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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>0001140361-10-015094.txt : 20100402
<SEC-HEADER>0001140361-10-015094.hdr.sgml : 20100402
<ACCEPTANCE-DATETIME>20100402140415
ACCESSION NUMBER:		0001140361-10-015094
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100401
FILED AS OF DATE:		20100402
DATE AS OF CHANGE:		20100402

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			PENNEY SHERRY H
		CENTRAL INDEX KEY:			0001210331

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14768
		FILM NUMBER:		10727715

	MAIL ADDRESS:	
		STREET 1:		90 ALBEE ROAD
		CITY:			BRAINTREE
		STATE:			MA
		ZIP:			02184

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NSTAR/MA
		CENTRAL INDEX KEY:			0001035675
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC SERVICES [4911]
		IRS NUMBER:				043466300
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		800 BOYLSTON ST
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199
		BUSINESS PHONE:		6174242000

	MAIL ADDRESS:	
		STREET 1:		800 BOYLSTON STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	B E C ENERGY
		DATE OF NAME CHANGE:	19980421

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BOSTON EDISON HOLDINGS
		DATE OF NAME CHANGE:	19970313
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-04-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001035675</issuerCik>
        <issuerName>NSTAR/MA</issuerName>
        <issuerTradingSymbol>NST</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001210331</rptOwnerCik>
            <rptOwnerName>PENNEY SHERRY H</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>800 BOYLSTON STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02199</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>Trustee</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2010-04-01</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1059</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>35.7187</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>27086.09</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Defererd Compensation Trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7726.58</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Includes shares acquired through the reinvestment of dividends in the NSTAR Dividend Reinvestment Plan for the periods 11/1/09 and 2/1/10</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Richard J. Morrison - Attorney in Fact for Sherry H. Penney</signatureName>
        <signatureDate>2010-04-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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