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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>0001140361-09-030617.txt : 20091231
<SEC-HEADER>0001140361-09-030617.hdr.sgml : 20091231
<ACCEPTANCE-DATETIME>20091231092842
ACCESSION NUMBER:		0001140361-09-030617
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20091230
FILED AS OF DATE:		20091231
DATE AS OF CHANGE:		20091231

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Chalstrom Harry Pierson
		CENTRAL INDEX KEY:			0001352825

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14369
		FILM NUMBER:		091267610

	MAIL ADDRESS:	
		STREET 1:		222 SMALLWOOD VILLAGE CENTER
		CITY:			ST.CHARLES
		STATE:			MD
		ZIP:			20602

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AMERICAN COMMUNITY PROPERTIES TRUST
		CENTRAL INDEX KEY:			0001065645
		STANDARD INDUSTRIAL CLASSIFICATION:	LAND SUBDIVIDERS & DEVELOPERS (NO CEMETERIES) [6552]
		IRS NUMBER:				522058165
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		222 SMALLWOOD VILLAGE CENTER
		CITY:			ST. CHARLES
		STATE:			MD
		ZIP:			20602
		BUSINESS PHONE:		3018438600

	MAIL ADDRESS:	
		STREET 1:		222 SMALLWOOD VILLAGE CENTER
		CITY:			ST. CHARLES
		STATE:			MD
		ZIP:			20602
</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>2009-12-30</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001065645</issuerCik>
        <issuerName>AMERICAN COMMUNITY PROPERTIES TRUST</issuerName>
        <issuerTradingSymbol>APO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001352825</rptOwnerCik>
            <rptOwnerName>Chalstrom Harry Pierson</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>222 SMALLWOOD VILLAGE CENTER</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ST CHARLES</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>20602</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VICE PRESIDENT</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2009-12-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>100</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>7.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">(1) Converted into the right to receive $7.75 per share pursuant to the terms of that certain Agreement and Plan of Merger by and among the issuer, FCP/ACPT Acquisition Company, Inc. and FCP Fund I, L.P., dated as of September 25, 2009.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Harry Pierson Chalstrom</signatureName>
        <signatureDate>2009-12-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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