2e95696-72ab-457d-b270-bf972889dc54" xlink:to="loc_newt_ALPLoansMember_5fa82cb4-df08-4bf0-a862-7563fbb81c39" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_CommercialAndIndustrialLoansMember_f67c6e94-d903-4a15-a98f-1ccb41c6637d" xlink:href="newt-20241231.xsd#newt_CommercialAndIndustrialLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d2e95696-72ab-457d-b270-bf972889dc54" xlink:to="loc_newt_CommercialAndIndustrialLoansMember_f67c6e94-d903-4a15-a98f-1ccb41c6637d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountLiability_378fb820-6c9d-4723-8fe8-6cfc5282ed92" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_cc76b607-b401-4360-b52c-2ed1174a0ccb" xlink:to="loc_us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountLiability_378fb820-6c9d-4723-8fe8-6cfc5282ed92" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/SHAREHOLDERSEQUITYNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#SHAREHOLDERSEQUITYNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/SHAREHOLDERSEQUITYNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiarySaleOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_ea986742-da6c-4027-a291-de52f54ea920" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_ea986742-da6c-4027-a291-de52f54ea920" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_8a541826-3d8e-4efc-8944-e203af7dd565" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiarySaleOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_ea986742-da6c-4027-a291-de52f54ea920" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_8a541826-3d8e-4efc-8944-e203af7dd565" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_8a541826-3d8e-4efc-8944-e203af7dd565_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_8a541826-3d8e-4efc-8944-e203af7dd565" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_8a541826-3d8e-4efc-8944-e203af7dd565_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_c4bfed88-7c3b-49c7-bd13-e137c2e7a331" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_8a541826-3d8e-4efc-8944-e203af7dd565" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_c4bfed88-7c3b-49c7-bd13-e137c2e7a331" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2023ATMEquityDistributionMember_387683ea-a7c5-4de1-b37d-51874224f8f9" xlink:href="newt-20241231.xsd#newt_A2023ATMEquityDistributionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_c4bfed88-7c3b-49c7-bd13-e137c2e7a331" xlink:to="loc_newt_A2023ATMEquityDistributionMember_387683ea-a7c5-4de1-b37d-51874224f8f9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2020ATMEquityDistributionMember_f44f541d-f111-41b3-b51e-83b08918c5f0" xlink:href="newt-20241231.xsd#newt_A2020ATMEquityDistributionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_c4bfed88-7c3b-49c7-bd13-e137c2e7a331" xlink:to="loc_newt_A2020ATMEquityDistributionMember_f44f541d-f111-41b3-b51e-83b08918c5f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_59bd94e3-7817-4268-87b6-e9494d3065f4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_ea986742-da6c-4027-a291-de52f54ea920" xlink:to="loc_us-gaap_StatementClassOfStockAxis_59bd94e3-7817-4268-87b6-e9494d3065f4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_59bd94e3-7817-4268-87b6-e9494d3065f4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_59bd94e3-7817-4268-87b6-e9494d3065f4" xlink:to="loc_us-gaap_ClassOfStockDomain_59bd94e3-7817-4268-87b6-e9494d3065f4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_9c3b5616-7bc8-40cd-b1fe-dde162f270e5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_59bd94e3-7817-4268-87b6-e9494d3065f4" xlink:to="loc_us-gaap_ClassOfStockDomain_9c3b5616-7bc8-40cd-b1fe-dde162f270e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SeriesAConvertiblePreferredStockMember_97ea0dc6-0b4d-4978-b786-d3e7d1759532" xlink:href="newt-20241231.xsd#newt_SeriesAConvertiblePreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_9c3b5616-7bc8-40cd-b1fe-dde162f270e5" xlink:to="loc_newt_SeriesAConvertiblePreferredStockMember_97ea0dc6-0b4d-4978-b786-d3e7d1759532" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_c1e779e1-6e61-4393-b30d-8b0654b1d0ba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_c1e779e1-6e61-4393-b30d-8b0654b1d0ba" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_3c6f45d5-fe5e-433a-be46-7c231835d55b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_us-gaap_PreferredStockParOrStatedValuePerShare_3c6f45d5-fe5e-433a-be46-7c231835d55b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_80fc7434-79a3-4af7-a9a7-580d7a590c43" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_80fc7434-79a3-4af7-a9a7-580d7a590c43" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesIssuedPricePerShare_19a1ca16-3d45-44f5-b699-0b44070f21e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SharesIssuedPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_us-gaap_SharesIssuedPricePerShare_19a1ca16-3d45-44f5-b699-0b44070f21e2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockConvertibleSharesIssuable_52ef71d2-f466-4fcc-b85e-c5b21fb7e765" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockConvertibleSharesIssuable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_us-gaap_PreferredStockConvertibleSharesIssuable_52ef71d2-f466-4fcc-b85e-c5b21fb7e765" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightUnissued_246e075d-4622-4c1a-92d9-85a82189cff3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfWarrantOrRightUnissued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_us-gaap_ClassOfWarrantOrRightUnissued_246e075d-4622-4c1a-92d9-85a82189cff3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_072c3ee5-27b4-483c-8568-8814ef4f00a1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_072c3ee5-27b4-483c-8568-8814ef4f00a1" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantsAndRightsOutstandingTerm_68310e1e-6652-4fa4-af2c-9dbb232db7ba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_WarrantsAndRightsOutstandingTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_us-gaap_WarrantsAndRightsOutstandingTerm_68310e1e-6652-4fa4-af2c-9dbb232db7ba" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SaleOfStockNumberOfSharesAuthorizedForSale_85e49f5a-6f04-479c-9f63-3ad90dbe289d" xlink:href="newt-20241231.xsd#newt_SaleOfStockNumberOfSharesAuthorizedForSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_newt_SaleOfStockNumberOfSharesAuthorizedForSale_85e49f5a-6f04-479c-9f63-3ad90dbe289d" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased_469b9722-52e7-428c-af7e-8f850c444f49" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6f45644-98b3-4d49-ae06-783d2cdaaa49" xlink:to="loc_srt_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased_469b9722-52e7-428c-af7e-8f850c444f49" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/SHAREHOLDERSEQUITYATMEquityDistributionDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#SHAREHOLDERSEQUITYATMEquityDistributionDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/SHAREHOLDERSEQUITYATMEquityDistributionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockLineItems_12c7db7a-d5d2-4cf0-9f17-269c88541e4f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiarySaleOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_b5d0c74e-cdf7-422f-9138-b91e312ab306" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_12c7db7a-d5d2-4cf0-9f17-269c88541e4f" xlink:to="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_b5d0c74e-cdf7-422f-9138-b91e312ab306" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_56459a30-82b0-4cb4-91ec-306a010b292b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiarySaleOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_b5d0c74e-cdf7-422f-9138-b91e312ab306" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_56459a30-82b0-4cb4-91ec-306a010b292b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_56459a30-82b0-4cb4-91ec-306a010b292b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_56459a30-82b0-4cb4-91ec-306a010b292b" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_56459a30-82b0-4cb4-91ec-306a010b292b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_d06e712e-095f-467c-aea7-2363e8b9e40f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_56459a30-82b0-4cb4-91ec-306a010b292b" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_d06e712e-095f-467c-aea7-2363e8b9e40f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2023ATMEquityDistributionMember_5fd921ee-2be9-40bf-a743-0d0b2e3f0c53" xlink:href="newt-20241231.xsd#newt_A2023ATMEquityDistributionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_d06e712e-095f-467c-aea7-2363e8b9e40f" xlink:to="loc_newt_A2023ATMEquityDistributionMember_5fd921ee-2be9-40bf-a743-0d0b2e3f0c53" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2020ATMEquityDistributionMember_762f64ff-90c3-486e-9cec-d0b7437cd474" xlink:href="newt-20241231.xsd#newt_A2020ATMEquityDistributionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_d06e712e-095f-467c-aea7-2363e8b9e40f" xlink:to="loc_newt_A2020ATMEquityDistributionMember_762f64ff-90c3-486e-9cec-d0b7437cd474" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_44f4dcc8-67c3-493c-8b4e-177f33ea11a7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_12c7db7a-d5d2-4cf0-9f17-269c88541e4f" xlink:to="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_44f4dcc8-67c3-493c-8b4e-177f33ea11a7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockPricePerShare_2fdb22eb-e4fa-4024-9dd7-322875ca4ee3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SaleOfStockPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_12c7db7a-d5d2-4cf0-9f17-269c88541e4f" xlink:to="loc_us-gaap_SaleOfStockPricePerShare_2fdb22eb-e4fa-4024-9dd7-322875ca4ee3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_3855a43f-a7e4-4dcb-9882-5ec8b8aba5ff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_12c7db7a-d5d2-4cf0-9f17-269c88541e4f" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_3855a43f-a7e4-4dcb-9882-5ec8b8aba5ff" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_8e71ecf5-e320-46d9-a9d0-ca26490f7c50" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_12c7db7a-d5d2-4cf0-9f17-269c88541e4f" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_8e71ecf5-e320-46d9-a9d0-ca26490f7c50" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/SHAREHOLDERSEQUITYShareRepurchaseProgramDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#SHAREHOLDERSEQUITYShareRepurchaseProgramDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/SHAREHOLDERSEQUITYShareRepurchaseProgramDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6fa9249-9c90-4a6a-a84f-146481f85194" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiarySaleOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_588da0c8-17b1-44ae-ada4-1ed823c7de96" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6fa9249-9c90-4a6a-a84f-146481f85194" xlink:to="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_588da0c8-17b1-44ae-ada4-1ed823c7de96" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_a81bd5e3-87c9-4c89-85a4-3819fb852ebf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiarySaleOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_588da0c8-17b1-44ae-ada4-1ed823c7de96" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_a81bd5e3-87c9-4c89-85a4-3819fb852ebf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_a81bd5e3-87c9-4c89-85a4-3819fb852ebf_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_a81bd5e3-87c9-4c89-85a4-3819fb852ebf" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_a81bd5e3-87c9-4c89-85a4-3819fb852ebf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_91698bbe-7118-49a3-8b4d-1aea38ed1546" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_a81bd5e3-87c9-4c89-85a4-3819fb852ebf" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_91698bbe-7118-49a3-8b4d-1aea38ed1546" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_b3a28e1c-4545-45f0-bb59-f0461a2f2c1b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockRepurchasedDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6fa9249-9c90-4a6a-a84f-146481f85194" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_b3a28e1c-4545-45f0-bb59-f0461a2f2c1b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_StockRepurchasedDuringPeriodWeightedAveragePricePerShare_5c9b0b4d-6b7d-4dbb-a0dd-fd67e31b6b66" xlink:href="newt-20241231.xsd#newt_StockRepurchasedDuringPeriodWeightedAveragePricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6fa9249-9c90-4a6a-a84f-146481f85194" xlink:to="loc_newt_StockRepurchasedDuringPeriodWeightedAveragePricePerShare_5c9b0b4d-6b7d-4dbb-a0dd-fd67e31b6b66" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodValue_121435e2-7617-4598-b703-c4b0320e7541" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockRepurchasedDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_d6fa9249-9c90-4a6a-a84f-146481f85194" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodValue_121435e2-7617-4598-b703-c4b0320e7541" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/SHAREHOLDERSEQUITYDividendsDeclaredandDistributedDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#SHAREHOLDERSEQUITYDividendsDeclaredandDistributedDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/SHAREHOLDERSEQUITYDividendsDeclaredandDistributedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockLineItems_b6d14f1f-6c17-476d-9a71-0a41c9699d1a