Form 8-K

8-K — TETRA TECH INC

Accession: 0001104659-26-125600

Filed: 2026-11-12

Period: 2026-11-11

CIK: 0000831641

SIC: 8711 (SERVICES-ENGINEERING SERVICES)

Item: Results of Operations and Financial Condition

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — tm2629545d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2629545d1_ex99-1.htm)

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8-K (Primary)

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0000831641

2026-11-11

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of

the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):

November

11, 2026

TETRA

TECH, INC.

(Exact name of registrant as specified in its

charter)

Delaware

0-19655

95-4148514

(State

or other jurisdiction

of incorporation)

(Commission

File Number)

(IRS Employer

Identification Number)

3475

East Foothill Boulevard, Pasadena,

California 91107

(Address of principal executive office, including zip code)

(626) 351-4664

(Registrant’s telephone number, including

area code)

Not Applicable

(Former name or former address, if changed since

last report)

Check the appropriate box below if the Form 8-K

filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨ Written

communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting

material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement

communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement

communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b)

of the Act:

Title

of each class

Trading

symbol(s)

Name

of each exchange on which registered

Common

Stock, $0.01 par value

TTEK

The

Nasdaq Stock Market LLC

Indicate by check mark whether the registrant

is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2

of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging

Growth Company ¨

an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying

with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item 2.02. Results of Operations and Financial Condition.

On November 11, 2026,

Tetra Tech, Inc. (“Tetra Tech”) reported its financial results for the fourth fiscal quarter ended September 27,

2026. A copy of the press release is attached to this report as Exhibit 99.1.

Exhibit 99.1 attached

hereto shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, nor

shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended.

Item 8.01. Other Events.

On November 11, 2026,

Tetra Tech announced that its Board of Directors has declared a $0.072 per share quarterly cash dividend. The dividend is payable on December 11,

2026 to stockholders of record as of the close of business on December 2, 2026.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits

99.1 Press Release, dated November 11, 2026, reporting the financial results for Tetra Tech’s fourth

fiscal quarter ended September 27, 2026, and the declaration of a quarterly cash dividend.

104 Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements

of the Securities Exchange Act of 1934, Tetra Tech has duly caused this report to be signed on its behalf by the undersigned hereunto

duly authorized.

TETRA TECH, INC.

Date:

November 11, 2026

By:

/s/

ROGER R. ARGUS

Roger R. Argus

Chief Executive Officer and President

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2629545d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

NEWS

RELEASE

November 11, 2026

Tetra Tech Reports

Strong Fourth Quarter and Fiscal Year 2026 Results

· Fourth

quarter revenue $1.34 billion and net revenue $1.15 billion

· Record

fourth quarter EPS $0.51 and adjusted EPS $0.49

· Record

fiscal year EPS $1.69 and adjusted EPS $1.60

· Backlog

$4.67 billion, up 13% Y/Y

Pasadena, California.

Tetra Tech, Inc. (NASDAQ: TTEK), a global provider of high-end technical and engineering services, Leading

with Science® in water, environment and sustainable infrastructure,

today announced results for the fourth quarter and fiscal year ended September 27, 2026.

Fourth Quarter

Results

Revenue and revenue,

net of subcontractor costs (net revenue)1, in the fourth quarter totaled $1.34 billion and $1.15 billion, respectively.

Net revenue increased 5% year-over-year excluding episodic disaster response. Operating income was $188 million and adjusted EBITDA1

was $194 million; adjusted EBITDA margin increased 90 basis points year-over-year. EPS was $0.51 and adjusted EPS1 was $0.49,

up 9% year-over-year. Backlog was $4.67 billion at the end of the fourth quarter, up 13% year-over-year.

Recent Key Wins

· $1.4

billion multiple-award blanket purchase agreement for enterprise logistics services for

NASA

· $145

million multiple-award contract for engineering and technical consulting services for

U.S. Navy

· $141

million single-award contract for water infrastructure assessment services for U.S. EPA

· $85

million multiple-award contracts for environmental services for USACE Europe District

· $63

million single-award contract for emergency preparedness and response services for U.S.

