Form 8-K

8-K — STERLING INFRASTRUCTURE, INC.

Accession: 0000874238-26-000087

Filed: 2026-06-09

Period: 2026-06-09

CIK: 0000874238

SIC: 1600 (HEAVY CONSTRUCTION OTHER THAN BUILDING CONST - CONTRACTORS)

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — strl-20260609.htm (Primary)

EX-99.1 (a20260609ex991pressrelease.htm)

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8-K — FORM 8-K

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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): June 9, 2026

STERLING INFRASTRUCTURE, INC.

(Exact name of registrant as specified in its charter)

Delaware 001-31993 25-1655321

(State or other jurisdiction of incorporation

or organization) (Commission File Number) (I.R.S. Employer

Identification No.)

1800 Hughes Landing Blvd.

The Woodlands, Texas

77380

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (281) 214-0777

Securities registered pursuant to Section 12(b) of the Act:

Common Stock, $0.01 par value per share STRL The NASDAQ Stock Market LLC

(Title of Class) (Trading Symbol) (Name of each exchange on which registered)

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))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR § 240.12b-2 of this chapter).

Emerging growth company ☐

If 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 7.01 Regulation FD Disclosure.

On June 9, 2026, Sterling Infrastructure, Inc. (the “Company”) issued a press release announcing that it has closed on the acquisition of Stone Ridge Contracting, LLC., a Pocatello, Idaho-based site development contractor. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information set forth in Item 7.01, including Exhibit 99.1, is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section. The information in this Item 7.01, including Exhibit 99.1, shall not be deemed incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit Number Description

99.1

Press release, dated June 9, 2026

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

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

STERLING INFRASTRUCTURE, INC.

Date: June 9, 2026 By: /s/ Mark D. Wolf

Mark D. Wolf

General Counsel and Corporate Secretary

EX-99.1

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Document

NEWS RELEASE

For Immediate Release:

June 9, 2026

Sterling Announces Acquisition of Stone Ridge Contracting, LLC.

THE WOODLANDS, TX – June 9, 2026

Acquisition Expands Sterling's E-Infrastructure Site Development Services Into the Pacific Northwest

Sterling Infrastructure, Inc. (NasdaqGS: STRL) ("Sterling" or "the Company") today announced that it has closed on the acquisition of Stone Ridge Contracting, LLC. (Stone Ridge), a Pocatello, Idaho-based site development contractor. Stone Ridge will join Sterling's E-Infrastructure Solutions segment.

Stone Ridge is a leading, non-union contractor delivering heavy civil, concrete, and construction management services across high-growth sectors including data centers, mining, and industrial infrastructure. The transaction strengthens Sterling's E-Infrastructure geographic footprint across the Pacific Northwest and Texas, which have been key focus areas for strategic geographic expansion. The Stone Ridge service area includes Idaho, Oregon, North Dakota, Washington, and Texas.

Stone Ridge is expected to generate full-year 2026 revenue in the range of $180 million to $200 million and EBITDA margins in the mid-teens, consistent with well-run site development contractors of similar scale. Sterling plans to update its full year 2026 financial guidance to reflect the partial year contribution from Stone Ridge at the time of its second quarter 2026 financial report.

The purchase price multiple paid for Stone Ridge is within Sterling's typical range for site development assets. The upfront purchase price consists of a combination of cash and Sterling common stock. Additionally, Stone Ridge has an earn out opportunity, contingent upon meeting certain EBITDA targets on or before December 31, 2031.

Management Commentary

"We are excited to welcome Stone Ridge to the Sterling family. The team at Stone Ridge has built an exceptional company through a relentless focus on customers, operational excellence, and entrepreneurial leadership," stated Joe Cutillo, Sterling's Chief Executive Officer. “Just as important, they share Sterling’s culture and long-term approach to creating value. We are pleased that the leadership team will remain in place following the transaction to guide the business through its next chapter of growth."

"This acquisition strengthens our ability to serve existing customers across a broader geographic footprint while also adding new, attractive end markets and customer relationships," continued Mr. Cutillo. "Further, we believe that by leveraging Sterling's broad platform and financial resources, there is a compelling opportunity to accelerate growth and drive margin expansion at Stone Ridge. We look forward to building on the strong foundation already in place and capitalizing on the significant opportunities ahead."

About Sterling

Sterling Infrastructure, Inc., (“Sterling,” “the Company,” “we,” “our” or “us”) operates through a variety of subsidiaries within three segments specializing in E-Infrastructure, Transportation and Building Solutions in the United States, primarily across the Southern, Northeastern, Mid-Atlantic and Rocky Mountain regions and the Pacific Islands. E-Infrastructure Solutions provides advanced, large-scale site development services and mission-critical electrical services for data centers, semiconductor fabrication, manufacturing, distribution centers, warehousing, power generation and more. Transportation Solutions includes infrastructure and rehabilitation projects for highways, roads, bridges, airports, ports, rail and storm drainage systems. Building Solutions includes residential and commercial concrete foundations for single-family and multi-family homes, parking structures, elevated slabs, other concrete work, plumbing services, and surveys for new single-family residential builds. From strategy to operations, we are committed to sustainability by operating responsibly to safeguard and improve society’s quality of life. Caring for our people and our communities, our customers and our investors – that is The Sterling Way.

Joe Cutillo, CEO, "We build and service the infrastructure that enables our economy to run,

our people to move and our country to grow."

Company Contact:

Sterling Infrastructure, Inc.

Noelle Dilts, VP of Investor Relations and Corporate Strategy

281-214-0795

Noelle.Dilts@strlco.com

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