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiarySaleOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_7128a2b0-2014-4529-bc71-5f5176e78544" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_b6d14f1f-6c17-476d-9a71-0a41c9699d1a" xlink:to="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_7128a2b0-2014-4529-bc71-5f5176e78544" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_f9560b4b-c95b-47a8-b7ef-e620bc37899b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_7128a2b0-2014-4529-bc71-5f5176e78544" xlink:to="loc_us-gaap_AwardTypeAxis_f9560b4b-c95b-47a8-b7ef-e620bc37899b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_f9560b4b-c95b-47a8-b7ef-e620bc37899b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_f9560b4b-c95b-47a8-b7ef-e620bc37899b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_f9560b4b-c95b-47a8-b7ef-e620bc37899b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_d6f6f620-0209-4cd3-854d-51b0214d00de" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_f9560b4b-c95b-47a8-b7ef-e620bc37899b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_d6f6f620-0209-4cd3-854d-51b0214d00de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_UnvestedRestrictedStockMember_e34e03ff-dba2-4cb8-9c4b-b7e29a7c5795" xlink:href="newt-20241231.xsd#newt_UnvestedRestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_d6f6f620-0209-4cd3-854d-51b0214d00de" xlink:to="loc_newt_UnvestedRestrictedStockMember_e34e03ff-dba2-4cb8-9c4b-b7e29a7c5795" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_e26c6be9-948b-4229-92b6-1a117740f64f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_7128a2b0-2014-4529-bc71-5f5176e78544" xlink:to="loc_us-gaap_StatementClassOfStockAxis_e26c6be9-948b-4229-92b6-1a117740f64f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_e26c6be9-948b-4229-92b6-1a117740f64f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_e26c6be9-948b-4229-92b6-1a117740f64f" xlink:to="loc_us-gaap_ClassOfStockDomain_e26c6be9-948b-4229-92b6-1a117740f64f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_2c2e8925-bb54-4323-8dc3-d972f8548040" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_e26c6be9-948b-4229-92b6-1a117740f64f" xlink:to="loc_us-gaap_ClassOfStockDomain_2c2e8925-bb54-4323-8dc3-d972f8548040" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SeriesAConvertiblePreferredStockMember_0a5045e9-0b50-48ef-9174-f0f6375efe36" xlink:href="newt-20241231.xsd#newt_SeriesAConvertiblePreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_2c2e8925-bb54-4323-8dc3-d972f8548040" xlink:to="loc_newt_SeriesAConvertiblePreferredStockMember_0a5045e9-0b50-48ef-9174-f0f6375efe36" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_ff963fbe-db4a-4674-83e4-7745098d4a0f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_7128a2b0-2014-4529-bc71-5f5176e78544" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_ff963fbe-db4a-4674-83e4-7745098d4a0f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_ff963fbe-db4a-4674-83e4-7745098d4a0f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_ff963fbe-db4a-4674-83e4-7745098d4a0f" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_ff963fbe-db4a-4674-83e4-7745098d4a0f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_48d6163d-7afb-4e71-83ee-67018ca1e5d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_ff963fbe-db4a-4674-83e4-7745098d4a0f" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_48d6163d-7afb-4e71-83ee-67018ca1e5d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_08fdc311-4e5a-41bc-bcc6-a9a8a1e7959b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_48d6163d-7afb-4e71-83ee-67018ca1e5d6" xlink:to="loc_us-gaap_SubsequentEventMember_08fdc311-4e5a-41bc-bcc6-a9a8a1e7959b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyDistributionToShareholdersPerShare_5df7827d-5bb1-4e66-b325-1abbb16fa97b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentCompanyDistributionToShareholdersPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_b6d14f1f-6c17-476d-9a71-0a41c9699d1a" xlink:to="loc_us-gaap_InvestmentCompanyDistributionToShareholdersPerShare_5df7827d-5bb1-4e66-b325-1abbb16fa97b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyDividendDistribution_6e2dd631-be35-42a2-917c-9400630a5cf3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentCompanyDividendDistribution"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_b6d14f1f-6c17-476d-9a71-0a41c9699d1a" xlink:to="loc_us-gaap_InvestmentCompanyDividendDistribution_6e2dd631-be35-42a2-917c-9400630a5cf3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan_8bf639d7-d988-48b9-9afd-8c88199fb2aa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_b6d14f1f-6c17-476d-9a71-0a41c9699d1a" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan_8bf639d7-d988-48b9-9afd-8c88199fb2aa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan_6cfe6702-db77-47ef-9af0-bcfa7374dfa5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_b6d14f1f-6c17-476d-9a71-0a41c9699d1a" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan_6cfe6702-db77-47ef-9af0-bcfa7374dfa5" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/REGULATORYCAPITALDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#REGULATORYCAPITALDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/REGULATORYCAPITALDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_436b20d5-e89f-4312-bb38-c6486d3e6a3f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_62ffbc12-8a2b-4358-8ffa-a1dc2f71d94f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_436b20d5-e89f-4312-bb38-c6486d3e6a3f" xlink:to="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_62ffbc12-8a2b-4358-8ffa-a1dc2f71d94f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_950dd8c2-0faf-4b9f-9d39-2bf14e75ab02" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_62ffbc12-8a2b-4358-8ffa-a1dc2f71d94f" xlink:to="loc_srt_ConsolidatedEntitiesAxis_950dd8c2-0faf-4b9f-9d39-2bf14e75ab02" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_950dd8c2-0faf-4b9f-9d39-2bf14e75ab02_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_950dd8c2-0faf-4b9f-9d39-2bf14e75ab02" xlink:to="loc_srt_ConsolidatedEntitiesDomain_950dd8c2-0faf-4b9f-9d39-2bf14e75ab02_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_3d1fde80-eb63-4a05-b331-b1b764ea6e6e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_950dd8c2-0faf-4b9f-9d39-2bf14e75ab02" xlink:to="loc_srt_ConsolidatedEntitiesDomain_3d1fde80-eb63-4a05-b331-b1b764ea6e6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NewtekBankMember_1d592dda-ea1d-4d49-a6c8-90aa2592cd3b" xlink:href="newt-20241231.xsd#newt_NewtekBankMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_3d1fde80-eb63-4a05-b331-b1b764ea6e6e" xlink:to="loc_newt_NewtekBankMember_1d592dda-ea1d-4d49-a6c8-90aa2592cd3b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalAbstract_413bec4e-2304-4a78-9b5c-447f0067cb6a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneRiskBasedCapitalAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_436b20d5-e89f-4312-bb38-c6486d3e6a3f" xlink:to="loc_us-gaap_TierOneRiskBasedCapitalAbstract_413bec4e-2304-4a78-9b5c-447f0067cb6a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapital_eb347d06-c915-464f-9b66-037a3fda62db" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneLeverageCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneRiskBasedCapitalAbstract_413bec4e-2304-4a78-9b5c-447f0067cb6a" xlink:to="loc_us-gaap_TierOneLeverageCapital_eb347d06-c915-464f-9b66-037a3fda62db" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalToAverageAssets_f4c38938-bb40-44b4-b95a-de27fb0ae472" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneLeverageCapitalToAverageAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneRiskBasedCapitalAbstract_413bec4e-2304-4a78-9b5c-447f0067cb6a" xlink:to="loc_us-gaap_TierOneLeverageCapitalToAverageAssets_f4c38938-bb40-44b4-b95a-de27fb0ae472" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacy_ebb97a17-ff86-41fc-acf9-fa869089be71" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacy"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneRiskBasedCapitalAbstract_413bec4e-2304-4a78-9b5c-447f0067cb6a" xlink:to="loc_us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacy_ebb97a17-ff86-41fc-acf9-fa869089be71" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets_22ff8cd1-9661-463a-9d0d-8e0820984b8c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneRiskBasedCapitalAbstract_413bec4e-2304-4a78-9b5c-447f0067cb6a" xlink:to="loc_us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets_22ff8cd1-9661-463a-9d0d-8e0820984b8c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized_e80bdcd8-3a4f-444f-97c6-b6defc8e2551" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneRiskBasedCapitalAbstract_413bec4e-2304-4a78-9b5c-447f0067cb6a" xlink:to="loc_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized_e80bdcd8-3a4f-444f-97c6-b6defc8e2551" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets_445e78b2-c73b-4b7c-9b3a-647c3e0347b2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneRiskBasedCapitalAbstract_413bec4e-2304-4a78-9b5c-447f0067cb6a" xlink:to="loc_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets_445e78b2-c73b-4b7c-9b3a-647c3e0347b2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonEquityTierOneCapitalAbstract_3010ea33-1a50-4095-ad3f-b8c7484015be" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonEquityTierOneCapitalAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_436b20d5-e89f-4312-bb38-c6486d3e6a3f" xlink:to="loc_us-gaap_CommonEquityTierOneCapitalAbstract_3010ea33-1a50-4095-ad3f-b8c7484015be" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonEquityTierOneCapital_5218d09f-884f-4594-8690-06b91ff34b2b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonEquityTierOneCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CommonEquityTierOneCapitalAbstract_3010ea33-1a50-4095-ad3f-b8c7484015be" xlink:to="loc_us-gaap_CommonEquityTierOneCapital_5218d09f-884f-4594-8690-06b91ff34b2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonEquityTierOneCapitalRatio_d099a5dc-02e4-478e-8d4d-c18b85f75630" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonEquityTierOneCapitalRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CommonEquityTierOneCapitalAbstract_3010ea33-1a50-4095-ad3f-b8c7484015be" xlink:to="loc_us-gaap_CommonEquityTierOneCapitalRatio_d099a5dc-02e4-478e-8d4d-c18b85f75630" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonEquityTierOneCapitalRequiredForCapitalAdequacy_1f340177-89fb-43c8-bf22-223853fd9401" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonEquityTierOneCapitalRequiredForCapitalAdequacy"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CommonEquityTierOneCapitalAbstract_3010ea33-1a50-4095-ad3f-b8c7484015be" xlink:to="loc_us-gaap_CommonEquityTierOneCapitalRequiredForCapitalAdequacy_1f340177-89fb-43c8-bf22-223853fd9401" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioCapitalAdequacyMinimum_acf0f1ac-7f83-40a6-838e-3b834265a1fe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioCapitalAdequacyMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CommonEquityTierOneCapitalAbstract_3010ea33-1a50-4095-ad3f-b8c7484015be" xlink:to="loc_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioCapitalAdequacyMinimum_acf0f1ac-7f83-40a6-838e-3b834265a1fe" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized_68ab7818-9f41-4129-8461-b4e57025cbb2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CommonEquityTierOneCapitalAbstract_3010ea33-1a50-4095-ad3f-b8c7484015be" xlink:to="loc_us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized_68ab7818-9f41-4129-8461-b4e57025cbb2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum_baf25f8f-56a1-4691-8419-1c3398af1f28" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CommonEquityTierOneCapitalAbstract_3010ea33-1a50-4095-ad3f-b8c7484015be" xlink:to="loc_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum_baf25f8f-56a1-4691-8419-1c3398af1f28" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalAbstract_cd20cf3f-ca0a-4580-a7f0-33d2a79dba7a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneLeverageCapitalAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_436b20d5-e89f-4312-bb38-c6486d3e6a3f" xlink:to="loc_us-gaap_TierOneLeverageCapitalAbstract_cd20cf3f-ca0a-4580-a7f0-33d2a79dba7a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapital_b9016cb7-3389-4f2a-85ef-e9f4740aed5a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneRiskBasedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneLeverageCapitalAbstract_cd20cf3f-ca0a-4580-a7f0-33d2a79dba7a" xlink:to="loc_us-gaap_TierOneRiskBasedCapital_b9016cb7-3389-4f2a-85ef-e9f4740aed5a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets_b14ea50c-ff15-4046-ac49-203118947d81" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneLeverageCapitalAbstract_cd20cf3f-ca0a-4580-a7f0-33d2a79dba7a" xlink:to="loc_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets_b14ea50c-ff15-4046-ac49-203118947d81" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacy_2d99528b-2c17-44c2-94d0-ae8cbf36b065" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacy"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneLeverageCapitalAbstract_cd20cf3f-ca0a-4580-a7f0-33d2a79dba7a" xlink:to="loc_us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacy_2d99528b-2