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

    <schemaVersion>X0206</schemaVersion>

    <documentType>3/A</documentType>

    <periodOfReport>2015-01-27</periodOfReport>

    <dateOfOriginalSubmission>2015-02-03</dateOfOriginalSubmission>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001362468</issuerCik>
        <issuerName>Allegiant Travel CO</issuerName>
        <issuerTradingSymbol>ALGT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001632467</rptOwnerCik>
            <rptOwnerName>Anderson Gregory Clark</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1201 NORTH TOWN CENTER DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LAS VEGAS</rptOwnerCity>
            <rptOwnerState>NV</rptOwnerState>
            <rptOwnerZipCode>89144</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Principal Accounting Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2074</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The sole reason for the filing of this Form 3/A is to correct the title of the beneficial owner, who serves as an officer of the issuer.

The number of shares shown as beneficially owned on this Form 3/A is identical to the number of shares shown as beneficially owned on the original Form 3.  The reason for re-reporting the securities owned by the beneficial owner in Table 1 on this Form 3/A is solely to allow for electronic filing of this Form 3/A, as the electronic filing system will not accept a filing that does not include an entry on Table 1 or Table 2.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Robert B. Goldberg, under power of attorney</signatureName>
        <signatureDate>2015-02-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
