<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-01-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001029800</issuerCik>
        <issuerName>URSTADT BIDDLE PROPERTIES INC</issuerName>
        <issuerTradingSymbol>UBA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001070094</rptOwnerCik>
            <rptOwnerName>BIDDLE WILLING L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>53 ELMWOOD ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SOUTH SALEM</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10590</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2016-01-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>16250</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>44574</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2016-01-22</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F2"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6250</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>38324</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">On January 21, 2016, Willing L. Biddle (the &quot;Reporting Person&quot;) sold 16,250 shares of Class A Common Stock to Urstadt Property Company, Inc. (&quot;UPCO&quot;), a Delaware corporation, of which the Issuer's Chairman, Charles J. Urstadt, is Chairman and a controlling shareholder, in a private transaction.</footnote>
        <footnote id="F2">On January 22, 2016, the Reporting Person sold 6,250 shares of Class A Common Stock to UPCO, in a private transaction.</footnote>
        <footnote id="F3">This figure includes 35,000 restricted shares of Class A Common Stock issued pursuant to the Issuer's Amended and Restated Restricted Stock Award Plan.</footnote>
        <footnote id="F4">Mr. Biddle is the direct beneficial owner of 35,000 shares of Class A Common Stock, comprised of the 35,000 restricted shares referenced in Footnote 3.  In addition, he is the indirect beneficial owner of 3,324 shares of Class A Common Stock, of which 2,769 shares are owned beneficially and of record by Catherine U. Biddle, the Reporting Person's wife, and 555 shares are owned by the Catherine U. Biddle IRA for the benefit of Catherine U. Biddle.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Willing L. Biddle by Thomas D. Myers as Attorney-in-Fact</signatureName>
        <signatureDate>2016-01-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
