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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2010-11-05</periodOfReport>

    <dateOfOriginalSubmission>2010-11-08</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001002135</issuerCik>
        <issuerName>WESTELL TECHNOLOGIES INC</issuerName>
        <issuerTradingSymbol>WSTL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001008281</rptOwnerCik>
            <rptOwnerName>SIMON MELVIN J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1></rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity></rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode></rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>26405</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.8249</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>87804</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Simon Trust</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Held in Melvin J. Simon Trust DTD 10-19-84 - Melvin J. Simon Trustee (the &quot;Simon Trust).</footnote>
    </footnotes>

    <remarks>This amendment is being filed to correct the code used to report the reporting person's disposition of shares on 11/5/2010; the transaction was incorrectly reported on the Form 4 as an acquisition.  In addition, column 5 of Table 1 has been updated to exclude the shares of the Class B Common Stock held by Robert C. Penny and Mr. Simon, as trustees pursuant to the Voting Trust Agreement, dated February 23, 1994, as amended, among Messrs. Penny and Simon, and certain members of the Penny and Simon family.  Mr. Simon disclaims beneficial ownership with respect to all shares held in the Voting Trust for which he does not have a pecuniary interest.</remarks>

    <ownerSignature>
        <signatureName>/s/ Amy T. Forster, by power of attorney</signatureName>
        <signatureDate>2011-01-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
