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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2015-01-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001572303</rptOwnerCik>
            <rptOwnerName>Biddle Catherine U</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>53 ELMWOOD RD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SOUTH SALEM</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10590</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>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2015-01-02</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>58324</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">On January 2, 2015, the Issuer entered into an agreement with Willing L. Biddle, the Reporting Person's husband, and an officer and director of the Issuer, whereby Mr. Biddle was granted a restricted stock award of 2,500 shares of Class A Common Stock pursuant to the Issuer's Amended and Restated Restricted Stock Award Plan (the &quot;Restricted Stock Award Plan&quot;).</footnote>
        <footnote id="F2">This figure includes 37,500 restricted shares of Class A Common Stock issued to Mr. Biddle pursuant to the Restricted Stock Award Plan. On January 3, 2015, restrictions applicable to a previously reported grant to Mr. Biddle of 5,000 shares of Class A Common Stock lapsed, resulting in Mr. Biddle becoming fully vested in such shares. This resulted in no change in the number of shares beneficially owned by the Reporting Person.</footnote>
        <footnote id="F3">Mrs. Biddle is the direct beneficial owner of 2,769 shares of Class A Common Stock. She is the indirect beneficial owner of 55,555 shares of Class A Common Stock held as follows: 55,000 shares by Willing L. Biddle, including the 37,500 restricted shares referenced in Footnote 2, and 555 shares by the Catherine U. Biddle IRA for the benefit of Catherine U. Biddle.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Catherine U. Biddle by Thomas D. Myers as Attorney-in-Fact</signatureName>
        <signatureDate>2015-01-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
