STRL / Sterling Infrastructure, Inc. - Pengajuan SECLaporan Tahunan, Pernyataan Proksi

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): September 1, 2025 STERLING INFRAS

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): September 1, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

Sterling Infrastructure Completes Acquisition of CEC Facilities Group Acquisition Expands Suite of E-Infrastructure Services into Mission-Critical Electrical Contracting

NEWS RELEASE For Immediate Release: September 2, 2025 Sterling Infrastructure Completes Acquisition of CEC Facilities Group Acquisition Expands Suite of E-Infrastructure Services into Mission-Critical Electrical Contracting THE WOODLANDS, TX – September 2, 2025 – Sterling Infrastructure, Inc.

Executive Employment Offer dated June 4, 2025 between Sterling Infrastructure, Inc. and Nicholas Grindstaff.

exhibit102-offerletterni

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 ☐ TRANSITION REPORT PURSUANT TO S

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUCTURE,

Q2 2025 EARNINGS CALL August 5, 2025 2Sterling | STRL: Second Quarter 2025 DISCLOSURE: Forward-Looking Statements This presentation contains, and the officers and directors of the Company may from time to time make, statements that are considered for

q22025earningsreleaseppp Q2 2025 EARNINGS CALL August 5, 2025 2Sterling | STRL: Second Quarter 2025 DISCLOSURE: Forward-Looking Statements This presentation contains, and the officers and directors of the Company may from time to time make, statements that are considered forward- looking statements within the meaning of the Securities Act of 1933 and the Securities Exchange Act of 1934.

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): August 4, 2025 STERLING INFRASTRU

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): August 4, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or orga

Sterling Reports Record Second Quarter 2025 Results and Increases Full Year Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: August 4, 2025 Sterling Reports Record Second Quarter 2025 Results and Increases Full Year Guidance THE WOODLANDS, TX – August 4, 2025 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced record financial results for the second quarter of 2025. The financial comparisons herein are to the prior year quarter,

Sterling Announces Appointment of B. Andrew Rose and David Schulz to its Board of Directors

NEWS RELEASE For Immediate Release: July 10, 2025 Sterling Announces Appointment of B.

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

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): July 9, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organi

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 16, 2025 STERLING INFRASTRUC

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 16, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organ

Asset Purchase Agreement, dated as of June 16, 2025, by and among CEC Facilities, LLC, Sterling Infrastructure, Inc., CEC Facilities Group, LLC, MCEC, LLC, CEC Electrical, Inc., Brad Smith, in his capacity as a member of CEC Facilities Group, Daniel Williams, in his capacity as a member of CEC Facilities Group, LLC and as the sellers’ representative, and Ray Waddell, in his capacity as beneficial owner

EX-2.1 Exhibit 2.1 Execution Version ASSET PURCHASE AGREEMENT by and among CEC FACILITIES, LLC, STERLING INFRASTRUCTURE, INC., CEC FACILITIES GROUP, LLC, MCEC, LLC, THE PERSONS IDENTIFIED AS “MEMBERS” ON THE SIGNATURE PAGES HERETO, THE PERSONS IDENTIFIED AS “BENEFICIAL OWNERS” ON THE SIGNATURE PAGES HERETO, and DANIEL WILLIAMS, AS THE SELLERS’ REPRESENTATIVE Dated as of June 16, 2025 TABLE OF CONT

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 16, 2025 STERLING INFRASTRUC

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 16, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organ

Sterling Announces Agreement to Acquire CEC Facilities Group Acquisition Expands Suite of E-Infrastructure Services into Mission-Critical Electrical Contracting Conference Call with Accompanying Slide Deck: June 17, 2025 at 11:00 AM ET/ 10:00 AM CT

EX-99.1 Exhibit 99.1 NEWS RELEASE For Immediate Release: June 17, 2025 Sterling Announces Agreement to Acquire CEC Facilities Group Acquisition Expands Suite of E-Infrastructure Services into Mission-Critical Electrical Contracting Conference Call with Accompanying Slide Deck: June 17, 2025 at 11:00 AM ET/ 10:00 AM CT THE WOODLANDS, TX – June 17, 2025 – Sterling Infrastructure, Inc. (NasdaqGS: STR

Cautionary Statement Regarding Forward-Looking Statements Sterling Infrastructure, Inc. | STRL: CEC Acquisition This presentation contains, and the officers and directors of the Company may from time to time make, statements that are considered forwa

EX-99.2 STERLING TO ACQUIRE CEC FACILITIES GROUP INVESTOR UPDATE June 17, 2025 Exhibit 99.2 Cautionary Statement Regarding Forward-Looking Statements Sterling Infrastructure, Inc. | STRL: CEC Acquisition This presentation contains, and the officers and directors of the Company may from time to time make, statements that are considered forward-looking statements within the meaning of the federal se

Sterling Announces Appointment of Nicholas Grindstaff as Chief Financial Officer

NEWS RELEASE For Immediate Release: June 12, 2025 Sterling Announces Appointment of Nicholas Grindstaff as Chief Financial Officer THE WOODLANDS, TX – June 12, 2025 – Sterling Infrastructure, Inc.

Regulation FD Disclosure, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

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 10, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organ

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 5, 2025 STERLING INFRASTRUCT

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 5, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organi

Sterling Announces Extension and Expansion of Credit Facility

NEWS RELEASE For Immediate Release: June 9, 2025 Sterling Announces Extension and Expansion of Credit Facility THE WOODLANDS, TX – June 9, 2025 – Sterling Infrastructure, Inc.

Amended and Restated Credit Agreement, dated June 5, 2025, by and among Sterling Infrastructure, Inc., the subsidiaries of the Company party thereto as Guarantors, the Lenders party thereto and BMO Bank, N.A. as Administrative Agent

exhibit101-amendedandres Exhibit 10.1 Execution Version AMENDED AND RESTATED CREDIT AGREEMENT dated as of June 5, 2025, among STERLING INFRASTRUCTURE, INC., the Guarantors from time to time parties hereto, the Lenders from time to time parties hereto, and BMO BANK N.A., as Administrative Agent BANK OF AMERICA, N.A. as Syndication Agent BMO CAPITAL MARKETS CORP. and BOFA SECURITIES, INC., as Joint

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): May 8, 2025 STERLING INFRASTRUCTU

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): May 8, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organiz

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2025 ☐ TRANSITION REPORT PURSUANT TO

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2025 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUCTURE

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): May 5, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organiz

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q1 2025 EARNINGS CALL May 6, 2025 2Sterling | STRL: First Quarter 2025 DISCLOSURE: Forward-Looking Statements This presentation cont

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

Sterling Reports First Quarter 2025 Results and Increases Full Year Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: May 5, 2025 Sterling Reports First Quarter 2025 Results and Increases Full Year Guidance THE WOODLANDS, TX – May 5, 2025 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the first quarter of 2025. The financial comparisons herein are to the prior year quarter, unless otherwise noted

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. __) Filed by the Registrant ☑ Filed by a Party other than the Registr

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☑ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☑ Defin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. __) Filed by the Registrant ☑ Filed by a Party other than the Registr

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☑ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Defin

Building Tomorrow Today THE STERLING WAY —— 2025 SUSTAINABILITY REPORT Texas Sterling Construction (TSC) (Transportation Solutions) was a contractor at this project site. The Sterling Way — 2025 Sustainability Report 2 INTRODUCTION 04 About Sterling

a2025sustainabilityrepor Building Tomorrow Today THE STERLING WAY —— 2025 SUSTAINABILITY REPORT Texas Sterling Construction (TSC) (Transportation Solutions) was a contractor at this project site.

Regulation FD Disclosure, Financial Statements and Exhibits

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): March 20, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or orga

Sterling Publishes Its 2025 Sustainability Report

NEWS RELEASE For Immediate Release: March 20, 2025 Sterling Publishes Its 2025 Sustainability Report THE WOODLANDS, TX – March 20, 2025 – Sterling Infrastructure, Inc.