EPA

· $49

million multiple-award contract for geospatial and engineering services for NOAA

· $14

million single-award contract for digital systems modernization for LA Metro

· $12.7

million single-award contracts for technical services for Millennium Challenge Corporation

1 Non-GAAP

financial measures which the Company believes provide valuable perspectives on its business

results. Refer to Regulation G Information for reconciliations to the comparable GAAP metrics.

Executive Management Comments

Roger Argus, Chief

Executive Officer, commented, “We completed fiscal year 2026 with a strong fourth quarter driven by our global commercial and government

businesses. We continue to see increasing demand for our differentiated Leading with Science®

technical services for water and environmental programs, including digital automation for associated facilities. Our resilient

infrastructure design services are growing globally with new contracts for water supply, coastal infrastructure, and defense modernization.

These key client programs drove our backlog up by more than $530 million, an increase of 13% from last year. This strong momentum in

backlog gives us confidence in continued revenue growth and further margin expansion.”

Steve Burdick,

Chief Financial Officer, stated, “In fiscal year 2026, we continued to increase our profit margins with 90 basis points of EBITDA

margin expansion from fiscal year 2025. The strength of our balance sheet and consistent cash flow generation position us to continue

to invest in organic growth and strategic acquisitions.”

Quarterly Dividend

and Share Repurchase Program

On November 9,

2026, Tetra Tech’s Board of Directors approved a quarterly dividend in the amount of $0.072 per share, an 11% increase year-over-year,

payable on December 11, 2026, to stockholders of record as of December 2, 2026. This is the 46th consecutive double-digit

increase in the Company’s quarterly dividend. In the fourth quarter of fiscal year 2026, Tetra Tech repurchased $100 million of

common stock. Additionally, as of September 27, 2026, the Company had $798 million remaining under its share repurchase program.

Fiscal Year Results

Revenue for fiscal

year 2026 was $5.08 billion and net revenue was $4.35 billion. For fiscal year 2026, net revenue increased 7% compared to last year excluding

USAID / DOS and episodic disaster response. Operating income was $619 million, adjusted EBITDA was $660 million with margin up 90 basis

points compared to last year, and EPS was $1.69. Cash flows generated from operations were up 14% year-over-year.

Business Outlook

The following statements

are based on current expectations. These statements are forward-looking, and the actual results could differ materially. These statements

do not include the potential impact of transactions that may be completed or developments that become evident after the date of this

release. The Business Outlook section should be read in conjunction with the information on forward-looking statements at the end of

this release.

Tetra Tech expects

EPS for the first quarter of fiscal year 2027 to range from $0.36 to $0.38 and net revenue2 to range from $1.04 billion

to $1.08 billion. For fiscal year 2027, Tetra Tech expects EPS to range from $1.65 to $1.80, and net revenue to range from $4.425 billion

to $4.625 billion.

Webcast

Investors will

have the opportunity to access a live audio-visual webcast and supplemental financial information concerning the fourth quarter and fiscal

year 2026 results through a link posted on the Company’s website at tetratech.com on November 12, 2026, at 8:00 a.m. (PT).

2 Reconciliation of the net revenue guidance to the most directly

comparable GAAP measure is not available without unreasonable efforts because the Company cannot predict the magnitude and timing of

all the components required to provide such reconciliation with sufficient precision.

About Tetra

Tech

Tetra

Tech is the leader in water, environment and sustainable infrastructure, providing high-end technical and engineering services for projects

worldwide. With more than 25,000 employees working together, Tetra Tech provides clear solutions to complex problems by Leading

with Science® to address the entire water cycle, protect and restore the environment, and design sustainable

and resilient infrastructure. For more information about Tetra Tech, please visit tetratech.com

or follow us on LinkedIn and Facebook.

