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

    <schemaVersion>X0609</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-06-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001809104</issuerCik>
        <issuerName>Alight, Inc. / Delaware</issuerName>
        <issuerTradingSymbol>ALIT</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001730708</rptOwnerCik>
            <rptOwnerName>Williams Lenore D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>C/O ALIGHT, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>510 LAKE COOK ROAD, SUITE 400</rptOwnerStreet2>
            <rptOwnerCity>DEERFIELD</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60015</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-06-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2455</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>11.20</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10849</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Quarterly award of shares elected in lieu of cash retainer of $27,500 for service as a member of the Board of Directors and granted pursuant to the Alight, Inc. 2021 Omnibus Incentive Plan.   The number of shares granted was calculated by dividing the cash retainer by $11.20, the closing price of the Issuer's ordinary shares on June 30, 2026, as adjusted to reflect the 1-for-20 reverse stock split of the Issuer's Class A common stock on such date, and rounding down to the next whole share.</footnote>
        <footnote id="F2">Includes restricted stock units scheduled to vest in the future.</footnote>
        <footnote id="F3">Securities listed in this filing have been adjusted to reflect a 1-for-20 reverse split of the Issuer's Class A common stock effective as of June 30, 2026.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ John A. Mikowski, Deputy General Counsel and Assistant Corporate Secretary, as Attorney-in-Fact</signatureName>
        <signatureDate>2026-07-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
