<SEC-DOCUMENT>0001207854-25-000004.txt : 20251120
<SEC-HEADER>0001207854-25-000004.hdr.sgml : 20251120
<ACCEPTANCE-DATETIME>20251120185115
ACCESSION NUMBER:		0001207854-25-000004
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20251118
FILED AS OF DATE:		20251120
DATE AS OF CHANGE:		20251120

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BATRACK DAN L
		CENTRAL INDEX KEY:			0001207854
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19655
		FILM NUMBER:		251504282

	MAIL ADDRESS:	
		STREET 1:		TETRA TECH, INC.
		STREET 2:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TETRA TECH INC
		CENTRAL INDEX KEY:			0000831641
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-ENGINEERING SERVICES [8711]
		ORGANIZATION NAME:           	07 Trade & Services
		EIN:				954148514
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0928

	BUSINESS ADDRESS:	
		STREET 1:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107
		BUSINESS PHONE:		6263514664

	MAIL ADDRESS:	
		STREET 1:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107
</SEC-HEADER>
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    <footnotes>
        <footnote id="F1">Amount of securities beneficially owned was updated to reflect that 149 shares of common stock were acquired by the Reporting Person on December 15, 2024, pursuant to the Tetra Tech, Inc. Employee Stock Purchase Plan (ESPP).</footnote>
        <footnote id="F2">Represents the shares withheld to pay the related tax liability of the restricted stock units (RSUs) that vested on November 18, 2025.</footnote>
        <footnote id="F3">Shares acquired pursuant to vesting of performance stock units earned under 2018 Equity Incentive Plan.</footnote>
        <footnote id="F4">Represents the shares withheld to pay the related tax liability of performance stock units that vested on November 18, 2025.</footnote>
        <footnote id="F5">Represents an award of restricted stock units (RSUs), each unit of which represents a contingent right to receive one share of Tetra Tech common stock.</footnote>
        <footnote id="F6">The RSUs become vested as to 25% of the shares on November 18, 2022, and 25% annually, thereafter, until fully vested.</footnote>
        <footnote id="F7">The RSUs are exercisable at the time of vesting and do not have a set expiration date.</footnote>
        <footnote id="F8">The RSUs become vested as to 25% of the shares on November 18, 2023, and 25% annually, thereafter, until fully vested.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Preston Hopson, Attorney-in-fact for Dan L. Batrack</signatureName>
        <signatureDate>2025-11-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</DOCUMENT>
</SEC-DOCUMENT>