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Investor Presentation Spring 2025 2 DISCLOSURE: Forward-Looking Statements This presentation contains, and the officers and director

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

Regulation FD Disclosure, Financial Statements and Exhibits

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): March 18, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or orga

Sterling Announces the Appointment of Ronald Ballschmiede as Interim Chief Financial Officer and the Departure of Sharon Villaverde as Chief Financial Officer

NEWS RELEASE For Immediate Release: March 14, 2025 Sterling Announces the Appointment of Ronald Ballschmiede as Interim Chief Financial Officer and the Departure of Sharon Villaverde as Chief Financial Officer THE WOODLANDS, TX – March 14, 2025 – Sterling Infrastructure, Inc.

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits, Other Events

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): March 14, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or orga

, 2024 between Sterling Infrastructure, Inc. and

Executive Employment Offer dated

Insider Trading Policy.

strlinsidertradingpolicy Insider Trading Policy For purposes of this Policy, the term "Company" includes all legal entities, subsidiaries or affiliates of Sterling Infrastructure, Inc.

Subsidiaries of the registrant.

Exhibit 21.1 Subsidiaries of the registrant Name State of Incorporation or Organization Texas Sterling Construction Co. Delaware Texas Sterling – Banicki, JV LLC Texas Road and Highway Builders, LLC Nevada Road and Highway Builders Inc. Nevada Road and Highway Builders of California, Inc. California Sterling Hawaii Asphalt, LLC Hawaii Ralph L. Wadsworth Construction Company, LLC Utah J. Banicki Co

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 OR ☐ TRANSITION REPORT PURSUANT TO SE

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUCTURE, INC

Sterling Reports Record Fourth Quarter and Full Year 2024 Results Provides Full Year 2025 Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: February 25, 2025 Sterling Reports Record Fourth Quarter and Full Year 2024 Results Provides Full Year 2025 Guidance THE WOODLANDS, TX – February 25, 2025 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the fourth quarter and full year 2024 and provided full year 2025 guidance. The

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): February 25, 2025 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q4 2024 Earnings Call February 26, 2025 2Sterling | STRL: Fourth Quarter 2024 DISCLOSURE: Forward-Looking Statements This presentati

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

Financial Statements and Exhibits, Other Events

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): December 31, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

Sterling Announces Amendment to Road and Highway Builders, LLC Operating Agreement

Exhibit 99.1 NEWS RELEASE For Immediate Release: January 7, 2025 Sterling Announces Amendment to Road and Highway Builders, LLC Operating Agreement THE WOODLANDS, TX – January 7, 2025 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) ("Sterling" or "the Company") today announced that it executed an amendment to its Road and Highway Builders, LLC (“RHB”) Operating agreement on December 31, 2024. Thi

Other Events

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): December 10, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

Regulation FD Disclosure, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

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 14, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

Sterling Announces the Retirement of Thomas M. White from the Board of Directors

Exhibit 99.1 NEWS RELEASE For Immediate Release: November 15, 2024 Sterling Announces the Retirement of Thomas M. White from the Board of Directors THE WOODLANDS, TX – November 15, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) ("Sterling" or "the Company") today announced that Thomas M. White will retire from the company’s Board of Directors (the “Board”) effective December 31, 2024. Mr. W

Amended and Restated Bylaws of Sterling Infrastructure, Inc. (incorporated by reference to Exhibit 3.2 to Sterling Infrastructure, Inc.’s Quarterly Report on Form 10-Q, filed on November 7, 2024 (SEC file No. 1-31993)).

Page 1 of 21 #102763740v1 STERLING INFRASTRUCTURE, INC. (the “Corporation”) AMENDED AND RESTATED BYLAWS (as amended on November 4, 2024) ARTICLE I OFFICES Section 1.1 Registered Office. The registered office of the Corporation in the State of Delaware shall be set forth in the Certificate of Incorporation of the Corporation. Section 1.2 Principal and Other Offices. The Corporation may also have a

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2024 ☐ TRANSITION REPORT PURSUANT

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2024 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUC

Sterling Reports Record Third Quarter 2024 Results and Raises Full Year Profitability Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: November 6, 2024 Sterling Reports Record Third Quarter 2024 Results and Raises Full Year Profitability Guidance THE WOODLANDS, TX – November 6, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the third quarter 2024. The financial comparisons herein are to the prior year quarte

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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 6, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or or

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q3 2024 Earnings Call November 7, 2024 2Sterling | STRL: Third Quarter 2024 DISCLOSURE: Forward-Looking Statements This presentation

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. D. A. Davidson's 23rd Annual Diversified Industrials & Services Conference September 19, 2024 2 DISCLOSURE: Forward-Looking Statemen

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

Regulation FD Disclosure, Financial Statements and Exhibits

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): September 18, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or

Regulation FD Disclosure, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

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): August 26, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or org

Sterling Announces the Retirement of Charles R. Patton from the Board of Directors

Exhibit 99.1 NEWS RELEASE For Immediate Release: August 28, 2024 Sterling Announces the Retirement of Charles R. Patton from the Board of Directors THE WOODLANDS, TX – August 28, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) ("Sterling" or "the Company") today announced that Charles R. Patton will retire from the company’s Board of Directors (the “Board”) effective September 1, 2024. Mr. P

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): August 3, 2024 STERLING INFRASTRU

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): August 3, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or orga

Sterling Announces Appointment of Dan Govin as Chief Operating Officer

Exhibit 99.1 NEWS RELEASE For Immediate Release: August 8, 2024 Sterling Announces Appointment of Dan Govin as Chief Operating Officer THE WOODLANDS, TX – August 8, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) ("Sterling" or "the Company") today announced the appointment of Dan Govin as Chief Operating Officer (“COO”). In this role, Dan will be responsible for leading the execution of Ste

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2024 ☐ TRANSITION REPORT PURSUANT TO S

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2024 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUCTURE,

Sterling Reports Record Second Quarter 2024 Results and Raises Full Year Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: August 5, 2024 Sterling Reports Record Second Quarter 2024 Results and Raises Full Year Guidance THE WOODLANDS, TX – August 5, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the second quarter 2024. The financial comparisons herein are to the prior year quarter, unless otherw

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): August 5, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or orga

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q2 2024 Earnings Call August 6, 2024 2Sterling | STRL: Second Quarter 2024 DISCLOSURE: Forward-Looking Statements This presentation

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Investor Presentation Summer 2024 2 DISCLOSURE: Forward-Looking Statements This presentation contains, and the officers and director

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

Regulation FD Disclosure, Financial Statements and Exhibits

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 3, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organi

Sterling Announces Planned 2024 Executive Transitions - Sharon Villaverde Appointed Chief Financial Officer and Chief Accounting Officer

Exhibit 99.1 NEWS RELEASE For Immediate Release: May 15, 2024 Sterling Announces Planned 2024 Executive Transitions - Sharon Villaverde Appointed Chief Financial Officer and Chief Accounting Officer THE WOODLANDS, TX – May 15, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) ("Sterling" or "the Company") today announced the promotion of Sharon Villaverde to the roles of Chief Financial Office

Regulation FD Disclosure, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

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): May 11, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organi

Sterling Infrastructure, Inc. Second Amended and Restated 2018 Stock Incentive Plan.

EXHIBIT 99.1 STERLING INFRASTRUCTURE, INC. SECOND AMENDED AND RESTATED 2018 STOCK INCENTIVE PLAN 1. Purpose. The purpose of the Second Amended and Restated 2018 Stock Incentive Plan (the “Plan”) is to increase stockholder value and advance the interests of the Company and its Subsidiaries by furnishing a variety of equity incentives designed to (a) attract, retain, and motivate key employees, offi

Filing Fee Table

EXHIBIT 107 Calculation of Filing Fee Table Form S-8 (Form Type) Sterling Infrastructure, Inc.