c17-44c2-94d0-ae8cbf36b065" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets_b9610cda-7fd2-4f11-bddb-c64d92aff935" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneLeverageCapitalAbstract_cd20cf3f-ca0a-4580-a7f0-33d2a79dba7a" xlink:to="loc_us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets_b9610cda-7fd2-4f11-bddb-c64d92aff935" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized_20fb0ff5-6a14-49a0-84d3-160ddfc623bb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneLeverageCapitalAbstract_cd20cf3f-ca0a-4580-a7f0-33d2a79dba7a" xlink:to="loc_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized_20fb0ff5-6a14-49a0-84d3-160ddfc623bb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets_f82de3d1-28c9-4743-9207-308839bf4b9f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TierOneLeverageCapitalAbstract_cd20cf3f-ca0a-4580-a7f0-33d2a79dba7a" xlink:to="loc_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets_f82de3d1-28c9-4743-9207-308839bf4b9f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalAbstract_7c58b57e-0769-48a0-aa62-8be6a8dda76b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CapitalAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_436b20d5-e89f-4312-bb38-c6486d3e6a3f" xlink:to="loc_us-gaap_CapitalAbstract_7c58b57e-0769-48a0-aa62-8be6a8dda76b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Capital_12f3a7f3-c35b-410a-9f3f-bfec1aacf00a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Capital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalAbstract_7c58b57e-0769-48a0-aa62-8be6a8dda76b" xlink:to="loc_us-gaap_Capital_12f3a7f3-c35b-410a-9f3f-bfec1aacf00a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalToRiskWeightedAssets_4fb0ca92-160d-4536-a7e9-02c38ff31cae" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CapitalToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalAbstract_7c58b57e-0769-48a0-aa62-8be6a8dda76b" xlink:to="loc_us-gaap_CapitalToRiskWeightedAssets_4fb0ca92-160d-4536-a7e9-02c38ff31cae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalRequiredForCapitalAdequacy_60f670b0-13f3-4e48-9964-55cce683bc6a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CapitalRequiredForCapitalAdequacy"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalAbstract_7c58b57e-0769-48a0-aa62-8be6a8dda76b" xlink:to="loc_us-gaap_CapitalRequiredForCapitalAdequacy_60f670b0-13f3-4e48-9964-55cce683bc6a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets_a4da3f16-74f1-4fac-be10-e71bfaf3dfc9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalAbstract_7c58b57e-0769-48a0-aa62-8be6a8dda76b" xlink:to="loc_us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets_a4da3f16-74f1-4fac-be10-e71bfaf3dfc9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalRequiredToBeWellCapitalized_c8b6a382-1ac0-4761-8005-bc69c4f724ac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CapitalRequiredToBeWellCapitalized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalAbstract_7c58b57e-0769-48a0-aa62-8be6a8dda76b" xlink:to="loc_us-gaap_CapitalRequiredToBeWellCapitalized_c8b6a382-1ac0-4761-8005-bc69c4f724ac" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets_07fbf869-e401-44eb-b857-94ec8415e53d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalAbstract_7c58b57e-0769-48a0-aa62-8be6a8dda76b" xlink:to="loc_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets_07fbf869-e401-44eb-b857-94ec8415e53d" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BENEFITPLANSNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BENEFITPLANSNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BENEFITPLANSNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_06cfaa43-6deb-4107-a837-bde037b15a2e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_01bb10fa-553f-4ff8-ae58-c8665725a775" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_06cfaa43-6deb-4107-a837-bde037b15a2e" xlink:to="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_01bb10fa-553f-4ff8-ae58-c8665725a775" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_8379e15e-6e0b-45c8-b9f1-ea9578911192" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_01bb10fa-553f-4ff8-ae58-c8665725a775" xlink:to="loc_us-gaap_PlanNameAxis_8379e15e-6e0b-45c8-b9f1-ea9578911192" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_8379e15e-6e0b-45c8-b9f1-ea9578911192_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_8379e15e-6e0b-45c8-b9f1-ea9578911192" xlink:to="loc_us-gaap_PlanNameDomain_8379e15e-6e0b-45c8-b9f1-ea9578911192_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_d04b696b-2c7a-46c1-96f4-3515ecd5417a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_8379e15e-6e0b-45c8-b9f1-ea9578911192" xlink:to="loc_us-gaap_PlanNameDomain_d04b696b-2c7a-46c1-96f4-3515ecd5417a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_EmployeeStockPurchasePlanMember_8454efaf-e748-4473-b840-688d1e78dbd7" xlink:href="newt-20241231.xsd#newt_EmployeeStockPurchasePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_d04b696b-2c7a-46c1-96f4-3515ecd5417a" xlink:to="loc_newt_EmployeeStockPurchasePlanMember_8454efaf-e748-4473-b840-688d1e78dbd7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_44cf9f98-fe87-4caf-bf79-a4abd4ad853e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_06cfaa43-6deb-4107-a837-bde037b15a2e" xlink:to="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_44cf9f98-fe87-4caf-bf79-a4abd4ad853e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DefinedContributionPlanEmployerMatchingContributionPercentOfMatchOfEmployeeContributions_038018bb-e2ab-4b62-85bd-13018589e1b3" xlink:href="newt-20241231.xsd#newt_DefinedContributionPlanEmployerMatchingContributionPercentOfMatchOfEmployeeContributions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_06cfaa43-6deb-4107-a837-bde037b15a2e" xlink:to="loc_newt_DefinedContributionPlanEmployerMatchingContributionPercentOfMatchOfEmployeeContributions_038018bb-e2ab-4b62-85bd-13018589e1b3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount_d1261d62-8397-43da-b956-c73ba27138f2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_06cfaa43-6deb-4107-a837-bde037b15a2e" xlink:to="loc_us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount_d1261d62-8397-43da-b956-c73ba27138f2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_7efa125c-dedf-4b02-bb3e-74bface72ff4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_06cfaa43-6deb-4107-a837-bde037b15a2e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_7efa125c-dedf-4b02-bb3e-74bface72ff4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate_6dde82cf-9509-49df-8926-e86b25c75322" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_06cfaa43-6deb-4107-a837-bde037b15a2e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate_6dde82cf-9509-49df-8926-e86b25c75322" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumFairValueOfSharesToBePurchased_719f0eda-d032-4785-82c3-e0d2e587b14d" xlink:href="newt-20241231.xsd#newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumFairValueOfSharesToBePurchased"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_06cfaa43-6deb-4107-a837-bde037b15a2e" xlink:to="loc_newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumFairValueOfSharesToBePurchased_719f0eda-d032-4785-82c3-e0d2e587b14d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent_399ad603-4854-41b6-95da-a9d26ccd6d2c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_06cfaa43-6deb-4107-a837-bde037b15a2e" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent_399ad603-4854-41b6-95da-a9d26ccd6d2c" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BENEFITPLANSRestrictedStockActivityDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BENEFITPLANSRestrictedStockActivityDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BENEFITPLANSRestrictedStockActivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_3c1e4d77-631d-452a-a1a2-d1d442d2b326" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_ed9c8d20-4565-4101-9215-ffe256f996e7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_3c1e4d77-631d-452a-a1a2-d1d442d2b326" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_ed9c8d20-4565-4101-9215-ffe256f996e7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_fab6627b-2ed7-44ce-8ead-f2117c02ff82" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_ed9c8d20-4565-4101-9215-ffe256f996e7" xlink:to="loc_us-gaap_AwardTypeAxis_fab6627b-2ed7-44ce-8ead-f2117c02ff82" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fab6627b-2ed7-44ce-8ead-f2117c02ff82_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_fab6627b-2ed7-44ce-8ead-f2117c02ff82" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fab6627b-2ed7-44ce-8ead-f2117c02ff82_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_566187e4-071c-49dc-a005-3745ffdf985d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_fab6627b-2ed7-44ce-8ead-f2117c02ff82" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_566187e4-071c-49dc-a005-3745ffdf985d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_768f7bd9-0916-4414-b6a6-f9bf53477b98" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_566187e4-071c-49dc-a005-3745ffdf985d" xlink:to="loc_us-gaap_RestrictedStockMember_768f7bd9-0916-4414-b6a6-f9bf53477b98" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_848cf40e-7c75-449e-8111-aa8e943e70be" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_ed9c8d20-4565-4101-9215-ffe256f996e7" xlink:to="loc_us-gaap_PlanNameAxis_848cf40e-7c75-449e-8111-aa8e943e70be" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_848cf40e-7c75-449e-8111-aa8e943e70be_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_848cf40e-7c75-449e-8111-aa8e943e70be" xlink:to="loc_us-gaap_PlanNameDomain_848cf40e-7c75-449e-8111-aa8e943e70be_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_b584d0bf-f443-44d6-9710-d6a20258ecaa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_848cf40e-7c75-449e-8111-aa8e943e70be" xlink:to="loc_us-gaap_PlanNameDomain_b584d0bf-f443-44d6-9710-d6a20258ecaa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2023And2015StockIncentivePlanMember_c28e4a2d-54a5-4d27-b910-7733ad4756d1" xlink:href="newt-20241231.xsd#newt_A2023And2015StockIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_b584d0bf-f443-44d6-9710-d6a20258ecaa" xlink:to="loc_newt_A2023And2015StockIncentivePlanMember_c28e4a2d-54a5-4d27-b910-7733ad4756d1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2023StockIncentivePlanMember_41a4281b-4380-4a8c-af19-feb72cc8615c" xlink:href="newt-20241231.xsd#newt_A2023StockIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_A2023And2015StockIncentivePlanMember_c28e4a2d-54a5-4d27-b910-7733ad4756d1" xlink:to="loc_newt_A2023StockIncentivePlanMember_41a4281b-4380-4a8c-af19-feb72cc8615c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_A2015EquityIncentivePlanMember_c1900a5a-a10c-4a65-bb98-8b5c531c9518" xlink:href="newt-20241231.xsd#newt_A2015EquityIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_A2023And2015StockIncentivePlanMember_c28e4a2d-54a5-4d27-b910-7733ad4756d1" xlink:to="loc_newt_A2015EquityIncentivePlanMember_c1900a5a-a10c-4a65-bb98-8b5c531c9518" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_0a2b3df0-5680-46e2-9d7d-4cebda871475" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_ed9c8d20-4565-4101-9215-ffe256f996e7" xlink:to="loc_srt_RangeAxis_0a2b3df0-5680-46e2-9d7d-4cebda871475" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_0a2b3df0-5680-46e2-9d7d-4cebda871475_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_0a2b3df0-5680-46e2-9d7d-4cebda871475" xlink:to="loc_srt_RangeMember_0a2b3df0-5680-46e2-9d7d-4cebda871475_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_b1488c2f-40a5-4b63-9a1d-760bdaa6ab10" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_0a2b3df0-5680-46e2-9d7d-4cebda871475" xlink:to="loc_srt_RangeMember_b1488c2f-40a5-4b63-9a1d-760bdaa6ab10" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_119a8deb-a40e-4bfb-9600-e9d87195f1f1" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_b1488c2f-40a5-4b63-9a1d-760bdaa6ab10" xlink:to="loc_srt_MinimumMember_119a8deb-a40e-4bfb-9600-e9d87195f1f1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_85ee5c38-2fa8-4d8a-a08f-00221853acb0" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_b1488c2f-40a5-4b63-9a1d-760bdaa6ab10" xlink:to="loc_srt_MaximumMember_85ee5c38-2fa8-4d8a-a08f-00221853acb0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_0d5d6660-7479-4455-b13e-44748a624141" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_3c1e4d77-631d-452a-a1a2-d1d442d2b326" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_0d5d6660-7479-4455-b13e-44748a624141" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsNetOfForfeituresInPeriod_bd8c89c4-fa1e-4f3f-92fe-e391f1d4ebb8" xlink:href="newt-20241231.xsd#newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsNetOfForfeituresInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_3c1e4d77-631d-452a-a1a2-d1d442d2b326" xlink:to="loc_newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsNetOfForfeituresInPeriod_bd8c89c4-fa1e-4f3f-92fe-e391f1d4ebb8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_34099f2f-c69f-459b-9b0b-6ac683fc7f91" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_3c1e4d77-631d-452a-a1a2-d1d442d2b326" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_34099f2f-c69f-459b-9b0b-6ac683fc7f91" