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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-09-24</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001453593</issuerCik>
        <issuerName>Xtant Medical Holdings, Inc.</issuerName>
        <issuerTradingSymbol>XTNT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001387652</rptOwnerCik>
            <rptOwnerName>McNamara Robert</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>664 CRUISER LANE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BELGRADE</rptOwnerCity>
            <rptOwnerState>MT</rptOwnerState>
            <rptOwnerZipCode>59714</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $0.000001 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2019-09-24</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>9027</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>29860</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares are subject to a restricted stock unit award granted under the Xtant Medical Holdings, Inc. 2018 Equity Incentive Plan and will vest and become issuable on February 15, 2020, conditioned upon the reporting person remaining a director of Xtant through the vesting date.</footnote>
        <footnote id="F2">Includes 9,027 shares to be issued upon vesting pursuant to restricted stock unit award granted under the Xtant Medical Holdings, Inc. 2018 Equity Incentive Plan, conditioned upon the reporting person remaining a director of Xtant through the vesting date, and 10,417 shares issued as part of a restricted stock award granted under the Amended and Restated Xtant Equity Incentive Plan, which shares are subject to forfeiture until vested.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Amy Culbert, attorney-in-fact</signatureName>
        <signatureDate>2019-09-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
