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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-10-24</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000884713</issuerCik>
        <issuerName>COTT CORP /CN/</issuerName>
        <issuerTradingSymbol>COT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001188508</rptOwnerCik>
            <rptOwnerName>SHEPPARD JOHN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>4928 LYFORD CAY ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TAMPA</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33629</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2005-10-24</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>15000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>14.1</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>37381.89</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Includes 32,000 Shares held directly; 4,544.392 vested Shares held in trust pursuant to the Executive Investment Share Purhcase Plan (the &quot;Plan&quot;) (which replaced the Executive Incentive Share Compensation Plan (&quot;EISCP&quot;)) that vested on or before 01/02/05; 216.85 vested Shares held pursuant to the Restated Cott USA 401(k) Savings and Retirement Plan (as at 09/31/05); and 620.648 vested Shares under the US Employee Share Purchase Plan (as at 09/31/05).  The reporting individual also holds 10,619.206 unvested Shares held in trust that were acquired pursuant to the Plan and the EISCP (which replaced the Plan) in 2004 and 2005; and 54.21 unvested Shares held pursuant to the Restated Cott USA 401(k) Savings and Retirement Plan (as at 09/31/05).</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Andrea Szanto, by power of attorney</signatureName>
        <signatureDate>2005-10-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
