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

    <schemaVersion>X0609</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-03-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001947210</issuerCik>
        <issuerName>High Roller Technologies, Inc.</issuerName>
        <issuerTradingSymbol>ROLR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0002066846</rptOwnerCik>
            <rptOwnerName>Felman Adam Jonathan</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>400 SOUTH 4TH STREET,</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 500-#390</rptOwnerStreet2>
            <rptOwnerCity>LAS VEGAS</rptOwnerCity>
            <rptOwnerState>NV</rptOwnerState>
            <rptOwnerZipCode>89101</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-03-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>100000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>164550</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The reported transaction involved the Reporting Person's receipt of 100,000 restricted stock units (&quot;RSUs&quot;). The RSUs were granted pursuant to the High Roller Technologies, Inc. 2024 Equity Incentive Plan. Each RSU represents a contingent right to receive one share of common stock upon vesting. Of the total RSUs reported, 40,000 RSUs shall vest in equal quarterly installments over a period of three years, and the remaining 60,000 RSUs are subject to vesting upon the achievement of certain performance conditions, as determined and certified by the board of directors of the Issuer, subject to the Reporting Person's continued service.</footnote>
        <footnote id="F2">The total reported in Column 5 includes (i) the 100,000 newly awarded RSUs, (ii) 50,000 RSUs of which 12,500 have vested, and (iii) 14,550 shares of common stock.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Adam Felman</signatureName>
        <signatureDate>2026-03-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
