<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0609</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-08-11</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001785424</issuerCik>
        <issuerName>Katapult Holdings, Inc.</issuerName>
        <issuerTradingSymbol>KPLT</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001657995</rptOwnerCik>
            <rptOwnerName>Walsh Nancy A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>5360 LEGACY DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2>BUILDING 2</rptOwnerStreet2>
            <rptOwnerCity>PLANO</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75024-7141</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <remarks>The reporting person resigned as the issuer's Chief Financial Officer effective August 11, 2026. As a result, the reporting person is no longer subject to Section 16 in connection with her transactions in the equity securities of the issuer and therefore will no longer report any such transactions on Form 4 or Form 5.</remarks>

    <ownerSignature>
        <signatureName>/s/ Ryan Wigdor as attorney-in-fact for Nancy Walsh</signatureName>
        <signatureDate>2026-08-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