CONTACTS:

Jim Wu, Investor Relations

Charlie MacPherson, Media & Public Relations

(626) 470-2844

Forward-Looking

Statements

This release

contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. The use of words such

as "anticipate," "expect," "could," "may," "intend," "plan" and "believe,"

among others, generally identify forward-looking statements. These forward-looking statements are based on current expectations and beliefs

of Tetra Tech’s management and currently available operating, financial, economic and other information, and are subject to a number

of risks and uncertainties. Readers are cautioned that these forward-looking statements are only predictions and may differ materially

from actual future events or results. A variety of factors, many of which are beyond our control, could cause actual future results or

events to differ materially from those projected in the forward-looking statements in this release, including but not limited to: continuing

worldwide political and economic uncertainties; the U.S. Administration’s potential changes to fiscal policies; the cyclicality

in demand for our overall services; the fluctuation in demand for oil and gas, and mining services; risks related to international operations;

concentration of revenues from U.S. government agencies and potential funding disruptions by these agencies; dependence on winning or

renewing U.S. government contracts; the delay or unavailability of public funding on U.S. government contracts; the U.S. government’s

right to modify, delay, curtail or terminate contracts at its convenience; compliance with government procurement laws and regulations;

the impact of global pandemics; credit risks associated with certain clients in certain geographic areas or industries; acquisition strategy

and integration risks; goodwill or other intangible asset impairment; the failure to comply with worldwide anti-bribery laws; the failure

to comply with domestic and international export laws; the failure to properly manage projects; the loss of key personnel or the inability

to attract and retain qualified personnel; the ability of our employees to obtain government granted eligibility; the use of estimates

and assumptions in the preparation of financial statements; the ability to maintain adequate workforce utilization; the use of the percentage-of-completion

method of accounting; the inability to accurately estimate and control contract costs; the failure to adequately recover on our claims

for additional contract costs; the failure to win or renew contracts with private and public sector clients; growth strategy management;

backlog cancellation and adjustments; risks relating to cyber security breaches; the failure of partners to perform on joint projects;

the failure of subcontractors to satisfy their obligations; requirements to pay liquidated damages based on contract performance; the

adoption of new legal requirements; changes in resource management, environmental or infrastructure industry laws, regulations or programs;

changes in bank and capital markets and the access to capital; credit agreement covenants; industry competition; liability related to

legal proceedings, investigations, and disputes; the availability of third-party insurance coverage; the ability to obtain adequate bonding;

employee, agent, or partner misconduct; employee risks related to international travel; safety programs; conflict of interest issues;

liabilities relating to reports and opinions; liabilities relating to environmental laws and regulations; force majeure events; protection

of intellectual property rights; stock price volatility; the ability to impede a business combination based on Delaware law and charter

documents; and other risks and uncertainties as may be described in Tetra Tech’s periodic filings with the Securities and Exchange

Commission, including those described in the “Risk Factors” section of Tetra Tech’s Annual Report on Form 10-K

for the fiscal year ended September 28, 2025. Readers should not place undue reliance on forward-looking statements since such information

speaks only as of the date of this release. Tetra Tech does not intend to update forward-looking statements and expressly disclaims any

obligation to do so.

Non-GAAP

Financial Measures

To supplement

the financial results presented in accordance with generally accepted accounting principles in the United States (“GAAP”),

we present certain non-GAAP financial measures within the meaning of Regulation G under the Securities Exchange Act of 1934, as amended.

We provide these non-GAAP financial measures because we believe they provide a valuable perspective on our financial results. However,

non-GAAP measures have limitations as analytical tools and should not be considered in isolation and are not in accordance with, or a

substitute for, GAAP measures. In addition, other companies may define non-GAAP measures differently which limits the ability of investors

to compare non-GAAP measures of Tetra Tech to those used by our peer companies. A reconciliation of these non-GAAP financial measures

to the most directly comparable GAAP financial measures is set forth in this release.

Tetra Tech, Inc.

