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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2006-06-28</periodOfReport>

    <dateOfOriginalSubmission>2006-06-30</dateOfOriginalSubmission>

    <issuer>
        <issuerCik>0000106926</issuerCik>
        <issuerName>WHITNEY HOLDING CORP</issuerName>
        <issuerTradingSymbol>WTNY</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001249751</rptOwnerCik>
            <rptOwnerName>CALLICUTT THOMAS L JR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>228 ST. CHARLES AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW ORLEANS</rptOwnerCity>
            <rptOwnerState>LA</rptOwnerState>
            <rptOwnerZipCode>70130</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CFO/ Executive Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Nonqual opt</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>35.41</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-06-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>35.41</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2009-06-28</value>
            </exerciseDate>
            <expirationDate>
                <value>2016-06-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Comm stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>10000</value>
                    <footnoteId id="F2"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The fair market value of the Company's common stock on the date of grant (6/28/06) was $35.16, which was originally reported as the exercise price for the options.  The issuer's Comensation Committee intended, however, that the exercise price for the options be the greater of the fair market value of the common stock on 6/28/06 (the date of grant of these options) or 6/27/06 (the date options were granted to non-officer employees).  The fair market value of the issuer's common stock on 6/27/06 was $35.41, and this amended Form 4 is being filed to correctly report the higher exercise price for the options.</footnote>
        <footnote id="F2">Granted under the Company's Long Term Incentive Plan in accordance with Rule 16b-3(d).</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Patricia K. Loupe, Asst. Corporate Secretary of Whitney Holding Corp. and attorney-in-fact</signatureName>
        <signatureDate>2006-07-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