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_60166e75-c0bc-4f1e-879f-14925707637c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_3c1e4d77-631d-452a-a1a2-d1d442d2b326" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_60166e75-c0bc-4f1e-879f-14925707637c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_36dccf6a-2b75-4952-a012-cb24ecff92ac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_3c1e4d77-631d-452a-a1a2-d1d442d2b326" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_36dccf6a-2b75-4952-a012-cb24ecff92ac" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BENEFITPLANSSharesOutstandingDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BENEFITPLANSSharesOutstandingDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BENEFITPLANSSharesOutstandingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_08ebdab5-8e5b-443a-ae7c-fb8071537fbc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_4855ab29-f36b-4b71-856e-9b0cb1423a80" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_08ebdab5-8e5b-443a-ae7c-fb8071537fbc" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_4855ab29-f36b-4b71-856e-9b0cb1423a80" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_09943aef-3534-41fd-b47c-9c51da4d4a53" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_4855ab29-f36b-4b71-856e-9b0cb1423a80" xlink:to="loc_us-gaap_AwardTypeAxis_09943aef-3534-41fd-b47c-9c51da4d4a53" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_09943aef-3534-41fd-b47c-9c51da4d4a53_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_09943aef-3534-41fd-b47c-9c51da4d4a53" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_09943aef-3534-41fd-b47c-9c51da4d4a53_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bea68005-79c1-4276-90de-a88a9a8f13ab" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_09943aef-3534-41fd-b47c-9c51da4d4a53" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bea68005-79c1-4276-90de-a88a9a8f13ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_6c621fcb-2930-4958-ac56-41bd078c79cb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bea68005-79c1-4276-90de-a88a9a8f13ab" xlink:to="loc_us-gaap_RestrictedStockMember_6c621fcb-2930-4958-ac56-41bd078c79cb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_UnvestedRestrictedStockMember_86936f7d-5df9-491f-8887-fea346f9bcd0" xlink:href="newt-20241231.xsd#newt_UnvestedRestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bea68005-79c1-4276-90de-a88a9a8f13ab" xlink:to="loc_newt_UnvestedRestrictedStockMember_86936f7d-5df9-491f-8887-fea346f9bcd0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_bf0a9d60-ffe1-4fc8-a372-4610043c6376" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_08ebdab5-8e5b-443a-ae7c-fb8071537fbc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_bf0a9d60-ffe1-4fc8-a372-4610043c6376" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_380e9b7f-5000-4e0d-8afc-73b27594a4fb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_08ebdab5-8e5b-443a-ae7c-fb8071537fbc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_380e9b7f-5000-4e0d-8afc-73b27594a4fb" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BENEFITPLANSUnrecognizedCompensationDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BENEFITPLANSUnrecognizedCompensationDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BENEFITPLANSUnrecognizedCompensationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_d61a7bc8-b958-4619-b795-115fb2a77dc3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_15bbc7d9-3ee8-4dbd-b503-b898df3bba97" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_d61a7bc8-b958-4619-b795-115fb2a77dc3" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_15bbc7d9-3ee8-4dbd-b503-b898df3bba97" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_96b4e1c3-8583-4965-b5dd-9ca6ee106949" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_15bbc7d9-3ee8-4dbd-b503-b898df3bba97" xlink:to="loc_us-gaap_AwardTypeAxis_96b4e1c3-8583-4965-b5dd-9ca6ee106949" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_96b4e1c3-8583-4965-b5dd-9ca6ee106949_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_96b4e1c3-8583-4965-b5dd-9ca6ee106949" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_96b4e1c3-8583-4965-b5dd-9ca6ee106949_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_66b82863-3ebd-470e-bd01-57227795896c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_96b4e1c3-8583-4965-b5dd-9ca6ee106949" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_66b82863-3ebd-470e-bd01-57227795896c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_d9efb318-d14b-4cc7-8159-43e8bfe39db7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_66b82863-3ebd-470e-bd01-57227795896c" xlink:to="loc_us-gaap_RestrictedStockMember_d9efb318-d14b-4cc7-8159-43e8bfe39db7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_1d9b715c-6f0e-427b-83ce-00c754df407b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_d61a7bc8-b958-4619-b795-115fb2a77dc3" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_1d9b715c-6f0e-427b-83ce-00c754df407b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_5c7a4965-b3b5-43c7-9162-d0db36c22106" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_d61a7bc8-b958-4619-b795-115fb2a77dc3" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_5c7a4965-b3b5-43c7-9162-d0db36c22106" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BENEFITPLANSESPPInformationDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BENEFITPLANSESPPInformationDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BENEFITPLANSESPPInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_26e27fd8-1fab-474f-bd73-949af17a8f2a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_5cd78502-7f4f-4101-b61a-2a94e61ee423" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_26e27fd8-1fab-474f-bd73-949af17a8f2a" xlink:to="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_5cd78502-7f4f-4101-b61a-2a94e61ee423" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_b2c354cd-6815-413b-a68f-ab2a39255d9b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_5cd78502-7f4f-4101-b61a-2a94e61ee423" xlink:to="loc_us-gaap_PlanNameAxis_b2c354cd-6815-413b-a68f-ab2a39255d9b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_b2c354cd-6815-413b-a68f-ab2a39255d9b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_b2c354cd-6815-413b-a68f-ab2a39255d9b" xlink:to="loc_us-gaap_PlanNameDomain_b2c354cd-6815-413b-a68f-ab2a39255d9b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_6f723594-0408-472f-9ecd-66471232b093" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_b2c354cd-6815-413b-a68f-ab2a39255d9b" xlink:to="loc_us-gaap_PlanNameDomain_6f723594-0408-472f-9ecd-66471232b093" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_EmployeeStockPurchasePlanMember_14cbb2a4-b2fa-483b-8464-b42655b0e1d4" xlink:href="newt-20241231.xsd#newt_EmployeeStockPurchasePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_6f723594-0408-472f-9ecd-66471232b093" xlink:to="loc_newt_EmployeeStockPurchasePlanMember_14cbb2a4-b2fa-483b-8464-b42655b0e1d4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesPurchasedForAward_4e8141b3-2f00-4443-8a72-a6f407c91091" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesPurchasedForAward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_26e27fd8-1fab-474f-bd73-949af17a8f2a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesPurchasedForAward_4e8141b3-2f00-4443-8a72-a6f407c91091" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased_17d100c3-1a8f-4cf5-89be-269180b73735" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_26e27fd8-1fab-474f-bd73-949af17a8f2a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased_17d100c3-1a8f-4cf5-89be-269180b73735" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardValuePurchasedForAward_9534f5a3-bb9c-4c76-940a-440cc662a367" xlink:href="newt-20241231.xsd#newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardValuePurchasedForAward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_26e27fd8-1fab-474f-bd73-949af17a8f2a" xlink:to="loc_newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardValuePurchasedForAward_9534f5a3-bb9c-4c76-940a-440cc662a367" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BENEFITPLANSESPPActivityDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BENEFITPLANSESPPActivityDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BENEFITPLANSESPPActivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_c1568d39-11e3-4864-bced-ac6e087e962f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_5294a719-8572-4f3e-8ca5-a21211c3d004" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_c1568d39-11e3-4864-bced-ac6e087e962f" xlink:to="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_5294a719-8572-4f3e-8ca5-a21211c3d004" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_c57f5cad-1c11-4463-b0ce-e3bcf572f826" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_5294a719-8572-4f3e-8ca5-a21211c3d004" xlink:to="loc_us-gaap_PlanNameAxis_c57f5cad-1c11-4463-b0ce-e3bcf572f826" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_c57f5cad-1c11-4463-b0ce-e3bcf572f826_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_c57f5cad-1c11-4463-b0ce-e3bcf572f826" xlink:to="loc_us-gaap_PlanNameDomain_c57f5cad-1c11-4463-b0ce-e3bcf572f826_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_32b086fc-1a55-40d9-b304-c60eecf016c6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_c57f5cad-1c11-4463-b0ce-e3bcf572f826" xlink:to="loc_us-gaap_PlanNameDomain_32b086fc-1a55-40d9-b304-c60eecf016c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_EmployeeStockPurchasePlanMember_844953c7-0d91-46ca-9728-7e8f1cd17785" xlink:href="newt-20241231.xsd#newt_EmployeeStockPurchasePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_32b086fc-1a55-40d9-b304-c60eecf016c6" xlink:to="loc_newt_EmployeeStockPurchasePlanMember_844953c7-0d91-46ca-9728-7e8f1cd17785" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForFutureIssuanceRollForward_3686d2a3-b5d0-4163-b640-2edc958a7d0f" xlink:href="newt-20241231.xsd#newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForFutureIssuanceRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_c1568d39-11e3-4864-bced-ac6e087e962f" xlink:to="loc_newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForFutureIssuanceRollForward_3686d2a3-b5d0-4163-b640-2edc958a7d0f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_28069237-db0d-40ce-8e1d-57118da4ffac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForFutureIssuanceRollForward_3686d2a3-b5d0-4163-b640-2edc958a7d0f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_28069237-db0d-40ce-8e1d-57118da4ffac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesPurchasedForAward_09f0ff25-45aa-4dac-867e-e45a1f70d6e6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesPurchasedForAward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_newt_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForFutureIssuanceRollForward_3686d2a3-b5d0-4163-b640-2edc958a7d0f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesPurchasedForAward_09f0ff25-45aa-4dac-867e-e45a1f70d6e6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_817b14cd-1551-4e98-843f-4f836baeb093" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/BENEFITPLANSCompensationExpenseDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#BENEFITPLANSCompensationExpenseDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/BENEFITPLANSCompensationExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_5f38affd-0a9d-4c3a-8645-2bce559da028" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_5fe24b23-688c-4cf5-bf28-561cfd0844ff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_5f38affd-0a9d-4c3a-8645-2bce559da028" xlink:to="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_5fe24b23-688c-4cf5-bf28-561cfd0844ff" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_51499ec8-c9da-4bec-b13f-9e51a5b69bdd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_5fe24b23-688c-4cf5-bf28-561cfd0844ff" xlink:to="loc_us-gaap_AwardTypeAxis_51499ec8-c9da-4bec-b13f-9e51a5b69bdd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_51499ec8-c9da-4bec-b13f-9e51a5b69bdd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_51499ec8-c9da-4bec-b13f-9e51a5b69bdd" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_51499ec8-c9da-4bec-b13f-9e51a5b69bdd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_299d8a9e-421a-4aec-baa4-98d5383069ca" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_51499ec8-c9da-4bec-b13f-9e51a5b69bdd" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_299d8a9e-421a-4aec-baa4-98d5383069ca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_477f709b-24c3-45ed-b358-31be50cbe665" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_299d8a9e-421a-4aec-baa4-98d5383069ca" xlink:to="loc_us-gaap_RestrictedStockMember_477f709b-24c3-45ed-b358-31be50cbe665" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_853f11f6-0e0d-491b-86a5-9c8d8379d5c4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_5fe24b23-688c-4cf5-bf28-561cfd0844ff" xlink:to="loc_us-gaap_PlanNameAxis_853f11f6-0e0d-491b-86a5-9c8d8379d5c4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_853f11f6-0e0d-491b-86a5-9c8d8379d5c4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_853f11f6-0e0d-491b-86a5-9c8d8379d5c4" xlink:to="loc_us-gaap