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

    <schemaVersion>X0206</schemaVersion>

    <documentType>3/A</documentType>

    <periodOfReport>2025-10-16</periodOfReport>

    <dateOfOriginalSubmission>2026-03-03</dateOfOriginalSubmission>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0002025416</issuerCik>
        <issuerName>OBOOK HOLDINGS INC.</issuerName>
        <issuerTradingSymbol>OWLS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0002112937</rptOwnerCik>
            <rptOwnerName>CHUNG TING AN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>9F., NO. 28, WENCHENG RD., BEITOU DIST.,</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TAIPEI CITY</rptOwnerCity>
            <rptOwnerState>F5</rptOwnerState>
            <rptOwnerZipCode>112</rptOwnerZipCode>
            <rptOwnerStateDescription>TAIWAN</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief of Staff</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12900</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2026-08-08</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>38700</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The restricted stock units represent the right to receive an aggregate of 38,700 Class A Common Shares, reflecting the unvested portion of the original grant, and vest in three equal annual installments of 12,900 shares on August 8, 2026, August 8, 2027 and August 8, 2028 pursuant to the Issuer's equity incentive plan. The restricted stock units do not have an expiration date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/Chung Ting An</signatureName>
        <signatureDate>2026-03-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