Consolidated Balance Sheets

(unaudited - in thousands, except par value)

September 27,

September 28,

2026

2025

Assets

Current assets:

Cash and cash equivalents

$ 235,076

$ 167,459

Accounts receivable, net

1,149,139

1,158,928

Contract assets

144,924

138,232

Prepaid expenses and other current assets

112,440

83,434

Assets held-for-sale

57,502

Income taxes receivable

55,234

15,334

Total current assets

1,696,813

1,620,889

Property and equipment, net

65,507

66,148

Right-of-use assets, operating leases

191,373

197,618

Goodwill

2,224,991

2,049,874

Intangible assets, net

116,417

121,160

Deferred tax assets

40,641

106,238

Other non-current assets

140,057

120,247

Total assets

$ 4,475,799

$ 4,282,174

Liabilities and Equity

Current liabilities:

Accounts payable

$ 223,810

$ 204,725

Accrued compensation

325,294

346,912

Contract liabilities

406,937

420,254

Short-term lease liabilities, operating leases

77,958

69,099

Current contingent earn-out liabilities

49,352

24,826

Liabilities held-for-sale

25,115

Other current liabilities

259,113

288,113

Total current liabilities

1,342,464

1,379,044

Deferred tax liabilities

18,964

21,333

Long-term debt

891,957

763,363

Long-term lease liabilities, operating leases

134,999

154,695

Non-current contingent earn-out liabilities

43,581

32,135

Other non-current liabilities

159,503

151,440

Total liabilities

2,591,468

2,502,010

Equity:

Preferred stock - authorized, 2,000 shares of $0.01 par value; no shares issued

and outstanding at September 27, 2026 and September 28, 2025

Common stock - authorized, 750,000 shares of $0.01 par value; issued

and outstanding, 253,284 and 261,418 shares at September 27, 2026 and September 28, 2025, respectively

2,533

2,614

Accumulated other comprehensive loss

(96,442 )

(95,777 )

Retained earnings

1,977,557

1,872,948

Tetra Tech stockholders' equity

1,883,648

1,779,785

Noncontrolling interests

683

379

Total stockholders' equity

1,884,331

1,780,164

Total liabilities and stockholders' equity

$ 4,475,799

$ 4,282,174

Tetra Tech, Inc.

Consolidated Statements of Income

(unaudited - in thousands, except per share data)

Three Months Ended

Fiscal Year Ended

September 27,

September 28,

September 27,

September 28,

2026

2025

2026

2025

Revenue

$ 1,337,362

$ 1,330,100

$ 5,076,737

$ 5,442,590

Subcontractor costs

(184,391 )

(166,791 )

(728,399 )

(825,230 )

Other costs of revenue

(887,084 )

(889,163 )

(3,404,785 )

(3,656,016 )

Gross profit

265,887

274,146

943,553

961,344

Selling, general and administrative expenses

(84,438 )

(102,714 )

(339,092 )

(357,737 )

Legal contingency costs

(115,000 )

Impairment of goodwill

(92,416 )

Contingent consideration - fair value adjustments

6,991

9,873

14,421

12,228

Income from operations

188,440

181,305

618,882

408,419

Interest expense, net

(7,345 )

(6,806 )

(30,468 )

(30,802 )

Other non-operating income

12,361

Income before income tax expense

181,095

174,499

600,775

377,617

Income tax expense

(49,187 )

(46,623 )

(160,046 )

(129,668 )

Net income

131,908

127,876

440,729

247,949

Net income attributable to noncontrolling interests

(185 )

(131 )

(771 )

(225 )

Net income attributable to Tetra Tech

$ 131,723

$ 127,745

$ 439,958

$ 247,724

Earnings per share attributable to Tetra Tech:

Basic

$ 0.52

$ 0.49

$ 1.70

$ 0.94

Diluted

$ 0.51

$ 0.48

$ 1.69

$ 0.93

Weighted-average common shares outstanding:

Basic

254,764

262,184

258,430

264,713

Diluted

256,663

264,247

260,235

267,123

Cash dividends paid per share

0.072

0.065

0.274

0.246

Tetra Tech, Inc.