_PlanNameDomain_853f11f6-0e0d-491b-86a5-9c8d8379d5c4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_bd43fc1e-57fb-41f6-b9a8-7ea9427fc6c9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_853f11f6-0e0d-491b-86a5-9c8d8379d5c4" xlink:to="loc_us-gaap_PlanNameDomain_bd43fc1e-57fb-41f6-b9a8-7ea9427fc6c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_EmployeeStockPurchasePlanMember_72c175e8-f3a4-476e-894d-067de15f5756" xlink:href="newt-20241231.xsd#newt_EmployeeStockPurchasePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_bd43fc1e-57fb-41f6-b9a8-7ea9427fc6c9" xlink:to="loc_newt_EmployeeStockPurchasePlanMember_72c175e8-f3a4-476e-894d-067de15f5756" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_75452d3e-0ddc-4b51-ac59-94a03e2d4282" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_5f38affd-0a9d-4c3a-8645-2bce559da028" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_75452d3e-0ddc-4b51-ac59-94a03e2d4282" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/INCOMETAXESNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#INCOMETAXESNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/INCOMETAXESNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsOwnedFederalIncomeTaxNoteLineItems_21aadddd-44eb-43c3-9c61-e32986d6d9d8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentsOwnedFederalIncomeTaxNoteLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalIncomeTaxNoteTable_a6607ff6-203a-47ff-926b-5cd58516810a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FederalIncomeTaxNoteTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_InvestmentsOwnedFederalIncomeTaxNoteLineItems_21aadddd-44eb-43c3-9c61-e32986d6d9d8" xlink:to="loc_us-gaap_FederalIncomeTaxNoteTable_a6607ff6-203a-47ff-926b-5cd58516810a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodAxis_d7e67d1a-3bd5-4fdc-becc-97ce332de1bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TaxPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FederalIncomeTaxNoteTable_a6607ff6-203a-47ff-926b-5cd58516810a" xlink:to="loc_us-gaap_TaxPeriodAxis_d7e67d1a-3bd5-4fdc-becc-97ce332de1bc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_d7e67d1a-3bd5-4fdc-becc-97ce332de1bc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TaxPeriodAxis_d7e67d1a-3bd5-4fdc-becc-97ce332de1bc" xlink:to="loc_us-gaap_TaxPeriodDomain_d7e67d1a-3bd5-4fdc-becc-97ce332de1bc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_d3ad84d7-86c9-4dfd-a191-4adfebda1d66" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TaxPeriodAxis_d7e67d1a-3bd5-4fdc-becc-97ce332de1bc" xlink:to="loc_us-gaap_TaxPeriodDomain_d3ad84d7-86c9-4dfd-a191-4adfebda1d66" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_FutureTaxablePeriodsMember_5adc1c9d-a742-4bc9-8376-ce3a1316dc57" xlink:href="newt-20241231.xsd#newt_FutureTaxablePeriodsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxPeriodDomain_d3ad84d7-86c9-4dfd-a191-4adfebda1d66" xlink:to="loc_newt_FutureTaxablePeriodsMember_5adc1c9d-a742-4bc9-8376-ce3a1316dc57" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_TaxYears2029Through2037Member_65511d52-42cd-40a8-a115-a4d26366a3d9" xlink:href="newt-20241231.xsd#newt_TaxYears2029Through2037Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxPeriodDomain_d3ad84d7-86c9-4dfd-a191-4adfebda1d66" xlink:to="loc_newt_TaxYears2029Through2037Member_65511d52-42cd-40a8-a115-a4d26366a3d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_857dcdb7-9766-4a8d-9834-69215ad8d3bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsOwnedFederalIncomeTaxNoteLineItems_21aadddd-44eb-43c3-9c61-e32986d6d9d8" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_857dcdb7-9766-4a8d-9834-69215ad8d3bc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLossCarryforwards_3200f443-4cd3-41c2-9a04-17d9986dff88" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingLossCarryforwards"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsOwnedFederalIncomeTaxNoteLineItems_21aadddd-44eb-43c3-9c61-e32986d6d9d8" xlink:to="loc_us-gaap_OperatingLossCarryforwards_3200f443-4cd3-41c2-9a04-17d9986dff88" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/SEGMENTSDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#SEGMENTSDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/SEGMENTSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_e6c7d723-42dc-4201-8dfd-7a1c7e70b347" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_e6c7d723-42dc-4201-8dfd-7a1c7e70b347" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_6387863c-0142-4acb-b202-c5521364d11b" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_e6c7d723-42dc-4201-8dfd-7a1c7e70b347" xlink:to="loc_srt_ConsolidationItemsAxis_6387863c-0142-4acb-b202-c5521364d11b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_6387863c-0142-4acb-b202-c5521364d11b_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_6387863c-0142-4acb-b202-c5521364d11b" xlink:to="loc_srt_ConsolidationItemsDomain_6387863c-0142-4acb-b202-c5521364d11b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_48e945cf-a59e-493c-8618-34cc8f2de987" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_6387863c-0142-4acb-b202-c5521364d11b" xlink:to="loc_srt_ConsolidationItemsDomain_48e945cf-a59e-493c-8618-34cc8f2de987" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_c62a880f-c560-4ef1-bc19-6e45d75faa30" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_48e945cf-a59e-493c-8618-34cc8f2de987" xlink:to="loc_us-gaap_OperatingSegmentsMember_c62a880f-c560-4ef1-bc19-6e45d75faa30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_f313d693-11c6-40e5-bdf8-4d1f107f2671" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_48e945cf-a59e-493c-8618-34cc8f2de987" xlink:to="loc_us-gaap_IntersegmentEliminationMember_f313d693-11c6-40e5-bdf8-4d1f107f2671" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_b7d0adbd-8546-4b45-924d-47850758966a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_48e945cf-a59e-493c-8618-34cc8f2de987" xlink:to="loc_us-gaap_CorporateNonSegmentMember_b7d0adbd-8546-4b45-924d-47850758966a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_5d0f0504-6327-4352-a70f-d59e1f4c56d7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_e6c7d723-42dc-4201-8dfd-7a1c7e70b347" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_5d0f0504-6327-4352-a70f-d59e1f4c56d7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_5d0f0504-6327-4352-a70f-d59e1f4c56d7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_5d0f0504-6327-4352-a70f-d59e1f4c56d7" xlink:to="loc_us-gaap_SegmentDomain_5d0f0504-6327-4352-a70f-d59e1f4c56d7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_9acfc63d-796f-4c22-839b-db21b7457f56" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_5d0f0504-6327-4352-a70f-d59e1f4c56d7" xlink:to="loc_us-gaap_SegmentDomain_9acfc63d-796f-4c22-839b-db21b7457f56" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_BankingSegmentMember_30fc0232-4cf4-46a0-8410-43a3a9c20e16" xlink:href="newt-20241231.xsd#newt_BankingSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_9acfc63d-796f-4c22-839b-db21b7457f56" xlink:to="loc_newt_BankingSegmentMember_30fc0232-4cf4-46a0-8410-43a3a9c20e16" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_AlternativeLendingMember_cf204975-5b53-4731-88fa-fbc17a4b891b" xlink:href="newt-20241231.xsd#newt_AlternativeLendingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_9acfc63d-796f-4c22-839b-db21b7457f56" xlink:to="loc_newt_AlternativeLendingMember_cf204975-5b53-4731-88fa-fbc17a4b891b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_TechnologyMember_192c0dd1-5cd6-4540-92f8-6f3d28a2a151" xlink:href="newt-20241231.xsd#newt_TechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_9acfc63d-796f-4c22-839b-db21b7457f56" xlink:to="loc_newt_TechnologyMember_192c0dd1-5cd6-4540-92f8-6f3d28a2a151" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NSBFMember_2af7a06f-4552-44c3-b998-23c365508f42" xlink:href="newt-20241231.xsd#newt_NSBFMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_9acfc63d-796f-4c22-839b-db21b7457f56" xlink:to="loc_newt_NSBFMember_2af7a06f-4552-44c3-b998-23c365508f42" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_PaymentsMember_93804c86-83bc-4119-89e7-b967ece54800" xlink:href="newt-20241231.xsd#newt_PaymentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_9acfc63d-796f-4c22-839b-db21b7457f56" xlink:to="loc_newt_PaymentsMember_93804c86-83bc-4119-89e7-b967ece54800" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_c59293c8-d8df-4000-92e0-fae3a7c6da64" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_e6c7d723-42dc-4201-8dfd-7a1c7e70b347" xlink:to="loc_srt_RangeAxis_c59293c8-d8df-4000-92e0-fae3a7c6da64" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_c59293c8-d8df-4000-92e0-fae3a7c6da64_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_c59293c8-d8df-4000-92e0-fae3a7c6da64" xlink:to="loc_srt_RangeMember_c59293c8-d8df-4000-92e0-fae3a7c6da64_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_ad1a8981-7968-48ee-8779-d1d2ceae872d" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_c59293c8-d8df-4000-92e0-fae3a7c6da64" xlink:to="loc_srt_RangeMember_ad1a8981-7968-48ee-8779-d1d2ceae872d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_39be676c-5734-4d30-97ec-000c0d8d0baa" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_ad1a8981-7968-48ee-8779-d1d2ceae872d" xlink:to="loc_srt_MinimumMember_39be676c-5734-4d30-97ec-000c0d8d0baa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_391bc7f5-0009-4640-9f6d-4bbf15ab2cfa" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_ad1a8981-7968-48ee-8779-d1d2ceae872d" xlink:to="loc_srt_MaximumMember_391bc7f5-0009-4640-9f6d-4bbf15ab2cfa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportableSegments_8b1749e6-60f9-4ba0-bceb-0792e437fa12" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NumberOfReportableSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_NumberOfReportableSegments_8b1749e6-60f9-4ba0-bceb-0792e437fa12" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SegmentAllocationGoodwillPercentage_04934944-9450-437b-b299-a2723e2ae974" xlink:href="newt-20241231.xsd#newt_SegmentAllocationGoodwillPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_newt_SegmentAllocationGoodwillPercentage_04934944-9450-437b-b299-a2723e2ae974" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SegmentAllocationEquityCapitalPercentage_bc73560b-8488-43f2-9b7a-efe851adc5ae" xlink:href="newt-20241231.xsd#newt_SegmentAllocationEquityCapitalPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_newt_SegmentAllocationEquityCapitalPercentage_bc73560b-8488-43f2-9b7a-efe851adc5ae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOperating_85c11085-6563-4a1f-a0a9-c55a0faf7da8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_InterestIncomeOperating_85c11085-6563-4a1f-a0a9-c55a0faf7da8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseOperating_f67a9eac-e209-4c8e-8685-db5c10a9cec9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_InterestExpenseOperating_f67a9eac-e209-4c8e-8685-db5c10a9cec9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNet_770d576e-6e55-4b57-8ab7-a4c82b27a348" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_InterestIncomeExpenseNet_770d576e-6e55-4b57-8ab7-a4c82b27a348" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForLoanLeaseAndOtherLosses_bc4564a5-24d5-40bd-9c9e-3d748c337a52" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProvisionForLoanLeaseAndOtherLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_ProvisionForLoanLeaseAndOtherLosses_bc4564a5-24d5-40bd-9c9e-3d748c337a52" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_ed202306-a594-4400-be66-d169509b8da4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_ed202306-a594-4400-be66-d169509b8da4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncome_66c5ca59-8937-4e66-af38-2d6d221dcf12" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_NoninterestIncome_66c5ca59-8937-4e66-af38-2d6d221dcf12" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InformationTechnologyAndDataProcessing_60d7a898-24cb-48d3-aee4-bf2eeebc9245" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InformationTechnologyAndDataProcessing"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_InformationTechnologyAndDataProcessing_60d7a898-24cb-48d3-aee4-bf2eeebc9245" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ElectronicPaymentProcessingExpense_106eecc5-3e0c-4d74-b9dc-37d98dfe1534" xlink:href="newt-20241231.xsd#newt_ElectronicPaymentProcessingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_newt_ElectronicPaymentProcessingExpense_106eecc5-3e0c-4d74-b9dc-37d98dfe1534" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense_617aab3a-f1ab-4ab8-9cca-bbc82f8de06d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_LaborAndRelatedExpense_617aab3a-f1ab-4ab8-9cca-bbc82f8de06d" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfessionalFees_54dedef2-6341-4b24-b273-2deea8df51e3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProfessionalFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_ProfessionalFees_54dedef2-6341-4b24-b273-2deea8df51e3" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_LoanProcessingFeeOther_d992846f-3b00-4878-abbc-821c8efdcc4b" xlink:href="newt-20241231.xsd#newt_LoanProcessingFeeOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_newt_LoanProcessingFeeOther_d992846