As filed with the Securities and Exchange Commission on May 9, 2024. Registration No. 333-_________

As filed with the Securities and Exchange Commission on May 9, 2024. Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 25-1655321 (State or other jurisdiction of incorporation or organization) (I.R

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

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): May 9, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organiz

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2024 ☐ TRANSITION REPORT PURSUANT TO

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2024 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUCTURE

Sterling Reports Record First Quarter 2024 Results

Exhibit 99.1 NEWS RELEASE For Immediate Release: May 6, 2024 Sterling Reports Record First Quarter 2024 Results THE WOODLANDS, TX – May 6, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the first quarter 2024. The financial comparisons herein are to the prior year quarter, unless otherwise noted. First Quarter 2024 Results

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): May 6, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organiz

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q1 2024 Earnings Call May 7, 2024 2Sterling | STRL: First Quarter 2024 DISCLOSURE: Forward-Looking Statements This presentation cont

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. __) Filed by the Registrant ☑ Filed by a Party other than the Registr

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☑ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☑ Defin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. __) Filed by the Registrant ☑ Filed by a Party other than the Registr

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☑ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Defin

Sterling Publishes Its 2024 Sustainability Report

Exhibit 99.1 NEWS RELEASE For Immediate Release: March 19, 2024 Sterling Publishes Its 2024 Sustainability Report THE WOODLANDS, TX – March 19, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) ("Sterling" or "the Company") has published its 2024 Sustainability Report titled, For Better and Beyond – The Sterling Way. The report highlights Sterling’s ongoing sustainability efforts woven into co

Regulation FD Disclosure, Financial Statements and Exhibits

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): March 19, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or orga

For Better and Beyond THE STERLING WAY —— 2024 SUSTAINABILITY REPORT The Sterling Way — 2024 Sustainability Report 2 INTRODUCTION 04 About Sterling 05 Awards and Industry Recognition 07 Messages from Our Leaders 12 The Sterling Way 13 Deepening Our C

For Better and Beyond THE STERLING WAY —— 2024 SUSTAINABILITY REPORT The Sterling Way — 2024 Sustainability Report 2 INTRODUCTION 04 About Sterling 05 Awards and Industry Recognition 07 Messages from Our Leaders 12 The Sterling Way 13 Deepening Our Commitment 14 Forging a Sustainable Future CORPORATE GOVERNANCE 16 A Foundation of Integrity and Transparency 17 Ethics and Compliance 18 Risk Management 19 Protecting Data.

Sterling Infrastructure, Inc. Clawback Policy, effective as of October 2, 2023.

Policy for the Recovery of Erroneously Awarded Compensation A. Overview In accordance with Listing Rule 5608 of The Nasdaq Stock Market (the “Nasdaq Rules”), Section 10D and Rule 10D-1 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) (“Rule 10D- 1”), the Board of Directors (the “Board”) of Sterling Infrastructure, Inc. (the “Company”) has adopted this Policy (the “Policy”) t

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SE

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUCTURE, INC

Subsidiaries of the registrant.

Exhibit 21.1 Subsidiaries of the registrant Name State of Incorporation or Organization Texas Sterling Construction Co. Delaware Texas Sterling – Banicki, JV LLC Texas Road and Highway Builders, LLC Nevada Road and Highway Builders Inc. Nevada Road and Highway Builders of California, Inc. California Sterling Hawaii Asphalt, LLC Hawaii Ralph L. Wadsworth Construction Company, LLC Utah Ralph L. Wads

Amended and Restated Executive Employment Agreement dated January 1, 2024 between Sterling Infrastructure, Inc. and Joseph A. Cutillo (incorporated by reference to Exhibit 10.4 to Sterling Infrastructure, Inc.'s Annual Report on Form 10-K filed on February 27, 2024 (SEC File No. 1-31993)).

maimer. If you do not accept the tenns of this Agreement. the PS Us are subject to cancellation. IN WITNESS WHEREOF, the parties have signed this Agreement as of the Grant Date, but recognize that the effectiveness of the Agreement and the Awards are contingent on the approval of the Plan by the Company’s stockholders and on the Company’s filing a Form S-8 registration statement with the Securitie

Standard Non-Employee Director Compensation adopted by the Board of Directors effective May 3, 2023.

Exhibit 10.3.1 Standard Non-Employee Director Compensation (Adopted by the Board of Directors Effective May 3, 2023) Annual Fees-Each Non-Employee Director ● $100,000 cash (paid in monthly installments) ● An award on the date of each Annual Meeting of Stockholders of shares of restricted common stock valued at $135,000.(1) Annual Fees: — Board and Committee Chairs (paid in monthly installments) ●

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q4 2023 Earnings Call February 27, 2024 2Sterling | STRL: Fourth Quarter 2023 DISCLOSURE: Forward-Looking Statements This presentati

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): February 26, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

Sterling Reports Record Fourth Quarter and Full Year 2023 Results Provides 2024 Full Year Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: February 26, 2024 Sterling Reports Record Fourth Quarter and Full Year 2023 Results Provides 2024 Full Year Guidance THE WOODLANDS, TX – February 26, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the fourth quarter and full year 2023 and provided full year 2024 guidance. The

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

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): February 21, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

NEWS RELEASE For Immediate Release: February 22, 2024 Sterling Announces Election of William Bosway to its Board of Directors THE WOODLANDS, TX – February 22, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or “the Company”) today a

NEWS RELEASE For Immediate Release: February 22, 2024 Sterling Announces Election of William Bosway to its Board of Directors THE WOODLANDS, TX – February 22, 2024 – Sterling Infrastructure, Inc.

STRL / Sterling Infrastructure, Inc. / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SC 13G/A 1 tv01998-sterlinginfrastructu.htm SCHEDULE 13G/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 2)* Name of issuer: Sterling Infrastructure Inc Title of Class of Securities: Common Stock CUSIP Number: 859241101 Date of Event Which Requires Filing of this Statement: December 29, 2023 Check the appropriate bo

Regulation FD Disclosure, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

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): February 12, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

NEWS RELEASE For Immediate Release: February 12, 2024 Sterling Announces Planned Retirement of Chief Financial Officer Ronald Ballschmiede THE WOODLANDS, TX – February 12, 2024 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or “the Comp

NEWS RELEASE For Immediate Release: February 12, 2024 Sterling Announces Planned Retirement of Chief Financial Officer Ronald Ballschmiede THE WOODLANDS, TX – February 12, 2024 – Sterling Infrastructure, Inc.

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): January 5, 2024 STERLING INFRASTR

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): January 5, 2024 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or org

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): December 27, 2023 STERLING INFRAS

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): December 27, 2023 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

Fifth Amendment to Credit Agreement, dated December 27, 2023, by and among Sterling Infrastructure, Inc., the subsidiaries of the Company party thereto as Guarantors, the Lenders party thereto and BMO Bank, N.A., as Administrative Agent (incorporated by reference to Exhibit 10.1 to Sterling Infrastructure, Inc.’s Current Report on Form 8-K, filed on December 28, 2023 (SEC File No. 1-31993)).

exhibit101-fifthamendmen Execution Version 759613533.8 FIFTH AMENDMENT TO CREDIT AGREEMENT THIS FIFTH AMENDMENT TO CREDIT AGREEMENT (this “Amendment”), dated as of December 27, 2023, is entered into by and among STERLING INFRASTRUCTURE, INC. (F/K/A STERLING CONSTRUCTION COMPANY, INC.), a Delaware corporation (the “Borrower”), the Guarantors party hereto, the Lenders party hereto and BMO BANK N.A.,

NEWS RELEASE For Immediate Release: December 28, 2023 Sterling Announces Extension of Credit Facility THE WOODLANDS, TX – December 28, 2023 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or “the Company”) today announced that it request

exhibit991-pressreleasex NEWS RELEASE For Immediate Release: December 28, 2023 Sterling Announces Extension of Credit Facility THE WOODLANDS, TX – December 28, 2023 – Sterling Infrastructure, Inc.

