<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType><periodOfReport>2003-11-07</periodOfReport>
    <issuer>
        <issuerCik>0001116521</issuerCik>
        <issuerName>AVAYA INC</issuerName>
        <issuerTradingSymbol>AV</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001240149</rptOwnerCik>
            <rptOwnerName>PAI AMARNATH K</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>211 MT. AIRY ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BASKING RIDGE</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07920</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector><isOfficer>1</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther><officerTitle>VP/Controller/Princ.Acct.Off.</officerTitle></reportingOwnerRelationship></reportingOwner><nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-11-07</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>A</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>12000</value></transactionShares><transactionPricePerShare><footnoteId id="F1"/></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>46672</value><footnoteId id="F2"/></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></nonDerivativeTransaction></nonDerivativeTable><derivativeTable><derivativeTransaction><securityTitle><value>Stock Options</value></securityTitle><conversionOrExercisePrice><value>13.30</value></conversionOrExercisePrice><transactionDate><value>2003-11-07</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>A</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>50000</value></transactionShares><transactionPricePerShare><value>13.30</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><footnoteId id="F3"/></exerciseDate><expirationDate><value>2010-11-06</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>50000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>140000</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeTransaction></derivativeTable><footnotes><footnote id="F1">Represents a grant of restricted stock units (RSUs) made to the reporting person on 11/7/2003.  These RSUs vest 50% on 11/7/2006 and 50% on 11/7/2007.  Shares of Avaya Common Stock underlying RSUs are issued for vested RSUs at no cost on a one-for-one basis.</footnote><footnote id="F2">Includes 46,672 restricted stock units that have not yet vested.</footnote><footnote id="F3">Represents a grant of 50,000 stock options made on 11/7/2003.  These stock options vest 1/3 on 11/7/2004 and 1/36 each month thereafter.</footnote></footnotes><remarks/><ownerSignature><signatureName>Amarnath K. Pai</signatureName><signatureDate>2003-11-10</signatureDate></ownerSignature></ownershipDocument>