f-3b00-4878-abbc-821c8efdcc4b" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_76781fa1-530f-43ee-a8e9-f1105185f4c9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_76781fa1-530f-43ee-a8e9-f1105185f4c9" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_e52e4a36-dac8-4635-a8a5-a68c4ec98f06" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_e52e4a36-dac8-4635-a8a5-a68c4ec98f06" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherGeneralAndAdministrativeExpense_00098c98-f291-4561-b459-0c90adf3d3b2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherGeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_OtherGeneralAndAdministrativeExpense_00098c98-f291-4561-b459-0c90adf3d3b2" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossAttributableToParent_254ae5a8-f558-4ffd-bd6b-383e4555f7d2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_IncomeLossAttributableToParent_254ae5a8-f558-4ffd-bd6b-383e4555f7d2" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_77ccaf80-979c-45a3-bd77-9dad5e3619d3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_77ccaf80-979c-45a3-bd77-9dad5e3619d3" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_0f967cdc-f966-400f-9879-321efb6d2115" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_NetIncomeLoss_0f967cdc-f966-400f-9879-321efb6d2115" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_95c0b438-8e18-4a7c-88de-f7f674b8fddf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_Assets_95c0b438-8e18-4a7c-88de-f7f674b8fddf" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill_cf857770-3e53-497e-8e8f-aeb1af80bbb6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IntangibleAssetsNetIncludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill_cf857770-3e53-497e-8e8f-aeb1af80bbb6" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_f90dc212-d421-42c2-9df6-f5b8f9b2010a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_a3a5dff8-fd9a-4472-ab61-0f80ce6da9a2" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_f90dc212-d421-42c2-9df6-f5b8f9b2010a" xlink:type="arc" order="22"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/NEWTEKONEINCPARENTCOMPANYONLYBalanceSheetDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#NEWTEKONEINCPARENTCOMPANYONLYBalanceSheetDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/NEWTEKONEINCPARENTCOMPANYONLYBalanceSheetDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems_89d35183-5125-40a6-80f7-2c141f3d770f" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CondensedBalanceSheetStatementsCaptionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedBalanceSheetStatementTable_df9ba052-be22-440a-ad38-cf2d0652a8ae" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CondensedBalanceSheetStatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems_89d35183-5125-40a6-80f7-2c141f3d770f" xlink:to="loc_srt_CondensedBalanceSheetStatementTable_df9ba052-be22-440a-ad38-cf2d0652a8ae" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_0166db51-87cc-4580-8a48-6bdfb5d99ec2" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_CondensedBalanceSheetStatementTable_df9ba052-be22-440a-ad38-cf2d0652a8ae" xlink:to="loc_srt_ConsolidatedEntitiesAxis_0166db51-87cc-4580-8a48-6bdfb5d99ec2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_0166db51-87cc-4580-8a48-6bdfb5d99ec2_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_0166db51-87cc-4580-8a48-6bdfb5d99ec2" xlink:to="loc_srt_ConsolidatedEntitiesDomain_0166db51-87cc-4580-8a48-6bdfb5d99ec2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_ee20a808-5099-492b-aa7f-5aef291d3c2e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_0166db51-87cc-4580-8a48-6bdfb5d99ec2" xlink:to="loc_srt_ConsolidatedEntitiesDomain_ee20a808-5099-492b-aa7f-5aef291d3c2e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ParentCompanyMember_ceda7192-27e1-47d9-9ad4-919d47cd0740" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ParentCompanyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_ee20a808-5099-492b-aa7f-5aef291d3c2e" xlink:to="loc_srt_ParentCompanyMember_ceda7192-27e1-47d9-9ad4-919d47cd0740" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsAbstract_0083dbfc-4353-4171-a15c-dc50a075511e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems_89d35183-5125-40a6-80f7-2c141f3d770f" xlink:to="loc_us-gaap_AssetsAbstract_0083dbfc-4353-4171-a15c-dc50a075511e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_04807922-a113-4de7-a7ce-3ce225e162b0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_0083dbfc-4353-4171-a15c-dc50a075511e" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_04807922-a113-4de7-a7ce-3ce225e162b0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableNet_e0d9fbe5-ba05-4892-83f7-433dd38f489e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NotesReceivableNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_0083dbfc-4353-4171-a15c-dc50a075511e" xlink:to="loc_us-gaap_NotesReceivableNet_e0d9fbe5-ba05-4892-83f7-433dd38f489e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_1b8f5bcb-f9c4-4b33-a533-07cfc42848ce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_0083dbfc-4353-4171-a15c-dc50a075511e" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_1b8f5bcb-f9c4-4b33-a533-07cfc42848ce" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_d329d98d-d828-48fa-8a27-3035e6bd2cce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_0083dbfc-4353-4171-a15c-dc50a075511e" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_d329d98d-d828-48fa-8a27-3035e6bd2cce" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssets_6e639f94-64cd-4abe-8648-aea9f2758c5c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_0083dbfc-4353-4171-a15c-dc50a075511e" xlink:to="loc_us-gaap_OtherAssets_6e639f94-64cd-4abe-8648-aea9f2758c5c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_ca04966c-1e5a-4aa9-a41e-b1aa6141fd72" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_0083dbfc-4353-4171-a15c-dc50a075511e" xlink:to="loc_us-gaap_Assets_ca04966c-1e5a-4aa9-a41e-b1aa6141fd72" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems_89d35183-5125-40a6-80f7-2c141f3d770f" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_ddac0003-c569-4a79-a852-1232bc6d1bc0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_LongTermDebtCurrent_ddac0003-c569-4a79-a852-1232bc6d1bc0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_fda954f2-e97f-4875-a099-ecd1ddbb25f2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_fda954f2-e97f-4875-a099-ecd1ddbb25f2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilities_065186b9-e5eb-45c6-bfde-fbf23eda277e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_OtherLiabilities_065186b9-e5eb-45c6-bfde-fbf23eda277e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DueToParticipants_1965bbe5-2efe-4275-abb5-efa98a946d74" xlink:href="newt-20241231.xsd#newt_DueToParticipants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_newt_DueToParticipants_1965bbe5-2efe-4275-abb5-efa98a946d74" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_3271418e-199e-44e2-b59c-a6ea3ee889a5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_Liabilities_3271418e-199e-44e2-b59c-a6ea3ee889a5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockValue_c594c8d9-c98b-40ea-b354-08bd2e09e07a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_PreferredStockValue_c594c8d9-c98b-40ea-b354-08bd2e09e07a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_b8bfee27-3380-4334-8c36-da4c66c987d2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_CommonStockValue_b8bfee27-3380-4334-8c36-da4c66c987d2" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_6dfa0701-8abc-4ba9-8121-f42c6a71a8dd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AdditionalPaidInCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_AdditionalPaidInCapital_6dfa0701-8abc-4ba9-8121-f42c6a71a8dd" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_0b94fda7-603f-4f14-986e-b1e590ceb0e9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_0b94fda7-603f-4f14-986e-b1e590ceb0e9" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_8a6031ef-cc8b-40c8-8870-3d4fe3cbcd11" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_8a6031ef-cc8b-40c8-8870-3d4fe3cbcd11" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_813104a3-5344-4832-b9e4-edc89efc4403" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_StockholdersEquity_813104a3-5344-4832-b9e4-edc89efc4403" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_0b95812a-cb6b-49d5-b24a-0d96f0fa5fec" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_7bf85d03-5c89-4e67-8205-7da94704de47" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_0b95812a-cb6b-49d5-b24a-0d96f0fa5fec" xlink:type="arc" order="12"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/NEWTEKONEINCPARENTCOMPANYONLYIncomeStatementDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#NEWTEKONEINCPARENTCOMPANYONLYIncomeStatementDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/NEWTEKONEINCPARENTCOMPANYONLYIncomeStatementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CondensedIncomeStatementsCaptionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedIncomeStatementTable_1c582282-35fb-4fc9-8d65-2d590d6ea501" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CondensedIncomeStatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_srt_CondensedIncomeStatementTable_1c582282-35fb-4fc9-8d65-2d590d6ea501" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_19a7825c-9a1d-4449-b823-be8944b08666" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_CondensedIncomeStatementTable_1c582282-35fb-4fc9-8d65-2d590d6ea501" xlink:to="loc_srt_ConsolidatedEntitiesAxis_19a7825c-9a1d-4449-b823-be8944b08666" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_19a7825c-9a1d-4449-b823-be8944b08666_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_19a7825c-9a1d-4449-b823-be8944b08666" xlink:to="loc_srt_ConsolidatedEntitiesDomain_19a7825c-9a1d-4449-b823-be8944b08666_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_517fe0ab-e760-4e6f-9b82-58aeb8a9caf6" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_19a7825c-9a1d-4449-b823-be8944b08666" xlink:to="loc_srt_ConsolidatedEntitiesDomain_517fe0ab-e760-4e6f-9b82-58aeb8a9caf6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ParentCompanyMember_2ee78ac5-ebd6-4e57-8e23-7aa7b542ea03" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ParentCompanyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_517fe0ab-e760-4e6f-9b82-58aeb8a9caf6" xlink:to="loc_srt_ParentCompanyMember_2ee78ac5-ebd6-4e57-8e23-7aa7b542ea03" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOperating_32c6cff4-a68b-4ad7-a75f-f00c52e70a8f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_us-gaap_InterestIncomeOperating_32c6cff4-a68b-4ad7-a75f-f00c52e70a8f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpense_f056e7da-c6ec-4465-8d93-773024a16520" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_us-gaap_InterestExpense_f056e7da-c6ec-4465-8d93-773024a16520" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNet_a38755ae-99f8-4bf9-aa00-b87541c13ed8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_us-gaap_InterestIncomeExpenseNet_a38755ae-99f8-4bf9-aa00-b87541c13ed8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncomeAbstract_1687677c-994d-4123-88c1-280405e52147" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestIncomeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_us-gaap_NoninterestIncomeAbstract_1687677c-994d-4123-88c1-280405e52147" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeDividend_b2078760-ce04-4c2c-b0e1-a75782e65410" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIncomeDividend"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_1687677c-994d-4123-88c1-280405e52147" xlink:to="loc_us-gaap_InvestmentIncomeDividend_b2078760-ce04-4c2c-b0e1-a75782e65410" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncomeOther_ae07b233-04a3-4ce5-8a01-82e63558bd27" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestIncomeOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_1687677c-994d-4123-88c1-280405e52147" xlink:to="loc_us-gaap_NoninterestIncomeOther_ae07b233-04a3-4ce5-8a01-82e63558bd27" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncome_3df8d02d-95ca-4566-a9ff-099610deee4d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestIncomeAbstract_1687677c-994d-4123-88c1-280405e52147" xlink:to="loc_us-gaap_NoninterestIncome_3df8d02d-95ca-4566-a9ff-099610deee4d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestExpenseAbstract_c17f8958-a18d-4e0e-a095-899f859ea162" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestExpenseAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_us-gaap_NoninterestExpenseAbstract_c17f8958-a18d-4e0e-a095-899f859ea162" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense_b285b72b-39a4-4ba8-bca2-8a2e7e792657" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_c17f8958-a18d-4e0e-a095-899f859ea162" xlink:to="loc_us-gaap_LaborAndRelatedExpense_b285b72b-39a4-4ba8-bca2-8a2e7e792657" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherGeneralAndAdministrativeExpense_ed781761-79e1-49c7-8e45-205a3970bafe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherGeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_c17f8958-a18d-4e0e-a095-899f859ea162" xlink:to="loc_us-gaap_OtherGeneralAndAdministrativeExpense_ed781761-79e1-49c7-8e45-205a3970bafe" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestExpense_e7b35abe-7aa7-4dcd-a137-d2c25ff9af13" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NoninterestExpenseAbstract_c17f8958-a18d-4e0e-a095-899f859ea162" xlink:to="loc_us-gaap_NoninterestExpense_e7b35abe-7aa7-4dcd-a137-d2c25ff9af13" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossAttributableToParent_91bf5838-70cc-4730-89cf-ba2ac8b1fb7f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_us-gaap_IncomeLossAttributableToParent_91bf5838-70cc-4730-89cf-ba2ac8b1fb7f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_5aeb053c-538d-41d9-9374-8ab4cc2b29b4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_5aeb053c-538d-41d9-9374-8ab4cc2b29b4" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_51afe741-75f0-4842-b67c-48269a6193bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_us-gaap_NetIncomeLoss_51afe741-75f0-4842-b67c-48269a6193bc" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromSubsidiariesNetOfTax_12340d58-1085-40eb-b31b-c48e62a19b7c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossFromSubsidiariesNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_us-gaap_IncomeLossFromSubsidiariesNetOfTax_12340d58-1085-40eb-b31b-c48e62a19b7c" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_5907aff5-8c12-463e-97d1-cd4c1dc19531" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_4c8f13fc-cbb6-4050-8af6-eb6609be5628" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_5907aff5-8c12-463e-97d1-cd4c1dc19531" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/NEWTEKONEINCPARENTCOMPANYONLYCashFlowStatementDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#NEWTEKONEINCPARENTCOMPANYONLYCashFlowStatementDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/NEWTEKONEINCPARENTCOMPANYONLYCashFlowStatementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_11b2e873-8563-4ecd-8bd4-c76a02206513" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CondensedCashFlowStatementsCaptionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedCashFlowStatementTable_ed185c80-2664-426a-a4b7-26bd2e016859" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CondensedCashFlowStatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_11b2e873-8563-4ecd-8bd4-c76a02206513" xlink:to="loc_srt_CondensedCashFlowStatementTable_ed185c80-2664-426a-a4b7-26bd2e016859" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_de0d0387-459e-422f-b54d-72084b6f2fac" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_CondensedCashFlowStatementTable_ed185c80-2664-426a-a4b7-26bd2e016859" xlink:to="loc_srt_ConsolidatedEntitiesAxis_de0d0387-459e-422f-b54d-72084b6f2fac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_de0d0387-459e-422f-b54d-72084b6f2fac_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_de0d0387-459e-422f-b54d-72084b6f2fac" xlink:to="loc_srt_ConsolidatedEntitiesDomain_de0d0387-459e-422f-b54d-72084b6f2fac_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_f669e3c8-bae2-4213-9d25-6c4334d81d7d" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_de0d0387-459e-422f-b54d-72084b6f2fac" xlink:to="loc_srt_ConsolidatedEntitiesDomain_f669e3c8-bae2-4213-9d25-6c4334d81d7d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ParentCompanyMember_1c39b586-e064-4cdc-aac0-8653968915d6" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ParentCompanyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_f669e3c8-bae2-4213-9d25-6c4334d81d7d" xlink:to="loc_srt_ParentCompanyMember_1c39b586-e064-4cdc-aac0-8653968915d6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_d7550dfe-8dff-49e3-a6bf-343c99643156" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_11b2e873-8563-4ecd-8bd4-c76a02206513" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_d7550dfe-8dff-49e3-a6bf-343c99643156" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_44960cc9-6718-4989-aa39-f7e422316eb2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_d7550dfe-8dff-49e3-a6bf-343c99643156" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_44960cc9-6718-4989-aa39-f7e422316eb2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_def55f6c-9b3c-4824-b727-d2bef3ef3442" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_d7550dfe-8dff-49e3-a6bf-343c99643156" xlink:to="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_def55f6c-9b3c-4824-b727-d2bef3ef3442" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnDispositionOfAssets1_facc2b5c-b0f1-48e3-9e30-5f95ff659f3a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainLossOnDispositionOfAssets1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_d7550dfe-8dff-49e3-a6bf-343c99643156" xlink:to="loc_us-gaap_GainLossOnDispositionOfAssets1_facc2b5c-b0f1-48e3-9e30-5f95ff659f3a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromSubsidiariesNetOfTax_af08f81f-7bfa-43ac-84bb-60c62f93eef3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossFromSubsidiariesNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_d7550dfe-8dff-49e3-a6bf-343c99643156" xlink:to="loc_us-gaap_IncomeLossFromSubsidiariesNetOfTax_af08f81f-7bfa-43ac-84bb-60c62f93eef3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_50d29008-6c91-4b7d-9794-909a7c157e79" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInOtherOperatingLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_d7550dfe-8dff-49e3-a6bf-343c99643156" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_50d29008-6c91-4b7d-9794-909a7c157e79" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_e43eafb1-c195-4574-96db-7e92ee0e9938" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInOtherOperatingAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_d7550dfe-8dff-49e3-a6bf-343c99643156" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_e43eafb1-c195-4574-96db-7e92ee0e9938" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet_7584ecd2-6166-4428-b8cf-812159c9d3a8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_d7550dfe-8dff-49e3-a6bf-343c99643156" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet_7584ecd2-6166-4428-b8cf-812159c9d3a8" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_17721fe2-2190-42c4-aadf-0f7160c76c1e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_d7550dfe-8dff-49e3-a6bf-343c99643156" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_17721fe2-2190-42c4-aadf-0f7160c76c1e" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_9ca844d6-d093-4f5d-854b-ffa0b4fb1b81" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_11b2e873-8563-4ecd-8bd4-c76a02206513" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_9ca844d6-d093-4f5d-854b-ffa0b4fb1b81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_8d191c6d-9ef6-4789-b2b7-aa0a0a2a618d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_9ca844d6-d093-4f5d-854b-ffa0b4fb1b81" xlink:to="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_8d191c6d-9ef6-4789-b2b7-aa0a0a2a618d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_aa992c24-685e-4948-93f3-460f32331364" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_9ca844d6-d093-4f5d-854b-ffa0b4fb1b81" xlink:to="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_aa992c24-685e-4948-93f3-460f32331364" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireInterestInSubsidiariesAndAffiliates_05499173-c5d2-4a65-b544-a0eeccf3a212" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireInterestInSubsidiariesAndAffiliates"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_9ca844d6-d093-4f5d-854b-ffa0b4fb1b81" xlink:to="loc_us-gaap_PaymentsToAcquireInterestInSubsidiariesAndAffiliates_05499173-c5d2-4a65-b544-a0eeccf3a212" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_ProceedsFromLoansHeldForInvestmentAtCost_4f120c95-82c0-4442-a77d-2da36a8d28ed" xlink:href="newt-20241231.xsd#newt_ProceedsFromLoansHeldForInvestmentAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_9ca844d6-d093-4f5d-854b-ffa0b4fb1b81" xlink:to="loc_newt_ProceedsFromLoansHeldForInvestmentAtCost_4f120c95-82c0-4442-a77d-2da36a8d28ed" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_5035b6fa-4ac8-474a-a233-50c31d4e0edf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireBusinessesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_9ca844d6-d093-4f5d-854b-ffa0b4fb1b81" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_5035b6fa-4ac8-474a-a233-50c31d4e0edf" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_80d6d98b-f7e9-4ad7-ae90-9c2a79bf388c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForProceedsFromOtherInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_9ca844d6-d093-4f5d-854b-ffa0b4fb1b81" xlink:to="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_80d6d98b-f7e9-4ad7-ae90-9c2a79bf388c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_fe9a98dc-1989-48ac-a57f-65034e9a9db0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_9ca844d6-d093-4f5d-854b-ffa0b4fb1b81" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_fe9a98dc-1989-48ac-a57f-65034e9a9db0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_6659685f-aee1-4282-b35c-d9c59796c8f1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_11b2e873-8563-4ecd-8bd4-c76a02206513" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_6659685f-aee1-4282-b35c-d9c59796c8f1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt_97a4ecb4-2bfe-4a40-afee-cb5ce42e9d02" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromIssuanceOfLongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_6659685f-aee1-4282-b35c-d9c59796c8f1" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt_97a4ecb4-2bfe-4a40-afee-cb5ce42e9d02" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfLongTermDebt_014fe38a-b372-43e6-9f49-138e2f1b6db1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RepaymentsOfLongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_6659685f-aee1-4282-b35c-d9c59796c8f1" xlink:to="loc_us-gaap_RepaymentsOfLongTermDebt_014fe38a-b372-43e6-9f49-138e2f1b6db1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_56211db2-a68f-4a20-a2be-b5bf18089818" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_6659685f-aee1-4282-b35c-d9c59796c8f1" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_56211db2-a68f-4a20-a2be-b5bf18089818" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfPreferredStockAndPreferenceStock_7b40d6bb-4d1c-482c-ab02-e25d6a12f240" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromIssuanceOfPreferredStockAndPreferenceStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_6659685f-aee1-4282-b35c-d9c59796c8f1" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfPreferredStockAndPreferenceStock_7b40d6bb-4d1c-482c-ab02-e25d6a12f240" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_f8be0ba5-8ee4-40dc-a69a-2620adad5fc7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_6659685f-aee1-4282-b35c-d9c59796c8f1" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_f8be0ba5-8ee4-40dc-a69a-2620adad5fc7" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividends_3c4e04a0-c565-49aa-bb59-a6b79fcb4bd2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsOfDividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_6659685f-aee1-4282-b35c-d9c59796c8f1" xlink:to="loc_us-gaap_PaymentsOfDividends_3c4e04a0-c565-49aa-bb59-a6b79fcb4bd2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_4a035f28-fbb1-4397-9483-d14dc9305398" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromPaymentsForOtherFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_6659685f-aee1-4282-b35c-d9c59796c8f1" xlink:to="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_4a035f28-fbb1-4397-9483-d14dc9305398" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_34c67689-eb05-4ac8-ad79-7614a3a0ce45" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_6659685f-aee1-4282-b35c-d9c59796c8f1" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_34c67689-eb05-4ac8-ad79-7614a3a0ce45" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_b3d7e390-614d-4292-965c-4b19883d5caf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_11b2e873-8563-4ecd-8bd4-c76a02206513" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_b3d7e390-614d-4292-965c-4b19883d5caf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_9717997a-653c-4ee8-ba98-5ed4c56ce667" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_11b2e873-8563-4ecd-8bd4-c76a02206513" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_9717997a-653c-4ee8-ba98-5ed4c56ce667" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_3b9df784-438f-4a3f-ae3e-76984312f7d4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/NEWTEKONEINCPARENTCOMPANYONLYNarrativeDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#NEWTEKONEINCPARENTCOMPANYONLYNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/NEWTEKONEINCPARENTCOMPANYONLYNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsLineItems_df74b9b1-3e7b-4c56-be43-df3da00e73ef" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCommitmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsTable_4dd01383-e12d-4769-b0af-83d7a8162aa1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCommitmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_df74b9b1-3e7b-4c56-be43-df3da00e73ef" xlink:to="loc_us-gaap_OtherCommitmentsTable_4dd01383-e12d-4769-b0af-83d7a8162aa1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_7275e099-a49c-410a-a200