-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0000811612-08-000038.txt : 20080606
<SEC-HEADER>0000811612-08-000038.hdr.sgml : 20080606
<ACCEPTANCE-DATETIME>20080606094225
ACCESSION NUMBER:		0000811612-08-000038
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080604
FILED AS OF DATE:		20080606
DATE AS OF CHANGE:		20080606

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COMMERCE GROUP INC /MA
		CENTRAL INDEX KEY:			0000811612
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		IRS NUMBER:				042599931
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		211 MAIN ST
		CITY:			WEBSTER
		STATE:			MA
		ZIP:			01570
		BUSINESS PHONE:		5089439000

	MAIL ADDRESS:	
		STREET 1:		211 MAIN STREET
		STREET 2:		211 MAIN STREET
		CITY:			WEBSTER
		STATE:			MA
		ZIP:			01570

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hawie John Weston
		CENTRAL INDEX KEY:			0001363853

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13672
		FILM NUMBER:		08884486

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		860 935 9318

	MAIL ADDRESS:	
		STREET 1:		374 THOMPSON ROAD
		CITY:			THOMPSON
		STATE:			CT
		ZIP:			06277
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-06-04</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0000811612</issuerCik>
        <issuerName>COMMERCE GROUP INC /MA</issuerName>
        <issuerTradingSymbol>CGI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001363853</rptOwnerCik>
            <rptOwnerName>Hawie John Weston</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>374 THOMPSON ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>THOMPSON</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06277</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr. Vice President &amp; CIO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-06-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>26395</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>36.7</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-06-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>200</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>36.7</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-06-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>10115</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>36.7</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Each share was converted into the right to receive $36.70 per share pursuant to the Agreement and Plan of Merger, dated as of October 30,2007, among The Commerce Group, Inc., Mapfre S.A. and Magellan Acquisition  Corp. (the &quot;Merger Agreement&quot;).</footnote>
        <footnote id="F2">200 shares are owned by the undersigned as custodian for the undersigned's son.</footnote>
        <footnote id="F3">The reporting person indirectly beneficially owns 10,115 shares that are held by the Employee Stock Ownership Plan of The Commerce Group, Inc., which number of shares is calculated based on the units that have been credited to the reporting person as a participant in the ESOP and is subject to adjustment from time to time due, in part, to the unit value and the price per share of the common stock.</footnote>
        <footnote id="F4">The filing of this statement by the undersigned is not to be construed as and shall not be deemed to be an admission that the undersigned is, for the purposes of Section 16 of the Securities Exchange Act of 1934, as amended, a beneficial owner of these shares.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/  John W. Hawie</signatureName>
        <signatureDate>2008-06-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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