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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-04-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001110507</issuerCik>
        <issuerName>ESCHELON TELECOM INC</issuerName>
        <issuerTradingSymbol>ESCH</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001294921</rptOwnerCik>
            <rptOwnerName>Smith Richard Allen Jr</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>730 SECOND AVENUE SOUTH</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 900</rptOwnerStreet2>
            <rptOwnerCity>MINNEAPOLIS</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55402</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CEO &amp; President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Common Stock Options</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.20</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-04-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>75000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.20</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2005-04-01</value>
            </exerciseDate>
            <expirationDate>
                <value>2015-04-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>75000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2708337</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">On February 6, 2003, Mr. Smith was granted options to purchase 1,649,686 shares of common stock.  1,009,786 shares are fully vested with the remaining 639,900 shares vesting in equal installments beginning on February 7, 2006. On February 7, 2003, Mr. Smith was granted options to purchase 633,653 shares of common stock.  633,653 shares are fully vested.  On May 22, 2003, Mr. Smith was granted options to purchase 200,000 shares of common stock, with 20% of the options vesting on the grant date and the remaining shares vesting 20% on each subsequent anniversary of the grant date. On May 20, 2004, Mr. Smith was granted options to purchase 150,000 shares of common stock, with 20% of the options vesting on the grant date and the remaining shares vesting 20% on each subsequent</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Richard Allen Smith Jr</signatureName>
        <signatureDate>2005-04-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