Consolidated Statements of Cash Flows

(unaudited - in thousands)

Fiscal Year Ended

September 27,

September 28,

2026

2025

Cash flows from operating activities:

Net income

$ 440,729

$ 247,949

Adjustments to reconcile net income to net cash provided by operating activities:

Depreciation and amortization

56,294

58,276

Amortization of stock-based awards

36,561

33,946

Deferred income taxes

64,254

(11,297 )

Provision for losses on accounts receivables

1,889

3,150

Impairment of goodwill

92,416

Gain on sale of divested business

(12,361 )

Fair value adjustments to contingent consideration

(14,421 )

(12,228 )

Other non-cash items

2,936

9,024

Changes in operating assets and liabilities, net of effects of business acquisitions and divestitures:

Accounts receivable and contract assets

45,087

(112,755 )

Prepaid expenses and other assets

(9,719 )

(30,563 )

Accounts payable

10,118

2,398

Accrued compensation

(28,481 )

18,879

Contract liabilities

(13,836 )

73,489

Cash settled contingent earn-out liability

(11,170 )

Income taxes receivable/payable

(40,765 )

23,227

Other liabilities

(15,266 )

72,944

Net cash provided by operating activities

523,019

457,685

Cash flows from investing activities:

Payments for business acquisitions, net of cash acquired

(191,870 )

(97,263 )

Capital expenditures

(20,485 )

(18,633 )

Proceeds from sales of assets

915

919

Proceeds from company-owned life insurance policies

1,934

Proceeds from divested business, net

40,263

2,406

Proceeds from loan repayment from divested business

3,883

Net cash used in investing activities

(171,177 )

(106,754 )

Cash flows from financing activities:

Proceeds from borrowings

335,000

715,000

Repayments on long-term debt

(210,000 )

(771,027 )

Payment of debt issuance costs

(2,738 )

Repurchases of common stock

(302,010 )

(249,984 )

Shares repurchased for tax withholdings on share-based awards

(12,568 )

(14,047 )

Payments of contingent earn-out liabilities

(20,841 )

(15,055 )

Stock options exercised

1,394

469

Dividends paid

(70,827 )

(65,039 )

Principal payments on finance leases

(8,024 )

(7,823 )

Net cash used in financing activities

(287,876 )

(410,244 )

Effect of exchange rate changes on cash and cash equivalents

2,738

(5,004 )

Net increase (decrease) in cash and cash equivalents

66,704

(64,317 )

Cash and cash equivalents at beginning of year

168,372

232,689

Cash and cash equivalents at end of year

$ 235,076

$ 168,372

Tetra Tech, Inc.

Regulation G Information

September 27, 2026

Reconciliation of Revenue to Revenue, Net of Subcontractor Costs ("Net Revenue")

(in millions)

2025

2026

2023

2024

1st

Qtr

2nd

Qtr

Mos

3rd

Qtr

Mos

4th

Qtr

Total

1st

Qtr

2nd

Qtr

Mos

3rd

Qtr

Mos

4th

Qtr

Total

Consolidated

Revenue

4,522.6

5,198.7

1,420.6

1,322.1

2,742.7

1,369.8

4,112.5

1,330.1

5,442.6

1,210.7

1,220.2

2,430.8

1,308.6

3,739.4

1,337.3

5,076.7

Subcontractor

Costs

(771.5 )

(876.8 )

(223.3 )

(218.4 )

(441.7 )

(216.8 )

(658.5 )

(166.8 )

(825.3 )

(173.5 )

(170.5 )

(344.0 )

(200.0 )

(544.0 )

(184.4 )

(728.4 )

