-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 Sd9pmNuFl8YiPRq2PfH1ON0HLZzH5bHWYcgxdSre4pU70TaSQJzDYHfEu78OKHM4
 xUoi56enKvmWM0rOJqtn1g==

<SEC-DOCUMENT>0001179110-11-000717.txt : 20110106
<SEC-HEADER>0001179110-11-000717.hdr.sgml : 20110106
<ACCEPTANCE-DATETIME>20110106095812
ACCESSION NUMBER:		0001179110-11-000717
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110106
FILED AS OF DATE:		20110106
DATE AS OF CHANGE:		20110106

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			AUMILLER ROBERT J
		CENTRAL INDEX KEY:			0001242130

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-23090
		FILM NUMBER:		11513006

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CARROLLTON BANCORP
		CENTRAL INDEX KEY:			0000859222
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				521660951
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1205

	BUSINESS ADDRESS:	
		STREET 1:		7151 COLUMBIA GATEWAY DRIVE, SUITE A
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21046
		BUSINESS PHONE:		(410) 312-5400

	MAIL ADDRESS:	
		STREET 1:		7151 COLUMBIA GATEWAY DRIVE, SUITE A
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21046
</SEC-HEADER>
<DOCUMENT>
<TYPE>5
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 5 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>5</documentType>

    <periodOfReport>2011-01-06</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <form3HoldingsReported>0</form3HoldingsReported>

    <form4TransactionsReported>0</form4TransactionsReported>

    <issuer>
        <issuerCik>0000859222</issuerCik>
        <issuerName>CARROLLTON BANCORP</issuerName>
        <issuerTradingSymbol>CRRB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001242130</rptOwnerCik>
            <rptOwnerName>AUMILLER ROBERT J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>315 WEST WIND ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TOWSON</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>21204</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-02-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>5.579</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>13381</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Owned jointly with wife</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Robert J. Aumiller</signatureName>
        <signatureDate>2011-01-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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