Sterling Announces Authorization of a $200 Million Stock Repurchase Program

Exhibit 99.1 NEWS RELEASE For Immediate Release: December 5, 2023 Sterling Announces Authorization of a $200 Million Stock Repurchase Program THE WOODLANDS, TX – December 5, 2023 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or “the Company”) today announced that its Board of Directors has authorized a program to repurchase shares of Sterling’s outstanding common stock. Under the pr

Financial Statements and Exhibits, Other Events

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): December 5, 2023 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or or

Sterling Acquires Texas-Based Professional Plumbers Group

Exhibit 99.1 NEWS RELEASE For Immediate Release: November 16, 2023 Sterling Acquires Texas-Based Professional Plumbers Group THE WOODLANDS, TX – November 16, 2023 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or “the Company”) today announced that it has acquired Professional Plumbers Group, Incorporated (PPG), headquartered in Wylie, Texas. PPG serves a range of residential home bu

Regulation FD Disclosure, Financial Statements and Exhibits

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 16, 2023 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2023 ☐ TRANSITION REPORT PURSUANT

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2023 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUC

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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 6, 2023 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or or

Sterling Reports Third Quarter 2023 Results and Increases 2023 Full Year Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: November 6, 2023 Sterling Reports Third Quarter 2023 Results and Increases 2023 Full Year Guidance THE WOODLANDS, TX – November 6, 2023 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the third quarter 2023. The financial information herein is from continuing operations and compari

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q3 2023 Earnings Call November 7, 2023 2Sterling | STRL: Third Quarter 2023 DISCLOSURE: Forward-Looking Statements This presentation

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

As filed with the Securities and Exchange Commission on October 10, 2023

As filed with the Securities and Exchange Commission on October 10, 2023 Registration No.

Description of Securities Registered Under Section 12 (incorporated by reference to Exhibit 4.2 to Sterling Infrastructure, Inc.’s Form 10-Q filed on August 8, 2023 (SEC File No. 1-31993)).

#101202926v3 Exhibit 4.2 DESCRIPTION OF SECURITIES REGISTERED UNDER SECTION 12 OF THE EXCHANGE ACT OF 1934 The following summary of the terms of the capital stock of Sterling Infrastructure, Inc. (“Sterling,” “we,” “us,” or “our”) is not meant to be complete and is qualified by reference to the relevant provisions of the General Corporation Law of the State of Delaware (the “DGCL”) and the complet

Fourth Amendment to Credit Agreement, dated June 5, 2023, by and among Sterling Infrastructure, Inc, the subsidiaries of the Company party thereto as Guarantors, the Lenders party thereto and BMO Harris Bank N.A., as Administrative Agent (incorporated by reference to Exhibit 10.1 to Sterling Infrastructure, Inc.’s Quarterly Report on Form 10-Q, filed on August 8, 2023 (SEC File No. 1-31993)).

ex101-fourthamendmenttoc EXECUTION VERSION 751971197.3 FOURTH AMENDMENT TO CREDIT AGREEMENT THIS FOURTH AMENDMENT TO CREDIT AGREEMENT (this “Amendment”), dated as of June 5, 2023, is entered into by and among STERLING INFRASTRUCTURE, INC. (F/K/A STERLING CONSTRUCTION COMPANY, INC.), a Delaware corporation (the “Borrower”), the Guarantors party hereto, the Lenders party hereto and BMO HARRIS BANK N

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2023 ☐ TRANSITION REPORT PURSUANT TO S

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2023 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUCTURE,

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q2 2023 Earnings Call August 8, 2023 2Sterling | STRL: Second Quarter 2023 DISCLOSURE: Forward-Looking Statements This presentation

q22023earningsreleasepre We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

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): August 7, 2023 STERLING INFRASTRU

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): August 7, 2023 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or orga

Sterling Reports Second Quarter 2023 Record Results Increases 2023 Full Year Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: August 7, 2023 Sterling Reports Second Quarter 2023 Record Results Increases 2023 Full Year Guidance THE WOODLANDS, TX – August 7, 2023 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the second quarter 2023. The financial information herein is from continuing operations and compar

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): May 31, 2023 STERLING INFRASTRUCT

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): May 31, 2023 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organi

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. INVESTOR PRESENTATION MAY 2023 DISCLOSURE: Forward-Looking Statements This presentation contains, and the officers and directors of

strlirpresentationx0530 We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

Form of Common Stock Certificate of Sterling Infrastructure, Inc. (incorporated by reference to Exhibit 4.1 to Sterling Infrastructure, Inc.'s Registration Statement on Form 8-A, filed on May 12, 2023 (SEC File No. 1-31993)).

ex41-formofcommonstockce NUMBER SHARES COUNTERSIGNED: BROADRIDGE CORPORATE ISSUER SOLUTIONS, INC.

Composite Certificate of Incorporation of Sterling Infrastructure, Inc. as amended through May 3, 2023 (incorporated by reference to Exhibit 3.1 to Sterling Infrastructure, Inc.’s Registration Statement on Form 8-A, filed on May 12, 2023 (SEC File No. 1-31993)).

ex31-strlxcompositecerti Exhibit 3.1 COMPOSITE CERTIFICATE OF INCORPORATION OF STERLING INFRASTRUCTURE, INC. Article I The name of the Corporation is Sterling Infrastructure, Inc. (hereinafter sometimes referred to as the "Corporation.") Article II The name of the registered agent for service of process of the Corporation is The Corporation Trust Company with an address at 1209 Orange Street, Wilm

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-A/A (Amendment No. 1) FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES PURSUANT TO SECTION 12(b) or (g) OF THE SECURITIES EXCHANGE ACT OF 1934 STERLING INFRASTRUCTURE, IN

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-A/A (Amendment No. 1) FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES PURSUANT TO SECTION 12(b) or (g) OF THE SECURITIES EXCHANGE ACT OF 1934 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 25-1655321 (State or other jurisdiction of incorporation or organization) (I.R.S. E

Certificate of Amendment to the Restated Certificate of Incorporation of Sterling Infrastructure, Inc.

Exhibit 3.1 CERTIFICATE OF AMENDMENT OF CERTIFICATE OF INCORPORATION OF STERLING INFRASTRUCTURE, INC. Sterling Infrastructure, Inc. (the “Corporation”), a corporation organized and existing under the General Corporation Law of the State of Delaware, hereby certifies as follows: 1.This Certificate of Amendment (the “Certificate of Amendment”) amends the provisions of the Corporation’s Restated Cert

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): May 3, 2023 STERLING INFRASTRUCTU

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): May 3, 2023 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organiz

Fee Table

exhibit107feetable Exhibit 107 #100964286v2 Calculation of Filing Fee Tables Form S-3 (Form Type) Sterling Infrastructure, Inc.

As filed with the Securities and Exchange Commission on May 2, 2023

As filed with the Securities and Exchange Commission on May 2, 2023 Registration No.

