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

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-04-02</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001249445</rptOwnerCik>
            <rptOwnerName>LIPPMAN ALFRED S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1025 VICTOR II BOULEVARD</rptOwnerStreet1>
            <rptOwnerStreet2>INGLEWOOD MALL</rptOwnerStreet2>
            <rptOwnerCity>MORGAN CITY</rptOwnerCity>
            <rptOwnerState>LA</rptOwnerState>
            <rptOwnerZipCode>70380</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common stock no par value</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>37007</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Common stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>31.985</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2003-06-30</value>
            </exerciseDate>
            <expirationDate>
                <value>2013-06-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3000</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom stock units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-04-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3.86</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>42.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>1988-08-08</value>
            </exerciseDate>
            <expirationDate>
                <value>1988-08-08</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3.86</value>
                    <footnoteId id="F3"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>494.83</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">As previously reported, Mr. Lippman also has outstanding options to acquire up to 12,000 shares of stock at exercise prices ranging from $20.333 to $33.9166 pursuant to the Company's Directors Compensation Plans.</footnote>
        <footnote id="F2">In addition, Mr. Lippman has 56,419 shares of Whitney stock in the Lippman, Mahfouz &amp; Martin 401(k) Savings &amp; Retirement Plan f/b/o Alfred S. LIppman</footnote>
        <footnote id="F3">Phantom stock units are accrued on a 1-for-1 basis under the Company's Directors' Compensation Plan and are to be settled 100% of WHC common stock upon the requesting person's pre-determined payment after retirement.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Patricia K. Loupe,  Asst. Corp. Secretary of Whitney Holding Corporation and attorney-in-fact</signatureName>
        <signatureDate>2004-04-02</signatureDate>
    </ownerSignature>
</ownershipDocument>

