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

    <schemaVersion>X0609</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2026-06-04</periodOfReport>

    <dateOfOriginalSubmission>2026-06-08</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000914156</issuerCik>
        <issuerName>UFP TECHNOLOGIES INC</issuerName>
        <issuerTradingSymbol>UFPT</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001641388</rptOwnerCik>
            <rptOwnerName>Hassett Joseph John</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>C/O UFP TECHNOLOGIES, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>100 HALE STREET</rptOwnerStreet2>
            <rptOwnerCity>NEWBURYPORT</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01950</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, $.01 Par Value</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2602</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">This amendment is being filed to correct the Amount of Shares Beneficially owned by the Reporting Person previously reported on the Form 4 filed on June 8, 2026. Due to an administrative error, the original filing incorrectly reported that 2,425 shares were beneficially owned following the transaction being reported. The correct number of shares beneficially owned, as reported in this amendment, was 2,602 shares.</footnote>
    </footnotes>

    <remarks>Exhibit 24: Power of Attorney</remarks>

    <ownerSignature>
        <signatureName>/s/ Rebekah Mihm, as Attorney-in-Fact</signatureName>
        <signatureDate>2026-08-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
