Earnings per Share ("EPS") (Tables)

6 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Schedule of number of weighted-average shares used to compute basic and diluted EPS

The following table presents the number of weighted-average shares used to compute basic and diluted EPS (in thousands, except per share data):

	Three Months Ended				Six Months Ended
	March 31, 2024		April 2, 2023		March 31, 2024		April 2, 2023
Net income attributable to Tetra Tech	$	76,446	$	42,830	$	151,418	$	159,536
Weighted-average common shares outstanding – basic	53,484		53,227		53,419		53,165
Effect of dilutive stock options and unvested restricted stock	391		400		406		430
Weighted-average common shares outstanding – diluted	53,875		53,627		53,825		53,595
Earnings per share attributable to Tetra Tech:
Basic	$	1.43	$	0.80	$	2.83	$	3.00
Diluted	$	1.42	$	0.80	$	2.81	$	2.98