<SUBMISSION>
<ACCESSION-NUMBER>0001050377-04-000002
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20031231
<FILING-DATE>20040105
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>BEFFA NEGRINI DAVID
<CIK>0001190007
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>000-23827
<FILM-NUMBER>04503527
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>PC CONNECTION
<STREET2>730 MILFORD ROAD
<CITY>MERRIMACK
<STATE>NH
<ZIP>03054
</MAIL-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>PC CONNECTION INC
<CIK>0001050377
<ASSIGNED-SIC>5961
<IRS-NUMBER>020513618
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>ROUTE 101A
<STREET2>730 MILFORD RD
<CITY>MERRIMACK
<STATE>NH
<ZIP>03054
<PHONE>6036832000
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>ROUTE 101A
<STREET2>730 MILFORD RD
<CITY>MERRIMACK
<STATE>NH
<ZIP>03054
</MAIL-ADDRESS>
</ISSUER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>

<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2003-12-31</periodOfReport>


    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001050377</issuerCik>
        <issuerName>PC CONNECTION INC</issuerName>
        <issuerTradingSymbol>PCCC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001190007</rptOwnerCik>
            <rptOwnerName>BEFFA NEGRINI DAVID</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>PC CONNECTION</rptOwnerStreet1>
            <rptOwnerStreet2>730 MILFORD ROAD</rptOwnerStreet2>
            <rptOwnerCity>MERRIMACK</rptOwnerCity>
            <rptOwnerState>NH</rptOwnerState>
            <rptOwnerZipCode>03054</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President, Corporate Comm</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>

        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2003-12-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1315</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>5.7035</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>77656</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>

    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares acquired through the PC Connection Employee Stock Purchase Plan</footnote>
    </footnotes>


    <ownerSignature>
        <signatureName>David Beffa-Negrini</signatureName>
        <signatureDate>2004-01-05</signatureDate>
    </ownerSignature>

</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