-6cf3b722f0bd" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OtherCommitmentsTable_4dd01383-e12d-4769-b0af-83d7a8162aa1" xlink:to="loc_dei_LegalEntityAxis_7275e099-a49c-410a-a200-6cf3b722f0bd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_7275e099-a49c-410a-a200-6cf3b722f0bd_default" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_7275e099-a49c-410a-a200-6cf3b722f0bd" xlink:to="loc_dei_EntityDomain_7275e099-a49c-410a-a200-6cf3b722f0bd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_9a00ad1f-35ab-4cb7-b450-8deeb1022f76" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_7275e099-a49c-410a-a200-6cf3b722f0bd" xlink:to="loc_dei_EntityDomain_9a00ad1f-35ab-4cb7-b450-8deeb1022f76" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NewtekBusinessLendingLLCMember_d1e07277-4bff-4d35-96f5-b00f723d0257" xlink:href="newt-20241231.xsd#newt_NewtekBusinessLendingLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_9a00ad1f-35ab-4cb7-b450-8deeb1022f76" xlink:to="loc_newt_NewtekBusinessLendingLLCMember_d1e07277-4bff-4d35-96f5-b00f723d0257" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NewtekMerchantSolutionsLLCMember_8155dfdd-f70c-4f0a-a962-b834c7c4b038" xlink:href="newt-20241231.xsd#newt_NewtekMerchantSolutionsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_9a00ad1f-35ab-4cb7-b450-8deeb1022f76" xlink:to="loc_newt_NewtekMerchantSolutionsLLCMember_8155dfdd-f70c-4f0a-a962-b834c7c4b038" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_8537eb86-325f-41d6-8273-eacb10bf4f72" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OtherCommitmentsTable_4dd01383-e12d-4769-b0af-83d7a8162aa1" xlink:to="loc_us-gaap_DebtInstrumentAxis_8537eb86-325f-41d6-8273-eacb10bf4f72" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_8537eb86-325f-41d6-8273-eacb10bf4f72_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_8537eb86-325f-41d6-8273-eacb10bf4f72" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_8537eb86-325f-41d6-8273-eacb10bf4f72_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_02e63e80-2d4d-4f07-b759-6d937d17f156" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_8537eb86-325f-41d6-8273-eacb10bf4f72" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_02e63e80-2d4d-4f07-b759-6d937d17f156" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SPVCapitalOneFacilityMember_b3b54d39-88fd-4d47-ab9c-3df107866866" xlink:href="newt-20241231.xsd#newt_SPVCapitalOneFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_02e63e80-2d4d-4f07-b759-6d937d17f156" xlink:to="loc_newt_SPVCapitalOneFacilityMember_b3b54d39-88fd-4d47-ab9c-3df107866866" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SPVDeutscheBankFacilityMember_f9feae58-be6c-4e21-baf2-ea024587ce6e" xlink:href="newt-20241231.xsd#newt_SPVDeutscheBankFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_02e63e80-2d4d-4f07-b759-6d937d17f156" xlink:to="loc_newt_SPVDeutscheBankFacilityMember_f9feae58-be6c-4e21-baf2-ea024587ce6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SPVOneFloridaBankFacilityMember_3ee6a250-5c4d-4503-aec7-e7dc5dc4cf1c" xlink:href="newt-20241231.xsd#newt_SPVOneFloridaBankFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_02e63e80-2d4d-4f07-b759-6d937d17f156" xlink:to="loc_newt_SPVOneFloridaBankFacilityMember_3ee6a250-5c4d-4503-aec7-e7dc5dc4cf1c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_WebsterFacilityMember_e859f839-1c68-4ed9-abcd-9621b2b061e8" xlink:href="newt-20241231.xsd#newt_WebsterFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_02e63e80-2d4d-4f07-b759-6d937d17f156" xlink:to="loc_newt_WebsterFacilityMember_e859f839-1c68-4ed9-abcd-9621b2b061e8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_431aee6b-3bdc-4a38-9a9e-68a568ddf6d0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OtherCommitmentsTable_4dd01383-e12d-4769-b0af-83d7a8162aa1" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_431aee6b-3bdc-4a38-9a9e-68a568ddf6d0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_431aee6b-3bdc-4a38-9a9e-68a568ddf6d0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_431aee6b-3bdc-4a38-9a9e-68a568ddf6d0" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_431aee6b-3bdc-4a38-9a9e-68a568ddf6d0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_07f8081f-beb8-4187-bc25-a24b358e0479" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_431aee6b-3bdc-4a38-9a9e-68a568ddf6d0" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_07f8081f-beb8-4187-bc25-a24b358e0479" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_7614afe9-11ec-448a-8b91-30dd6a41b51e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_07f8081f-beb8-4187-bc25-a24b358e0479" xlink:to="loc_us-gaap_LineOfCreditMember_7614afe9-11ec-448a-8b91-30dd6a41b51e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsByNatureAxis_3c7b349f-6804-4a1a-9bf8-42c9e24378b6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteeObligationsByNatureAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OtherCommitmentsTable_4dd01383-e12d-4769-b0af-83d7a8162aa1" xlink:to="loc_us-gaap_GuaranteeObligationsByNatureAxis_3c7b349f-6804-4a1a-9bf8-42c9e24378b6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsNatureDomain_3c7b349f-6804-4a1a-9bf8-42c9e24378b6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteeObligationsNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_GuaranteeObligationsByNatureAxis_3c7b349f-6804-4a1a-9bf8-42c9e24378b6" xlink:to="loc_us-gaap_GuaranteeObligationsNatureDomain_3c7b349f-6804-4a1a-9bf8-42c9e24378b6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsNatureDomain_ca24ffe5-db2d-4cb2-997b-ebc68beab5f6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteeObligationsNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_GuaranteeObligationsByNatureAxis_3c7b349f-6804-4a1a-9bf8-42c9e24378b6" xlink:to="loc_us-gaap_GuaranteeObligationsNatureDomain_ca24ffe5-db2d-4cb2-997b-ebc68beab5f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentGuaranteeMember_a9f03a42-85bc-4c99-94a8-3ba2b7c2ceb0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentGuaranteeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsNatureDomain_ca24ffe5-db2d-4cb2-997b-ebc68beab5f6" xlink:to="loc_us-gaap_PaymentGuaranteeMember_a9f03a42-85bc-4c99-94a8-3ba2b7c2ceb0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_81a04f4b-b28f-47dd-b2a9-83350259785e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_df74b9b1-3e7b-4c56-be43-df3da00e73ef" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_81a04f4b-b28f-47dd-b2a9-83350259785e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsMaximumExposure_6044a4d1-7fc1-4e8e-b856-a8ccd29c4d36" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteeObligationsMaximumExposure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_df74b9b1-3e7b-4c56-be43-df3da00e73ef" xlink:to="loc_us-gaap_GuaranteeObligationsMaximumExposure_6044a4d1-7fc1-4e8e-b856-a8ccd29c4d36" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_SBAObligationsSecuredFund_9c4242f9-3eee-45ec-be4f-7595fb7c0242" xlink:href="newt-20241231.xsd#newt_SBAObligationsSecuredFund"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_df74b9b1-3e7b-4c56-be43-df3da00e73ef" xlink:to="loc_newt_SBAObligationsSecuredFund_9c4242f9-3eee-45ec-be4f-7595fb7c0242" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.newtekone.com/role/SUBSEQUENTEVENTSDetails" xlink:type="simple" xlink:href="newt-20241231.xsd#SUBSEQUENTEVENTSDetails"/>
  <link:definitionLink xlink:role="http://www.newtekone.com/role/SUBSEQUENTEVENTSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventLineItems_fb24fa96-713b-4f49-87b0-7d6810eddd5f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTable_6aa1da54-bf81-4447-860b-0934fd16dbb4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_fb24fa96-713b-4f49-87b0-7d6810eddd5f" xlink:to="loc_us-gaap_SubsequentEventTable_6aa1da54-bf81-4447-860b-0934fd16dbb4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_d7120436-3d2b-42c3-b1f8-c38baed3f071" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_6aa1da54-bf81-4447-860b-0934fd16dbb4" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_d7120436-3d2b-42c3-b1f8-c38baed3f071" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_d7120436-3d2b-42c3-b1f8-c38baed3f071_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_d7120436-3d2b-42c3-b1f8-c38baed3f071" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_d7120436-3d2b-42c3-b1f8-c38baed3f071_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_f3dd3bca-5107-4abe-938e-6a8d2e30783f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_d7120436-3d2b-42c3-b1f8-c38baed3f071" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_f3dd3bca-5107-4abe-938e-6a8d2e30783f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_41609461-6f5e-4007-ad72-4d5eeb24859d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_f3dd3bca-5107-4abe-938e-6a8d2e30783f" xlink:to="loc_us-gaap_SubsequentEventMember_41609461-6f5e-4007-ad72-4d5eeb24859d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_aba5d4bd-6c79-4661-a432-fff719c5a414" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_6aa1da54-bf81-4447-860b-0934fd16dbb4" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_aba5d4bd-6c79-4661-a432-fff719c5a414" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_aba5d4bd-6c79-4661-a432-fff719c5a414_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_aba5d4bd-6c79-4661-a432-fff719c5a414" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_aba5d4bd-6c79-4661-a432-fff719c5a414_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_2e2b70f5-df51-425f-aad4-c27b695a457f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_aba5d4bd-6c79-4661-a432-fff719c5a414" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_2e2b70f5-df51-425f-aad4-c27b695a457f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_NewtekTechnologySolutionsIncMember_3b12ba02-f213-4958-8fc5-39c84c11bd6e" xlink:href="newt-20241231.xsd#newt_NewtekTechnologySolutionsIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_2e2b70f5-df51-425f-aad4-c27b695a457f" xlink:to="loc_newt_NewtekTechnologySolutionsIncMember_3b12ba02-f213-4958-8fc5-39c84c11bd6e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_acf62b8e-7829-40ef-8d92-e7d6fb0ea11c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_6aa1da54-bf81-4447-860b-0934fd16dbb4" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_acf62b8e-7829-40ef-8d92-e7d6fb0ea11c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_acf62b8e-7829-40ef-8d92-e7d6fb0ea11c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_acf62b8e-7829-40ef-8d92-e7d6fb0ea11c" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_acf62b8e-7829-40ef-8d92-e7d6fb0ea11c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_bcbcef0d-dd1f-4b60-a69f-15a496021471" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_acf62b8e-7829-40ef-8d92-e7d6fb0ea11c" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_bcbcef0d-dd1f-4b60-a69f-15a496021471" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_328ed3b1-106f-4f9a-807f-8b3ef126610b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_bcbcef0d-dd1f-4b60-a69f-15a496021471" xlink:to="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_328ed3b1-106f-4f9a-807f-8b3ef126610b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_769b82e3-e50f-442d-96b0-8e77610cc647" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_fb24fa96-713b-4f49-87b0-7d6810eddd5f" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_769b82e3-e50f-442d-96b0-8e77610cc647" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DisposalGroupIncludingDiscontinuedOperationConsiderationSharesIssued_e587a745-30eb-4773-81f6-f39141aab304" xlink:href="newt-20241231.xsd#newt_DisposalGroupIncludingDiscontinuedOperationConsiderationSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_fb24fa96-713b-4f49-87b0-7d6810eddd5f" xlink:to="loc_newt_DisposalGroupIncludingDiscontinuedOperationConsiderationSharesIssued_e587a745-30eb-4773-81f6-f39141aab304" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_newt_DisposalGroupIncludingDiscontinuedOperationConsiderationEarnOutReceivable_6fe7b738-6d90-46e8-b559-eed4e786cb1b" xlink:href="newt-20241231.xsd#newt_DisposalGroupIncludingDiscontinuedOperationConsiderationEarnOutReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_fb24fa96-713b-4f49-87b0-7d6810eddd5f" xlink:to="loc_newt_DisposalGroupIncludingDiscontinuedOperationConsiderationEarnOutReceivable_6fe7b738-6d90-46e8-b559-eed4e786cb1b" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-roles-2024.xsd#eedm"/>
  <link:definitionLink xlink:role="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization" xlink:type="arc" order="691"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss" xlink:type="arc" order="692"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSalesOfLoansNet" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainLossOnSalesOfLoansNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="loc_us-gaap_GainLossOnSalesOfLoansNet" xlink:type="arc" order="693"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableAndOtherAccruedLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsPayableAndOtherAccruedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract" xlink:to="loc_us-gaap_AccountsPayableAndOtherAccruedLiabilities" xlink:type="arc" order="31"/>
  </link:definitionLink>
</link:linkbase>
