<?xml version="1.0"?><?xml-stylesheet type="text/xsl" href="../4_X02.xsl"?><ownershipDocument>    <schemaVersion>X0303</schemaVersion>    <documentType>4</documentType>    <periodOfReport>2010-04-05</periodOfReport>    <notSubjectToSection16>0</notSubjectToSection16>    <issuer>        <issuerCik>0001325281</issuerCik>        <issuerName>KAPSTONE PAPER &amp; PACKAGING CORP</issuerName>        <issuerTradingSymbol>KS</issuerTradingSymbol>    </issuer>    <reportingOwner>        <reportingOwnerId>            <rptOwnerCik>0001327234</rptOwnerCik>            <rptOwnerName>Rahman Muhit</rptOwnerName>        </reportingOwnerId>        <reportingOwnerAddress>            <rptOwnerStreet1>8550 WILLOW RUN COURT</rptOwnerStreet1>            <rptOwnerStreet2></rptOwnerStreet2>            <rptOwnerCity>CINCINNATI</rptOwnerCity>            <rptOwnerState>OH</rptOwnerState>            <rptOwnerZipCode>45243</rptOwnerZipCode>            <rptOwnerStateDescription></rptOwnerStateDescription>        </reportingOwnerAddress>        <reportingOwnerRelationship>            <isDirector>1</isDirector>            <isOfficer>0</isOfficer>            <isTenPercentOwner>0</isTenPercentOwner>            <isOther>0</isOther>        </reportingOwnerRelationship>    </reportingOwner>    <nonDerivativeTable>        <nonDerivativeTransaction>            <securityTitle>                <value>Common</value>            </securityTitle>            <transactionDate>                <value>2010-04-05</value>            </transactionDate>            <transactionCoding>                <transactionFormType>4</transactionFormType>                <transactionCode>S</transactionCode>                <equitySwapInvolved>0</equitySwapInvolved>            </transactionCoding>            <transactionTimeliness>                <value></value>            </transactionTimeliness>            <transactionAmounts>                <transactionShares>                    <value>46754</value>                    <footnoteId id="F1"/>                </transactionShares>                <transactionPricePerShare>                    <value>12.5128</value>                    <footnoteId id="F2"/>                </transactionPricePerShare>                <transactionAcquiredDisposedCode>                    <value>D</value>                </transactionAcquiredDisposedCode>            </transactionAmounts>            <postTransactionAmounts>                <sharesOwnedFollowingTransaction>                    <value>471346</value>                </sharesOwnedFollowingTransaction>            </postTransactionAmounts>            <ownershipNature>                <directOrIndirectOwnership>                    <value>D</value>                </directOrIndirectOwnership>            </ownershipNature>        </nonDerivativeTransaction>        <nonDerivativeTransaction>            <securityTitle>                <value>Common</value>            </securityTitle>            <transactionDate>                <value>2010-04-06</value>            </transactionDate>            <transactionCoding>                <transactionFormType>4</transactionFormType>                <transactionCode>S</transactionCode>                <equitySwapInvolved>0</equitySwapInvolved>            </transactionCoding>            <transactionTimeliness>                <value></value>            </transactionTimeliness>            <transactionAmounts>                <transactionShares>                    <value>50000</value>                    <footnoteId id="F1"/>                </transactionShares>                <transactionPricePerShare>                    <value>12.5474</value>                    <footnoteId id="F2"/>                </transactionPricePerShare>                <transactionAcquiredDisposedCode>                    <value>D</value>                </transactionAcquiredDisposedCode>            </transactionAmounts>            <postTransactionAmounts>                <sharesOwnedFollowingTransaction>                    <value>421346</value>                </sharesOwnedFollowingTransaction>            </postTransactionAmounts>            <ownershipNature>                <directOrIndirectOwnership>                    <value>D</value>                </directOrIndirectOwnership>            </ownershipNature>        </nonDerivativeTransaction>        <nonDerivativeTransaction>            <securityTitle>                <value>Common</value>            </securityTitle>            <transactionDate>                <value>2010-04-07</value>            </transactionDate>            <transactionCoding>                <transactionFormType>4</transactionFormType>                <transactionCode>S</transactionCode>                <equitySwapInvolved>0</equitySwapInvolved>            </transactionCoding>            <transactionTimeliness>                <value></value>            </transactionTimeliness>            <transactionAmounts>                <transactionShares>                    <value>3246</value>                    <footnoteId id="F1"/>                </transactionShares>                <transactionPricePerShare>                    <value>12.51</value>                    <footnoteId id="F2"/>                </transactionPricePerShare>                <transactionAcquiredDisposedCode>                    <value>D</value>                </transactionAcquiredDisposedCode>            </transactionAmounts>            <postTransactionAmounts>                <sharesOwnedFollowingTransaction>                    <value>418100</value>                </sharesOwnedFollowingTransaction>            </postTransactionAmounts>            <ownershipNature>                <directOrIndirectOwnership>                    <value>D</value>                </directOrIndirectOwnership>            </ownershipNature>        </nonDerivativeTransaction>    </nonDerivativeTable>    <footnotes>        <footnote id="F1">Shares disposed of pursuant to a Rule 10b5-1 Plan</footnote>        <footnote id="F2">The price is weighted average price. The reporting person will provide any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares purchased at each price within a range.</footnote>    </footnotes>    <ownerSignature>        <signatureName>Muhit Rahman by Power of Attorney</signatureName>        <signatureDate>2010-04-07</signatureDate>    </ownerSignature></ownershipDocument>
