v3.26.1
Consolidated Statements of Stockholders' Equity - USD ($)
shares in Thousands, $ in Thousands
Total
Total Tetra Tech Equity
Common Stock
Additional Paid-in Capital
Accumulated Other Comprehensive Income (Loss)
Retained Earnings
Non-Controlling Interests
Beginning balance (in shares) at Sep. 29, 2024     267,717        
Beginning balance at Sep. 29, 2024 $ 1,830,413 $ 1,830,322 $ 2,677 $ 35,900 $ (78,875) $ 1,870,620 $ 91
Increase (Decrease) in Stockholders' Equity [Roll Forward]              
Net income 120,073 119,979       119,979 94
Foreign currency translation adjustments 13,791 13,791     13,791    
Net pension adjustments (33) (33)     (33)    
Distributions paid in noncontrolling interests (29)           (29)
Cash dividends (47,992) (47,992)       (47,992)  
Stock-based compensation 25,789 25,789   25,789      
Restricted & performance shares released (in shares)     475        
Restricted & performance shares released (13,942) (13,942) $ 6 (13,948)      
Stock options exercised (in shares)     35        
Stock options exercised 216 216   216      
Shares issued for Employee Stock Purchase Plan (in shares)     458        
Shares issued for Employee Stock Purchase Plan 15,307 15,307 $ 4 15,303      
Stock repurchases (in shares)     (5,933)        
Stock repurchases (201,497) (201,497) $ (59) (63,260)   (138,178)  
Ending balance (in shares) at Jun. 29, 2025     262,752        
Ending balance at Jun. 29, 2025 1,742,096 1,741,940 $ 2,628 0 (65,117) 1,804,429 156
Beginning balance (in shares) at Mar. 30, 2025     263,503        
Beginning balance at Mar. 30, 2025 1,573,781 1,573,658 $ 2,635 0 (153,180) 1,724,203 123
Increase (Decrease) in Stockholders' Equity [Roll Forward]              
Net income 113,883 113,844       113,844 39
Foreign currency translation adjustments 88,063 88,063     88,063    
Net pension adjustments 0            
Distributions paid in noncontrolling interests (6)           (6)
Cash dividends (17,092) (17,092)       (17,092)  
Stock-based compensation 8,762 8,762   8,762      
Restricted & performance shares released (in shares)     8        
Restricted & performance shares released (94) (94) $ 1 (95)      
Stock options exercised (in shares)     8        
Stock options exercised 45 45   45      
Stock repurchases (in shares)     (767)        
Stock repurchases (25,246) (25,246) $ (8) (8,712)   (16,526)  
Ending balance (in shares) at Jun. 29, 2025     262,752        
Ending balance at Jun. 29, 2025 1,742,096 1,741,940 $ 2,628 0 (65,117) 1,804,429 156
Beginning balance (in shares) at Sep. 28, 2025     261,418        
Beginning balance at Sep. 28, 2025 1,780,164 1,779,785 $ 2,614 0 (95,777) 1,872,948 379
Increase (Decrease) in Stockholders' Equity [Roll Forward]              
Net income 308,821 308,235       308,235 586
Foreign currency translation adjustments (9,697) (9,697)     (9,697)    
Net pension adjustments (305) (305)     (305)    
Distributions paid in noncontrolling interests (460)           (460)
Cash dividends (52,473) (52,473)       (52,473)  
Stock-based compensation 27,438 27,438   27,438      
Restricted & performance shares released (in shares)     521        
Restricted & performance shares released (12,481) (12,481) $ 5 (12,486)      
Stock options exercised (in shares)     68        
Stock options exercised 564 564 $ 1 563      
Shares issued for Employee Stock Purchase Plan (in shares)     429        
Shares issued for Employee Stock Purchase Plan 12,570 12,570 $ 4 12,566      
Stock repurchases (in shares)     (6,392)        
Stock repurchases (201,564) (201,564) $ (64) (28,081)   (173,419)  
Ending balance (in shares) at Jun. 28, 2026     256,044        
Ending balance at Jun. 28, 2026 1,852,577 1,852,072 $ 2,560 0 (105,779) 1,955,291 505
Beginning balance (in shares) at Mar. 29, 2026     259,525        
Beginning balance at Mar. 29, 2026 1,863,749 1,863,379 $ 2,595 0 (94,684) 1,955,468 370
Increase (Decrease) in Stockholders' Equity [Roll Forward]              
Net income 109,801 109,584       109,584 217
Foreign currency translation adjustments (11,095) (11,095)     (11,095)    
Net pension adjustments 0            
Distributions paid in noncontrolling interests (82)           (82)
Cash dividends (18,621) (18,621)       (18,621)  
Stock-based compensation 9,768 9,768   9,768      
Restricted & performance shares released (in shares)     4        
Restricted & performance shares released (51) (51)   (51)      
Stock options exercised (in shares)     12        
Stock options exercised 106 106   106      
Stock repurchases (in shares)     (3,497)        
Stock repurchases (100,998) (100,998) $ (35) (9,823)   (91,140)  
Ending balance (in shares) at Jun. 28, 2026     256,044        
Ending balance at Jun. 28, 2026 $ 1,852,577 $ 1,852,072 $ 2,560 $ 0 $ (105,779) $ 1,955,291 $ 505