<SEC-DOCUMENT>0001415889-25-020711.txt : 20250731
<SEC-HEADER>0001415889-25-020711.hdr.sgml : 20250731
<ACCEPTANCE-DATETIME>20250731153643
ACCESSION NUMBER:		0001415889-25-020711
CONFORMED SUBMISSION TYPE:	144
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20250731
DATE AS OF CHANGE:		20250731

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COMFORT SYSTEMS USA INC
		CENTRAL INDEX KEY:			0001035983
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRICAL WORK [1731]
		ORGANIZATION NAME:           	05 Real Estate & Construction
		EIN:				760526487
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		144
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	001-13011
		FILM NUMBER:		251171381

	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

REPORTING-OWNER:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Trent T McKenna
		CENTRAL INDEX KEY:			0001373205
		ORGANIZATION NAME:           	
		EIN:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		144

	MAIL ADDRESS:	
		STREET 1:		C/O COMFORT SYSTEMS USA, INC.
		STREET 2:		675 BERING DRIVE, SUITE 400
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77057
</SEC-HEADER>
<DOCUMENT>
<TYPE>144
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
	<headerData>
        <submissionType>144</submissionType>
                <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001373205</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
        <liveTestFlag>LIVE</liveTestFlag>




                </filerInfo>
    </headerData>

     <formData>
        <issuerInfo>
            <issuerCik>0001035983</issuerCik>
			<issuerName>COMFORT SYSTEMS USA INC</issuerName>


			    <secFileNumber>001-13011</secFileNumber>


			<issuerAddress>
				<com:street1>675 BERING DRIVE</com:street1>
                				<com:street2>SUITE 400</com:street2>
                				<com:city>HOUSTON</com:city>
				<com:stateOrCountry>TX</com:stateOrCountry>
				<com:zipCode>77057</com:zipCode>
			</issuerAddress>

			<issuerContactPhone>7138309600</issuerContactPhone>
			<nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Trent T. McKenna</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>

			<relationshipsToIssuer>

				    <relationshipToIssuer>Officer</relationshipToIssuer>

			</relationshipsToIssuer>
		</issuerInfo>

				          <securitiesInformation>
			<securitiesClassTitle>Common</securitiesClassTitle>
			<brokerOrMarketmakerDetails>
				<name>Fidelity Brokerage Services LLC</name>
				<address>
				<com:street1>245 Summer Street</com:street1>
                				<com:city>Boston, </com:city>
				<com:stateOrCountry>MA</com:stateOrCountry>
				<com:zipCode>02110</com:zipCode>
				</address>
			</brokerOrMarketmakerDetails>
			<noOfUnitsSold>4400</noOfUnitsSold>
			<aggregateMarketValue>3153159.52</aggregateMarketValue>
			<noOfUnitsOutstanding>35281452</noOfUnitsOutstanding>
			<approxSaleDate>07/31/2025</approxSaleDate>
			<securitiesExchangeName>NYSE</securitiesExchangeName>
		</securitiesInformation>

    		       <securitiesToBeSold>
         <securitiesClassTitle>Common</securitiesClassTitle>
         <acquiredDate>04/01/2024</acquiredDate>
         <natureOfAcquisitionTransaction>Equity Compensation</natureOfAcquisitionTransaction>
                  <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
                  <isGiftTransaction>N</isGiftTransaction>
		          <amountOfSecuritiesAcquired>1781</amountOfSecuritiesAcquired>
                  <paymentDate>04/01/2024</paymentDate>
                  <natureOfPayment>Equity Compensation</natureOfPayment>
      </securitiesToBeSold>
             <securitiesToBeSold>
         <securitiesClassTitle>Common</securitiesClassTitle>
         <acquiredDate>03/20/2024</acquiredDate>
         <natureOfAcquisitionTransaction>Equity Compensation</natureOfAcquisitionTransaction>
                  <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
                  <isGiftTransaction>N</isGiftTransaction>
		          <amountOfSecuritiesAcquired>902</amountOfSecuritiesAcquired>
                  <paymentDate>03/20/2024</paymentDate>
                  <natureOfPayment>Equity Compensation</natureOfPayment>
      </securitiesToBeSold>
             <securitiesToBeSold>
         <securitiesClassTitle>Common</securitiesClassTitle>
         <acquiredDate>04/03/2023</acquiredDate>
         <natureOfAcquisitionTransaction>Equity Compensation</natureOfAcquisitionTransaction>
                  <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
                  <isGiftTransaction>N</isGiftTransaction>
		          <amountOfSecuritiesAcquired>1717</amountOfSecuritiesAcquired>
                  <paymentDate>04/03/2023</paymentDate>
                  <natureOfPayment>Equity Compensation</natureOfPayment>
      </securitiesToBeSold>

    <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>



        <noticeSignature>
            <noticeDate>07/31/2025</noticeDate>
                        <signature>  /s/ Trent McKenna</signature>
        </noticeSignature>
	</formData>
    </edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