Form of Indenture (including form of senior debt security).

ex43-sterlinginfrastruct #101193523v4 Exhibit 4.3 STERLING INFRASTRUCTURE, INC. AND U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION Trustee INDENTURE DATED AS OF , 20 SENIOR DEBT SECURITIES #101193523v4 STERLING INFRASTRUCTURE, INC. RECONCILIATION AND TIE BETWEEN TRUST INDENTURE ACT OF 1939, AS AMENDED, AND INDENTURE, DATED AS OF , 20 TRUST INDENTURE ACT SECTION INDENTURE SECTION Section 310(a)(1) 6

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2023 ☐ TRANSITION REPORT PURSUANT TO

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2023 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUCTURE

Statement of Eligibility and Qualification on Form T-1 of U.S. Bank Trust Company, National Association, as trustee under Form of Indenture.

ex251-formtx1 #101209185v1 Exhibit 25.1 SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE Check if an Application to Determine Eligibility of a Trustee Pursuant to Section 305(b)(2) U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION (Exact name of Trustee as specified in its cha

Sterling Reports Record First Quarter 2023 Results

Exhibit 99.1 NEWS RELEASE For Immediate Release: May 1, 2023 Sterling Reports Record First Quarter 2023 Results THE WOODLANDS, TX – May 1, 2023 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the first quarter 2023. The financial information herein is from continuing operations and comparisons are to the prior year quarter, unles

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q1 2023 Earnings Call May 2, 2023 2Sterling | STRL: First Quarter 2023 DISCLOSURE: Forward-Looking Statements This presentation cont

q12023earningsreleaseppp We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): May 1, 2023 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or organiz

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): April 24, 2023 STERLING INFRASTRU

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): April 24, 2023 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or orga

LEADING THE WAY THE STERLING WAY —— 2023 SUSTAINABILITY REPORT THE STERLING WAY — 2023 SUSTAINABILITY REPORT 2 INTRODUCTION About Sterling 3 A Message from Our Leaders 4 Championing the Cause 7 The Sterling Way 8 Laying the Groundwork 9 GOVERNANCE So

sterling2023sustainabili LEADING THE WAY THE STERLING WAY —— 2023 SUSTAINABILITY REPORT THE STERLING WAY — 2023 SUSTAINABILITY REPORT 2 INTRODUCTION About Sterling 3 A Message from Our Leaders 4 Championing the Cause 7 The Sterling Way 8 Laying the Groundwork 9 GOVERNANCE Sound and Effective Governance 12 Ethics and Compliance 14 Risk Management 15 Protecting Data 16 SAFETY Protecting Our People 1

Sterling Publishes Its 2023 Sustainability Report

NEWS RELEASE For Immediate Release: April 24, 2023 Sterling Publishes Its 2023 Sustainability Report THE WOODLANDS, TX – April 24, 2023 – Sterling Infrastructure, Inc.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. 1) Filed by the Registrant ☑ Filed by a Party other than the Registra

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. 1) Filed by the Registrant ☑ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Defi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. __) Filed by the Registrant ☑ Filed by a Party other than the Registr

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☑ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☑ Defin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. __) Filed by the Registrant ☑ Filed by a Party other than the Registr

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☑ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Defin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. __) Filed by the Registrant ☑ Filed by a Party other than the Registr

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☑ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☑ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Defin

Sterling Reports Record Fourth Quarter and Full Year 2022 Results Provides 2023 Full Year Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: February 27, 2023 Sterling Reports Record Fourth Quarter and Full Year 2022 Results Provides 2023 Full Year Guidance THE WOODLANDS, TX – February 27, 2023 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the fourth quarter and full year 2022 and provided full year 2023 guidance. Fou

Standard Non-Employee Director Compensation adopted by the Board of Directors effective May 5, 2021.

Exhibit 10.3.1 Standard Non-Employee Director Compensation (Adopted by the Board of Directors Effective May 5, 2021) Annual Fees-Each Non-Employee Director ● $90,000 cash (paid in monthly installments) ● An award on the date of each Annual Meeting of Stockholders of shares of restricted common stock valued at $100,000.(1) Annual Fees: — Board and Committee Chairs (paid in monthly installments) ● C

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q4 2022 Earnings Call February 28, 2023 2Sterling | STRL: Fourth Quarter 2022 DISCLOSURE: Forward-Looking Statements This presentati

q42022earningsreleaseppp We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

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): February 27, 2023 STERLING INFRAS

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): February 27, 2023 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 ☐ TRANSITION REPORT PURSUANT TO SECTI

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUCTURE, INC

Subsidiaries of the registrant.

Exhibit 21.1 Subsidiaries of the registrant Name State of Incorporation or Organization Texas Sterling Construction Co. Delaware Texas Sterling – Banicki, JV LLC Texas Road and Highway Builders, LLC Nevada Road and Highway Builders Inc. Nevada Road and Highway Builders of California, Inc. California Sterling Hawaii Asphalt, LLC Hawaii Ralph L. Wadsworth Construction Company, LLC Utah Ralph L. Wads

STRL / Sterling Construction Company, Inc. / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 1)* Name of issuer: Sterling Infrastructure Inc. Title of Class of Securities: Common Stock CUSIP Number: 859241101 Date of Event Which Requires Filing of this Statement: December 30, 2022 Check the appropriate box to designate the rule pursuant to which this Schedule is

Sterling Acquires a Concrete Foundations Business in Arizona

EX-99.1 2 a20221220ex991pressrelease.htm EX-99.1 Exhibit 99.1 NEWS RELEASE For Immediate Release: December 20, 2022 Sterling Acquires a Concrete Foundations Business in Arizona THE WOODLANDS, TX – December 20, 2022 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or “the Company”) today announced that it has acquired Concrete Construction Services of Arizona L.L.C. and its affiliated c

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): December 20, 2022 STERLING INFRAS

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): December 20, 2022 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

Sterling Announces Strategic Divestiture of its 50% Stake in Myers & Sons Construction

EX-99.1 2 a20221201ex991pressrelease.htm EX-99.1 Exhibit 99.1 NEWS RELEASE For Immediate Release: December 1, 2022 Sterling Announces Strategic Divestiture of its 50% Stake in Myers & Sons Construction THE WOODLANDS, TX – On November 30, 2022, Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) entered into an agreement (the “Agreement”) and sold the Company’s 50% ownershi

Financial Statements and Exhibits, Other Events

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 30, 2022 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

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): October 31, 2022 STERLING INFRAST

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): October 31, 2022 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or or

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q3 2022 Earnings Call November 1, 2022 2Sterling | STRL: Third Quarter 2022 DISCLOSURE: Forward-Looking Statements This presentation

a20221031ex992presentati We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

Sterling Reports Record Third Quarter 2022 Results Results Continue to Outpace Expectations Increases 2022 Full Year Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: October 31, 2022 Sterling Reports Record Third Quarter 2022 Results Results Continue to Outpace Expectations Increases 2022 Full Year Guidance THE WOODLANDS, TX – October 31, 2022 – Sterling Infrastructure, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced financial results for the third quarter 2022. Third Quarter 2022 Results •To

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2022 ☐ TRANSITION REPORT PURSUANT

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2022 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUC

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2022 ☐ TRANSITION REPORT PURSUANT TO S

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2022 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING INFRASTRUCTURE,

Certificate of Incorporation of Sterling Infrastructure, Inc. as amended through June 1, 2022.

Exhibit 3.1 CERTIFICATE OF INCORPORATION OF STERLING INFRASTRUCTURE, INC. Article I The name of the Corporation is Sterling Infrastructure, Inc. (hereinafter sometimes referred to as the "Corporation.") Article II The name of the registered agent for service of process of the Corporation is The Corporation Trust Company with an address at 1209 Orange Street, Wilmington, New Castle County, Delaware

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q2 2022 Earnings Call August 2, 2022 2Sterling: Second Quarter 2022 DISCLOSURE: Forward-Looking Statements This presentation contain

EX-99.2 3 a20220801ex991presentati.htm EX-99.2 We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. Q2 2022 Earnings Call August 2, 2022 2Sterling: Second Quarter 2022 DISCLOSURE: Forward-Looking Statements This presentation contains, and the officers and directors of the Company may from time to time make, statements that are consid

Sterling Reports Record Second Quarter 2022 Results Earnings Continue to Outpace Expectations Increases 2022 Full Year Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: August 1, 2022 Sterling Reports Record Second Quarter 2022 Results Earnings Continue to Outpace Expectations Increases 2022 Full Year Guidance THE WOODLANDS, TX ? August 1, 2022 ? Sterling Infrastructure, Inc. (NasdaqGS: STRL) (?Sterling? or the ?Company?) today announced financial results for the second quarter 2022. Second Quarter 2022 Results ?To

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): August 1, 2022 STERLING INFRASTRUCTURE, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or orga

Amended and Restated Certificate of Incorporation of Sterling Infrastructure, Inc. as amended through June 1, 2022 (incorporated by reference to Exhibit 3.1 to Sterling Infrastructure, Inc.’s Current Report on Form 8-K, filed on June 1, 2022 (SEC File No. 1-31993)).

#86044232v1 Exhibit 3.1 CERTIFICATE OF AMENDMENT OF CERTIFICATE OF INCORPORATION OF STERLING CONSTRUCTION COMPANY, INC. Sterling Construction Company, Inc. (the ?Corporation?), a corporation organized and existing under the General Corporation Law of the State of Delaware, hereby certifies as follows: 1. This Certificate of Amendment (the ?Certificate of Amendment?) amends the provisions of the Co

Amended and Restated Bylaws of Sterling Infrastructure, Inc. (incorporated by reference to Exhibit 3.2 to Sterling Infrastructure, Inc.’s Current Report on Form 8-K, filed on June 1, 2022 (SEC File No. 1-31993)).

a20220601ex32 {N4555381.2} Page 1 of 18 Exhibit 3.2 STERLING INFRASTRUCTURE, INC. (the “Corporation”) AMENDED AND RESTATED BYLAWS (as amended on June 1, 2022) ARTICLE I OFFICES Section 1.1 Principal Office. The principal office of the Corporation is located at 2751 Centerville Road - Suite 3131, Wilmington, Delaware 19803. Section 1.2 Registered Office. The registered office of the Corporation in

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. INVESTOR PRESENTATION Sterling Announces Name Change to Sterling Infrastructure, Inc. June 2022 DISCLOSURE: Forward-Looking Statemen

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

NEWS RELEASE For Immediate Release: May 31, 2022 Sterling Aligns Company Name to Reflect Leadership in Infrastructure Solutions THE WOODLANDS, TX – May 31, 2022 – Sterling Construction Company, Inc. (NasdaqGS: STRL) (“Sterling” or “the company”) anno

NEWS RELEASE For Immediate Release: May 31, 2022 Sterling Aligns Company Name to Reflect Leadership in Infrastructure Solutions THE WOODLANDS, TX ? May 31, 2022 ? Sterling Construction Company, Inc.

Regulation FD Disclosure, Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits, Other Events

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 1, 2022 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or

May 12, 2022 Via EDGAR United States Securities and Exchange Commission Division of Corporation Finance Office of Real Estate & Construction 100 F. Street, N.E. Washington, D.C. 20549 Attention: Ameen Hamady Re: Sterling Construction Company, Inc. Fo

May 12, 2022 Via EDGAR United States Securities and Exchange Commission Division of Corporation Finance Office of Real Estate & Construction 100 F.

Submission of Matters to a Vote of Security Holders

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): May 4, 2022 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2022 ☐ TRANSITION REPORT PURSUANT TO

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2022 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING CONSTRUCTION C

Sterling Reports Record First Quarter 2022 Results Earnings Continue to Outpace Expectations Petillo Delivers Immediately Accretive Earnings

Exhibit 99.1 NEWS RELEASE For Immediate Release: May 2, 2022 Sterling Reports Record First Quarter 2022 Results Earnings Continue to Outpace Expectations Petillo Delivers Immediately Accretive Earnings THE WOODLANDS, TX ? May 2, 2022 ? Sterling Construction Company, Inc. (NasdaqGS: STRL) (?Sterling? or the ?Company?) today announced financial results for the first quarter 2022. First Quarter 2022

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow. 1ST QUARTER EARNINGS CALL May 3, 2022 DISCLOSURE: Forward-Looking Statements This presentation contains, and the officers and direct

We build and service the infrastructure that enables our economy to run, our people to move, and our country to grow.

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): May 2, 2022 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A Amendment No. 1 ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 ☐ TRANSITION REPORT

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A Amendment No. 1 ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING C

Regulation FD Disclosure, Financial Statements and Exhibits

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): March 23, 2022 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation o

Sterling Publishes Its 2022 Sustainability Report

NEWS RELEASE For Immediate Release: March 23, 2022 Sterling Publishes Its 2022 Sustainability Report THE WOODLANDS, TX ? March 23, 2022 ? Sterling Construction Company, Inc.

THE STERLING WAY —— 2022 SUSTAINABILITY REPORT BUILDING A BETTER TOMORROW STRLCO 2022 SUSTAINABILITY (ESG) REPORT | 2 TABLE OF CONTENTS CEO Message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Executive

THE STERLING WAY ?? 2022 SUSTAINABILITY REPORT BUILDING A BETTER TOMORROW STRLCO 2022 SUSTAINABILITY (ESG) REPORT | 2 TABLE OF CONTENTS CEO Message .

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. __) Filed by the Registrant ☑ Filed by a Party other than the Registr

DEF 14A 1 a20220323def14a-definitive.htm DEF 14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☑ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commissio

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. __) Filed by the Registrant ☑ Filed by a Party other than the Registr

DEFA14A 1 a20220323defa14a-proxynoti.htm DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☑ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commissio

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 ☐ TRANSITION REPORT PURSUANT TO SECTI

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING CONSTRUCTION COMPAN

We build and service the infrastructure that enables our economy to run, our people to move and our country to grow. 4TH QUARTER AND FULL YEAR Earnings call March 1, 2022 2S t e r l i n g : F o u r t h Q u a r t e r & F u l l Y e a r 2 0 2 1 This pre

We build and service the infrastructure that enables our economy to run, our people to move and our country to grow.

Subsidiaries of the registrant.

Exhibit 21.1 Subsidiaries of the registrant Name State of Incorporation or Organization Texas Sterling Construction Co. Delaware Texas Sterling ? Banicki, JV LLC Texas Road and Highway Builders, LLC Nevada Road and Highway Builders Inc. Nevada Road and Highway Builders of California, Inc. California Sterling Hawaii Asphalt, LLC Hawaii Ralph L. Wadsworth Construction Company, LLC Utah Ralph L. Wads

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): February 28, 2022 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporatio

Sterling Reports Record Fourth Quarter and Full Year 2021 Results EPS Continues to Outpace Expectations Delivered Record Full Year Operating Cash Flow Provides 2022 Full Year Revenue and Net Income Guidance

EX-99.1 2 a20220228ex991earningsrele.htm EX-99.1 Exhibit 99.1 NEWS RELEASE For Immediate Release: February 28, 2022 Sterling Reports Record Fourth Quarter and Full Year 2021 Results EPS Continues to Outpace Expectations Delivered Record Full Year Operating Cash Flow Provides 2022 Full Year Revenue and Net Income Guidance THE WOODLANDS, TX – February 28, 2022 – Sterling Construction Company, Inc. (

STRL / Sterling Construction Company, Inc. / VANGUARD GROUP INC - SCHEDULE 13G Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 Name of issuer: Sterling Construction Co. Inc. Title of Class of Securities: Common Stock CUSIP Number: 859241101 Date of Event Which Requires Filing of this Statement: December 31, 2021 Check the appropriate box to designate the rule pursuant to which this Schedule is filed: ??Rule 13d

STRL / Sterling Construction Company, Inc. / WELLINGTON MANAGEMENT GROUP LLP - SEC SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2 )* Sterling Construction Company, Inc. (Name of Issuer) Common Stock (Title of Class of Securities) 859241101 (CUSIP Number) December 31, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant

As filed with the Securities and Exchange Commission on January 6, 2022. Registration No. 333-88228

As filed with the Securities and Exchange Commission on January 6, 2022. Registration No. 333-88228 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-8 REGISTRATION STATEMENT NO. 333-88228 UNDER THE SECURITIES ACT OF 1933 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 25-1655321 (Sta

Stock Purchase Agreement, dated as of December 30, 2021, by and among Michael V. Petillo, in his individual capacity and as the sellers’ representative, the 2020 Audrey Petillo Family Trust, the Michael V. Petillo Family Trust, Petillo LLC, Petillo NY LLC, Petillo Maryland Incorporated, Petillo NJ Holdings Incorporated, Petillo NY Holdings Incorporated, Petillo MD Holdings Incorporated and Sterling Construction Company, Inc. (incorporated by reference to Exhibit 2.1 to Sterling Construction Company, Inc.’s Current Report on Form 8-K, filed on January 5, 2022 (SEC File No. 1-31993)).

