<?xml version="1.0"?>
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    <periodOfReport>2021-01-07</periodOfReport>

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    <issuer>
        <issuerCik>0000098246</issuerCik>
        <issuerName>TIFFANY &amp; CO</issuerName>
        <issuerTradingSymbol>TIF</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
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            <rptOwnerCik>0001730584</rptOwnerCik>
            <rptOwnerName>Davey Andrea</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>TIFFANY &amp; CO.</rptOwnerStreet1>
            <rptOwnerStreet2>200 FIFTH AVENUE</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10010</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isOfficer>1</isOfficer>
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            <isOther>0</isOther>
            <officerTitle>Senior Vice President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
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                <transactionPricePerShare>
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    <footnotes>
        <footnote id="F1">Disposed of pursuant to the Amended and Restated Agreement and Plan of Merger, dated as of October 28, 2020, by and among Tiffany &amp; Co. (the &quot;Company&quot;), LVMH Moet Hennessy-Louis Vuitton SE (&quot;Parent&quot;), Breakfast Holdings Acquisition Corp. (&quot;Holding&quot;) and Breakfast Acquisition Corp. (&quot;Merger Sub&quot;) (the &quot;Merger Agreement&quot;), which amended and restated the Agreement and Plan of Merger, dated as of November 24, 2019, by and among the Company, Parent, Holding and Merger Sub, in exchange for $131.50 per share in cash, without interest and less any required withholding taxes (the &quot;Per Share Merger Consideration&quot;).</footnote>
        <footnote id="F2">Pursuant to the Merger Agreement, each outstanding performance-based restricted stock unit was canceled and converted into the right to receive an amount in cash, without interest and less any required withholding taxes, equal to the product of (i) the total number of shares subject to such performance-based restricted stock unit (including for the avoidance of doubt any dividend equivalent units credited in respect of such performance-based restricted stock unit), multiplied by (ii) the Per Share Merger Consideration.</footnote>
        <footnote id="F3">Pursuant to the Merger Agreement, each outstanding restricted stock unit was canceled and converted into the right to receive an amount in cash, without interest and less any required withholding taxes, equal to the product of (i) the total number of shares subject to such restricted stock unit (including for the avoidance of doubt any dividend equivalent units credited in respect of such restricted stock unit), multiplied by (ii) the Per Share Merger Consideration.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Catherine W.H. So, Attorney-in-Fact</signatureName>
        <signatureDate>2021-01-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0306
4
2021-01-07
1
0000098246
TIFFANY & CO
TIF
0001730584
Davey Andrea
TIFFANY & CO.
200 FIFTH AVENUE
NEW YORK
NY
10010
0
1
0
0
Senior Vice President
Common Stock $.01 Par
2021-01-07
4
D
0
15942
131.50
D
0
D
Performance-based Restricted Stock Unit
2021-01-07
4
D
0
4241
D
Common Stock $.01 Par
4241.0
0
D
Restricted Stock Units
2021-01-07
4
D
0
3961
D
Common Stock $.01 Par
3961.0
0
D
Disposed of pursuant to the Amended and Restated Agreement and Plan of Merger, dated as of October 28, 2020, by and among Tiffany & Co. (the "Company"), LVMH Moet Hennessy-Louis Vuitton SE ("Parent"), Breakfast Holdings Acquisition Corp. ("Holding") and Breakfast Acquisition Corp. ("Merger Sub") (the "Merger Agreement"), which amended and restated the Agreement and Plan of Merger, dated as of November 24, 2019, by and among the Company, Parent, Holding and Merger Sub, in exchange for $131.50 per share in cash, without interest and less any required withholding taxes (the "Per Share Merger Consideration").
Pursuant to the Merger Agreement, each outstanding performance-based restricted stock unit was canceled and converted into the right to receive an amount in cash, without interest and less any required withholding taxes, equal to the product of (i) the total number of shares subject to such performance-based restricted stock unit (including for the avoidance of doubt any dividend equivalent units credited in respect of such performance-based restricted stock unit), multiplied by (ii) the Per Share Merger Consideration.
Pursuant to the Merger Agreement, each outstanding restricted stock unit was canceled and converted into the right to receive an amount in cash, without interest and less any required withholding taxes, equal to the product of (i) the total number of shares subject to such restricted stock unit (including for the avoidance of doubt any dividend equivalent units credited in respect of such restricted stock unit), multiplied by (ii) the Per Share Merger Consideration.
/s/ Catherine W.H. So, Attorney-in-Fact
2021-01-11