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

    <documentType>4</documentType><periodOfReport>2003-08-01</periodOfReport>
    <issuer>
        <issuerCik>0001116521</issuerCik>
        <issuerName>AVAYA INC</issuerName>
        <issuerTradingSymbol>AV</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001221544</rptOwnerCik>
            <rptOwnerName>PETERSON DONALD</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>1</isDirector><isOfficer>1</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther><officerTitle>Chairman, CEO and President</officerTitle></reportingOwnerRelationship></reportingOwner><nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2001-11-01</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>J</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>185202</value></transactionShares><transactionPricePerShare><footnoteId id="F1"/></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>421382</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2002-08-01</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>J</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>86539</value></transactionShares><transactionPricePerShare><footnoteId id="F1"/></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>507921</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-08-01</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>J</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>86539</value></transactionShares><transactionPricePerShare><footnoteId id="F1"/></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>594460</value><footnoteId id="F2"/></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></nonDerivativeTransaction></nonDerivativeTable><derivativeTable><derivativeTransaction><securityTitle><value>Restricted Stock Units</value></securityTitle><conversionOrExercisePrice><footnoteId id="F1"/></conversionOrExercisePrice><transactionDate><value>2001-11-01</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>M</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>185202</value></transactionShares><transactionPricePerShare><footnoteId id="F1"/></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><footnoteId id="F1"/></exerciseDate><expirationDate><footnoteId id="F1"/></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>185202</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>5897072</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeTransaction><derivativeTransaction><securityTitle><value>Restricted Stock Units</value></securityTitle><conversionOrExercisePrice><footnoteId id="F1"/></conversionOrExercisePrice><transactionDate><value>2002-08-01</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>M</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>86539</value></transactionShares><transactionPricePerShare><footnoteId id="F1"/></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><footnoteId id="F1"/></exerciseDate><expirationDate><footnoteId id="F1"/></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>86539</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>5983611</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeTransaction><derivativeTransaction><securityTitle><value>Restricted Stock Units</value></securityTitle><conversionOrExercisePrice><footnoteId id="F1"/></conversionOrExercisePrice><transactionDate><value>2003-08-01</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>M</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>86539</value></transactionShares><transactionPricePerShare><footnoteId id="F1"/></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><footnoteId id="F1"/></exerciseDate><expirationDate><footnoteId id="F1"/></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>86539</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>6070150</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeTransaction></derivativeTable><footnotes><footnote id="F1">On 11/1/2001, 8/1/2002 and 8/1/2003, the reporting person had restricted stock units from prior grants vest in amounts of 185,202, 86,539 and 86,539 restricted stock units, respectively.  Pursuant to an election made by the reporting person, receipt of the underlying shares was deferred by the reporting person until termination of employment, or until such time as the issuer's Corporate Governance and Compensation Committee so determines.</footnote><footnote id="F2">Total includes 280,000 restricted stock units that have not yet vested.</footnote></footnotes><remarks/><ownerSignature><signatureName>Donald K. Peterson</signatureName><signatureDate>2003-08-02</signatureDate></ownerSignature></ownershipDocument>