Net Revenue

3,751.1

4,321.9

1,197.3

1,103.7

2,301.0

1,153.0

3,454.0

1,163.3

4,617.3

1,037.2

1,049.7

2,086.8

1,108.6

3,195.4

1,152.9

4,348.3

GSG

Segment

Revenue

2,300.7

2,624.2

791.4

698.9

1,490.2

709.4

2,199.6

628.9

2,828.6

525.5

559.4

1,084.9

598.4

1,683.3

627.8

2,311.1

Subcontractor

Costs

(484.3 )

(540.5 )

(144.0 )

(134.6 )

(278.5 )

(136.8 )

(415.3 )

(88.4 )

(503.7 )

(93.4 )

(100.9 )

(194.3 )

(124.1 )

(318.4 )

(115.2 )

(433.6 )

Net Revenue

1,816.4

2,083.7

647.4

564.3

1,211.7

572.6

1,784.3

540.5

2,324.9

432.1

458.5

890.6

474.3

1,364.9

512.6

1,877.5

CIG

Segment

Revenue

2,292.7

2,634.4

644.9

637.8

1,282.6

676.6

1,959.1

721.2

2,680.2

704.2

676.2

1,380.3

728.3

2,108.6

729.5

2,838.1

Subcontractor

Costs

(358.0 )

(396.2 )

(94.9 )

(98.3 )

(193.2 )

(96.1 )

(289.4 )

(98.3 )

(387.7 )

(99.1 )

(85.0 )

(184.1 )

(94.1 )

(278.1 )

(89.2 )

(367.3 )

Net Revenue

1,934.7

2,238.2

550.0

539.5

1,089.4

580.5

1,669.7

622.9

2,292.5

605.1

591.2

1,196.2

634.2

1,830.5

640.3

2,470.8

Reconciliation of Net Income Attributable to Tetra Tech to Adjusted EBITDA

(in thousands)

2025

2026

2023

2024

1st

Qtr

2nd

Qtr

Mos

3rd

Qtr

Mos

4th

Qtr

Total

1st

Qtr

2nd

Qtr

Mos

3rd

Qtr

Mos

4th

Qtr

Total

Net Income Attributable to Tetra

Tech

273,420

333,382

747

5,388

6,135

113,844

119,979

127,745

247,724

105,028

93,623

198,651

109,584

308,235

131,723

439,958

Income Tax Expense

127,526

130,023

14,530

25,700

40,230

42,815

83,045

46,624

129,668

36,354

33,538

69,892

40,966

110,858

49,187

160,046

Interest

Expense1

46,537

37,271

7,218

8,491

15,709

8,287

23,996

6,806

30,802

7,128

8,838

15,966

7,158

23,124

7,345

30,468

Depreciation

19,980

23,722

5,402

5,248

10,650

5,410

16,059

5,115

21,175

5,608

5,550

11,159

5,720

16,879

5,472

22,352

Amortization

41,226

49,955

10,660

8,629

19,289

8,287

27,577

9,524

37,101

8,387

8,791

17,178

9,046

26,224

7,719

33,943

EBITDA

508,689

574,353

38,557

53,456

92,013

178,643

270,656

195,814

466,470

162,505

150,340

312,846

172,474

485,320

201,446

686,767

Acquisition &

Integration Expenses2

49,554

7,138

Contingent Consideration

12,255

2,541

(366 )

(1,931 )

(2,297 )

(58 )

(2,355 )

(9,873 )

(12,228 )

(7,447 )

(58 )

(7,506 )

(7,429 )

(6,991 )

(14,421 )

FX Hedge Gain

(89,402 )

Gain on sale of divested business

(7,710 )

(4,651 )

(12,361 )

Goodwill Impairment

92,416

Legal Contingency Costs

115,000

Adjusted

EBITDA

481,096

584,032

153,191

143,941

297,132

178,585

475,717

185,941

661,658

147,348

145,631

292,979

172,551

465,530

194,455

659,985

1 Includes write-off of deferred debt origination fees of $3.8M in fiscal 2023

2 Includes lease impairment charge of $16.4M in fiscal 2023

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Nov. 11, 2026

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