<SEC-DOCUMENT>0001415889-22-011034.txt : 20221103
<SEC-HEADER>0001415889-22-011034.hdr.sgml : 20221103
<ACCEPTANCE-DATETIME>20221103110010
ACCESSION NUMBER:		0001415889-22-011034
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20221101
FILED AS OF DATE:		20221103
DATE AS OF CHANGE:		20221103

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Trent T McKenna
		CENTRAL INDEX KEY:			0001373205
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13011
		FILM NUMBER:		221356797

	BUSINESS ADDRESS:	
		STREET 1:		C/O COMFORT SYSTEMS USA, INC.
		STREET 2:		675 BERING DRIVE, SUITE 400
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77057
		BUSINESS PHONE:		713.830.9614

	MAIL ADDRESS:	
		STREET 1:		C/O COMFORT SYSTEMS USA, INC.
		STREET 2:		675 BERING DRIVE, SUITE 400
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77057

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COMFORT SYSTEMS USA INC
		CENTRAL INDEX KEY:			0001035983
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRICAL WORK [1731]
		IRS NUMBER:				760526487
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		675 BERING DRIVE
		STREET 2:		SUITE 400
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77057
		BUSINESS PHONE:		7138309600

	MAIL ADDRESS:	
		STREET 1:		675 BERING DRIVE
		STREET 2:		SUITE 400
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77057
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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        <issuerName>COMFORT SYSTEMS USA INC</issuerName>
        <issuerTradingSymbol>FIX</issuerTradingSymbol>
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            <rptOwnerName>Trent T McKenna</rptOwnerName>
        </reportingOwnerId>
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            <rptOwnerStreet1>C/O COMFORT SYSTEMS USA, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>675 BERING DRIVE, SUITE 400</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77057</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>EVP &amp; CHIEF OPERATING OFFICER</officerTitle>
            <otherText></otherText>
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                </transactionShares>
                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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                <transactionPricePerShare>
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    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option to Buy</value>
            </securityTitle>
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                <value>30.36</value>
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            <transactionDate>
                <value>2022-11-01</value>
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            <transactionAmounts>
                <transactionShares>
                    <value>2939</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2019-04-01</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2026-03-23</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2939</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
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                <sharesOwnedFollowingTransaction>
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        </derivativeTransaction>
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            <transactionDate>
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            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>1076</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2020-04-01</value>
                <footnoteId id="F3"/>
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            <expirationDate>
                <value>2027-03-08</value>
            </expirationDate>
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        </derivativeTransaction>
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                    <value>310</value>
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                <transactionPricePerShare>
                    <value>0</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <value>2021-04-01</value>
                <footnoteId id="F4"/>
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            <expirationDate>
                <value>2028-03-07</value>
            </expirationDate>
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        </derivativeTransaction>
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    <footnotes>
        <footnote id="F1">Represents the average price of shares sold; full information regarding the number of shares sold and specific prices will be made available upon request to the Company's Office of the General Counsel.</footnote>
        <footnote id="F2">Stock options were granted on 03/23/2016, vested ratably over a three-year period, and were fully vested on 04/01/2019.</footnote>
        <footnote id="F3">Stock options were granted on 03/08/2017, vested ratably over a three-year period, and were fully vested on 04/01/2020.</footnote>
        <footnote id="F4">Stock options were granted on 03/07/2018, vested ratably over a three-year period, and were fully vested on 04/01/2021.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Laura F. Howell, Attorney-in-Fact</signatureName>
        <signatureDate>2022-11-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
