<SEC-DOCUMENT>0001174947-24-000319.txt : 20240308
<SEC-HEADER>0001174947-24-000319.hdr.sgml : 20240308
<ACCEPTANCE-DATETIME>20240308113125
ACCESSION NUMBER:		0001174947-24-000319
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20240304
FILED AS OF DATE:		20240308
DATE AS OF CHANGE:		20240308

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Duchemin-Leslie Nadine
		CENTRAL INDEX KEY:			0001868265
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-00422
		FILM NUMBER:		24733026

	MAIL ADDRESS:	
		STREET 1:		239 WASHINGTON STREET
		CITY:			JERSEY CITY
		STATE:			NJ
		ZIP:			07302

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MIDDLESEX WATER CO
		CENTRAL INDEX KEY:			0000066004
		STANDARD INDUSTRIAL CLASSIFICATION:	WATER SUPPLY [4941]
		ORGANIZATION NAME:           	01 Energy & Transportation
		IRS NUMBER:				221114430
		STATE OF INCORPORATION:			NJ
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		485C ROUTE 1 SOUTH
		STREET 2:		SUITE 400
		CITY:			ISELIN
		STATE:			NJ
		ZIP:			08830
		BUSINESS PHONE:		7326341500

	MAIL ADDRESS:	
		STREET 1:		485C ROUTE 1 SOUTH
		STREET 2:		SUITE 400
		CITY:			ISELIN
		STATE:			NJ
		ZIP:			08830
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>ownership.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2024-03-04</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000066004</issuerCik>
        <issuerName>MIDDLESEX WATER CO</issuerName>
        <issuerTradingSymbol>MSEX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001868265</rptOwnerCik>
            <rptOwnerName>Duchemin-Leslie Nadine</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>485C ROUTE 1 SOUTH</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 400</rptOwnerStreet2>
            <rptOwnerCity>ISELIN</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>08830</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President &amp; CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock (Book Entry)</value>
            </securityTitle>
            <transactionDate>
                <value>2024-03-04</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4913</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>50.89</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4913</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock (Book Entry)</value>
            </securityTitle>
            <transactionDate>
                <value>2024-03-04</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2632</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>50.89</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2281</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents the number of shares released to the awardee after choosing to surrender shares back to Issuer to satisfy the tax withholding obligations that arose in connection with the vesting of the Restricted Stock.</footnote>
        <footnote id="F2">Amount withheld for tax withholding obligations that arose in connection with the vesting of the Restricted Stock.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>s/Jay L. Kooper, Power of Attorney for Nadine Duchemin-Leslie</signatureName>
        <signatureDate>2024-03-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