Exhibit 2.1 Execution Version {N4469832.17} STOCK PURCHASE AGREEMENT BY AND AMONG MICHAEL V. PETILLO, THE 2020 AUDREY PETILLO FAMILY TRUST, THE MICHAEL V. PETILLO FAMILY TRUST, PETILLO LLC, PETILLO NY LLC, PETILLO MARYLAND INCORPORATED, PETILLO NJ HOLDINGS INCORPORATED, PETILLO NY HOLDINGS INCORPORATED, PETILLO MD HOLDINGS INCORPORATED, SELLERS REPRESENTATIVE and STERLING CONSTRUCTION COMPANY, INC

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

Exhibit 99.3 UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION On December 30, 2021, Sterling Construction Company, Inc., (?Sterling? or, the ?Company?) consummated the acquisition (the ?Acquisition?) of Petillo Incorporated and its related entities (collectively, ?Petillo?), for a base purchase price of $195.0 million, consisting of $175.0 million in cash and 759,447 Sterling common sh

We build and service the infrastructure that enables our economy to run, our people to move and our country to grow. STERLING ACQUIRES PETILLO, AN INDUSTRY LEADING SPECIALTY SITE DEVELOPMENT COMPANY January 6, 2022 2 DISCLOSURE: Forward-Looking State

We build and service the infrastructure that enables our economy to run, our people to move and our country to grow.

Audited combined financial statements of Petillo as of and for the year ended December 31, 2020

Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1 Exhibit 99.1

Unaudited combined financial statements of Petillo as of and for the nine months ended September 30, 2021

Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2 Exhibit 99.2

Regulation FD Disclosure, Financial Statements and Exhibits

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): January 5, 2022 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation

Third Amendment to Credit Agreement, dated December 29, 2021, by and among Sterling Construction Company, Inc., the subsidiaries of the Company party thereto as Guarantors, the Lenders party thereto and BMO Harris Bank N.A. as Administrative Agent (incorporated by reference to Exhibit 10.1 to Sterling Construction Company, Inc.’s Current Report on Form 8-K, filed on January 5, 2022 (SEC File No. 1-31993)).

Execution Version THIRD AMENDMENT TO CREDIT AGREEMENT THIS THIRD AMENDMENT TO CREDIT AGREEMENT (this ?Amendment?), dated as of December 29, 2021, is entered into by and among STERLING CONSTRUCTION COMPANY, INC.

Sterling Acquires Petillo, an Industry Leading Specialty Site Development Company

Exhibit 99.1 NEWS RELEASE For Immediate Release: January 5, 2022 Sterling Acquires Petillo, an Industry Leading Specialty Site Development Company ?One of the largest specialty site development companies in the Northeast ?Expansion of geographic footprint to cover blue chip e-commerce customers in all major East Coast markets ?Positions Sterling to be an industry leader on E-infrastructure special

Entry into a Material Definitive Agreement, Unregistered Sales of Equity Securities, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant, Completion of Acquisition or Disposition of Assets

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): December 29, 2021 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporatio

Sterling Acquires a Soil Stabilization Business in the Southeast

EXHIBIT 99.1 NEWS RELEASE For Immediate Release: December 28, 2021 Sterling Acquires a Soil Stabilization Business in the Southeast THE WOODLANDS, TX ? December 28, 2021 ? Sterling Construction Company, Inc. (NasdaqGS: STRL) (?Sterling? or ?the Company?) today announced that it has acquired Kimes & Stone (?Kimes?). Kimes provides a diversified services offering of soil stabilization for site devel

Regulation FD Disclosure, Financial Statements and Exhibits

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): December 28, 2021 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporatio

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2021 ☐ TRANSITION REPORT PURSUANT

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2021 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING CONSTRUCTI

Presentation slides, dated November 3, 2021

Exhibit 99.2

Sterling Reports Third Quarter 2021 Results EPS Continues to Outpace Expectations Increases 2021 Full Year Revenue and Net Income Guidance Delivered Record YTD Operating Cash Flow

Exhibit 99.1 NEWS RELEASE For Immediate Release: November 2, 2021 Sterling Reports Third Quarter 2021 Results EPS Continues to Outpace Expectations Increases 2021 Full Year Revenue and Net Income Guidance Delivered Record YTD Operating Cash Flow THE WOODLANDS, TX ? November 2, 2021 ? Sterling Construction Company, Inc. (NasdaqGS: STRL) (?Sterling? or the ?Company?) today announced financial result

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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 2, 2021 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation

Presentation slides, dated September 22, 2021

Exhibit 99.1

Regulation FD Disclosure, Financial Statements and Exhibits

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): September 21, 2021 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporati

STERLING CONSTRUCTION COMPANY, INC. ANNOUNCES ELECTION OF JULIE DILL TO ITS BOARD OF DIRECTORS

Exhibit 99.1 NEWS RELEASE For Immediate Release: September 1, 2021 STERLING CONSTRUCTION COMPANY, INC. ANNOUNCES ELECTION OF JULIE DILL TO ITS BOARD OF DIRECTORS THE WOODLANDS, TX ? September 1, 2021 ? Sterling Construction Company, Inc. (NasdaqGS: STRL) (?Sterling? or ?the Company?) today announced the election of Julie Dill to its Board of Directors, enlarging the Board to eight members, effecti

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

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): August 31, 2021 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation

Form of SEICP Long-Term Incentive Award Agreement (incorporated by reference to Exhibit 10.4 to Sterling Construction Company, Inc.’s Quarterly Report on Form 10-Q filed on August 3, 2021 (SEC File No. 1-31993)).

EXHIBIT 10.4 STERLING CONSTRUCTION COMPANY, INC. [Year] SEICP Long-Term Incentive Award Agreement This SEICP Long-Term Incentive Award Agreement (this "Agreement") is entered into between you, [Participant Name], and Sterling Construction Company, Inc. (the "Company") pursuant to the Company?s [Year] Senior Executive Incentive Compensation Program, a copy of a description of which has been furnish

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2021 ☐ TRANSITION REPORT PURSUANT TO S

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2021 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING CONSTRUCTION CO

Form of Senior Executive Incentive Compensation Program - Program Description (incorporated by reference to Exhibit 10.3 to Sterling Construction Company, Inc.’s Quarterly Report on Form 10-Q filed on August 3, 2021 (SEC File No. 1-31993)).

EXHIBIT 10.3 [Year] Senior Executive Incentive Compensation Program Program Description Introduction You have been selected to participate in the Company?s [Year] Senior Executive Incentive Compensation Plan (the ?SEICP? or ?Program?). The purpose of the SEICP is to advance the interests of the Company's stockholders by enhancing the Company's ability to attract, retain and motivate persons who ma

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): August 2, 2021 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation o

Sterling Reports Second Quarter 2021 Results Exceeds EPS Expectations Delivers Record Cash Flow from Operating Activities Increases 2021 Full Year Net Income Guidance

Exhibit 99.1 NEWS RELEASE For Immediate Release: August 2, 2021 Sterling Reports Second Quarter 2021 Results Exceeds EPS Expectations Delivers Record Cash Flow from Operating Activities Increases 2021 Full Year Net Income Guidance THE WOODLANDS, TX ? August 2, 2021 ? Sterling Construction Company, Inc. (NasdaqGS: STRL) (?Sterling? or the ?Company?) today announced financial results for the second

Presentation slides, dated August 3, 2021

Exhibit 99.2

Second Amendment to Credit Agreement, dated June 28, 2021, by and among Sterling Construction Company, Inc., the subsidiaries of the Company party thereto as Guarantors, the Lenders party thereto and BMO Harris Bank N.A. as Administrative Agent (incorporated by reference to Exhibit 10.1 to Sterling Construction Company, Inc.’s Current Report on Form 8-K, filed on June 30, 2021 (SEC File No. 1-31993)).

Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1 Exhibit 10.1

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Other Events

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 28, 2021 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or

Sterling Amends Existing Credit Agreement, Significantly Reducing Interest Expense and Enhancing Financial Flexibility

Exhibit 99.1 NEWS RELEASE For Immediate Release: June 30, 2021 Sterling Amends Existing Credit Agreement, Significantly Reducing Interest Expense and Enhancing Financial Flexibility THE WOODLANDS, TX ? June 30, 2021 ? Sterling Construction Company, Inc. (NasdaqGS: STRL) (?Sterling? or ?the Company?) today announced that it has amended its existing credit agreement with its lending group, led by BM

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

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): May 5, 2021 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

- S-8

As filed with the Securities and Exchange Commission on May 5, 2021. Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 25-1655321 (State or other jurisdiction of incorporation or organization

- S-8 POS

As filed with the Securities and Exchange Commission on May 5, 2021. Registration No. 333-204085 Registration No. 333-196457 Registration No. 333-135666 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO: FORM S-8 REGISTRATION STATEMENT NO. 333-204085 FORM S-8 REGISTRATION STATEMENT NO. 333-196457 FORM S-8 REGISTRATION STATEMENT NO. 333-135666

- S-8 POS

As filed with the Securities and Exchange Commission on May 5, 2021. Registration No. 333-204085 Registration No. 333-196457 Registration No. 333-135666 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO: FORM S-8 REGISTRATION STATEMENT NO. 333-204085 FORM S-8 REGISTRATION STATEMENT NO. 333-196457 FORM S-8 REGISTRATION STATEMENT NO. 333-135666

Sterling Construction Company, Inc. Amended and Restated 2018 Stock Incentive Plan (incorporated by reference to Exhibit 99.1 to Sterling Construction Company, Inc.’s Registration Statement on Form S-8, filed on May 5, 2021 (SEC File No. 1-31993)).

EXHIBIT 99.1 STERLING CONSTRUCTION COMPANY, INC. AMENDED AND RESTATED 2018 STOCK INCENTIVE PLAN 1. Purpose. The purpose of the Amended and Restated 2018 Stock Incentive Plan (the ?Plan?) is to increase stockholder value and advance the interests of the Company and its Subsidiaries by furnishing a variety of equity incentives designed to (a) attract, retain, and motivate key employees, officers, an

- S-8 POS

As filed with the Securities and Exchange Commission on May 5, 2021. Registration No. 333-204085 Registration No. 333-196457 Registration No. 333-135666 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO: FORM S-8 REGISTRATION STATEMENT NO. 333-204085 FORM S-8 REGISTRATION STATEMENT NO. 333-196457 FORM S-8 REGISTRATION STATEMENT NO. 333-135666

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2021 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING CONSTRUCTION C

Sterling Reports Record First Quarter 2021 Results Record First Quarter Revenue, Earnings, and Operating Cash Flow Backlog Reaches an All-Time High of $1.64 Billion

Exhibit 99.1 NEWS RELEASE For Immediate Release: May 3, 2021 Sterling Reports Record First Quarter 2021 Results Record First Quarter Revenue, Earnings, and Operating Cash Flow Backlog Reaches an All-Time High of $1.64 Billion THE WOODLANDS, TX ? May 3, 2021 ? Sterling Construction Company, Inc. (NasdaqGS: STRL) (?Sterling? or the ?Company?) today announced financial results for the first quarter 2

EX-99.2

Exhibit 99.2

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): May 3, 2021 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

- DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defin

- DEF 14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defin

- DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defin

Annual Report - 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING CONSTRUCTION COMPAN

Subsidiaries of the registrant.

Exhibit 21.1 Subsidiaries of the registrant Name State of Incorporation or Organization Texas Sterling Construction Co. Delaware Texas Sterling ? Banicki, JV LLC Texas Road and Highway Builders, LLC Nevada Road and Highway Builders Inc. Nevada RHB Properties, LLC Nevada Road and Highway Builders of California, Inc. California Sterling Hawaii Asphalt, LLC Hawaii Ralph L. Wadsworth Construction Comp

Executive Employment Offer dated July 27, 2020 between Sterling Construction Company, Inc. and Mark Wolf (incorporated by reference to Exhibit 10.6.1 to Sterling Construction Company, Inc.’s Form 10-K filed on March 5, 2021 (SEC File No. 1-31993)).

Exhibit 10.6.1 Exhibit 10.6.1

Sterling Reports Strong 2020 Fourth Quarter and Record Full Year Results Record Full Year Operating Cash Flow Drives $77.7 million of Debt Payments 2021 Midpoint EPS Guidance Calling for Growth of 22%

Exhibit 99.1 NEWS RELEASE For Immediate Release: March 2, 2021 Sterling Reports Strong 2020 Fourth Quarter and Record Full Year Results Record Full Year Operating Cash Flow Drives $77.7 million of Debt Payments 2021 Midpoint EPS Guidance Calling for Growth of 22% THE WOODLANDS, TX – March 2, 2021 – Sterling Construction Company, Inc. (NasdaqGS: STRL) (“Sterling” or the “Company”) today announced f

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): March 2, 2021 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation or

Presentation slides, dated March 3, 2021

Exhibit 99.2

SCHEDULE 13G

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 3 )* Sterling Construction Co Inc (Name of Issuer) Common Stock (Title of Class of Securities) 859241101 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to whic

SCHEDULE 13G

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1 )* Sterling Construction Company, Inc. (Name of Issuer) Common Stock (Title of Class of Securities) 859241101 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits - 8-K

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): December 23, 2020 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporatio

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits - 8-K

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): December 8, 2020 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation

Presentation slides, dated November 3, 2020

Exhibit 99.2

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

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 2, 2020 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation

Sterling Reports 2020 Third Quarter Results Strong Profitability and Cash Flow Further Enhance Liquidity Position Record Backlog Provides Visibility Into 2021 Growth

Exhibit 99.1 NEWS RELEASE For Immediate Release: November 2, 2020 Sterling Reports 2020 Third Quarter Results Strong Profitability and Cash Flow Further Enhance Liquidity Position Record Backlog Provides Visibility Into 2021 Growth THE WOODLANDS, TX – November 2, 2020 – Sterling Construction Company, Inc. (NasdaqGS: STRL) (“Sterling” or “the Company”) today announced financial results for the thir

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING CONSTRUCTI

STERLING CONSTRUCTION COMPANY, INC. ANNOUNCES ELECTION OF DWAYNE WILSON TO ITS BOARD OF DIRECTORS

Exhibit 99.1 NEWS RELEASE For Immediate Release: September 1, 2020 STERLING CONSTRUCTION COMPANY, INC. ANNOUNCES ELECTION OF DWAYNE WILSON TO ITS BOARD OF DIRECTORS THE WOODLANDS, TX – September 1, 2020 – Sterling Construction Company, Inc. (NasdaqGS: STRL) (“Sterling” or “the Company”) today announced the election of Dwayne Wilson to its Board of Directors, enlarging the Board to eight members, e

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits - 8-K

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): September 1, 2020 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporatio

August 4, 2020 conference call transcript

Financial Statements and Exhibits, Results of Operations and Financial Condition

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): August 4, 2020 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation o

Sterling Reports 2020 Second Quarter Results Recent Acquisition and Base Business Performance Drive Record Results Raises Full Year Revenues and Income Outlook

Exhibit 99.1 NEWS RELEASE For Immediate Release: August 3, 2020 Sterling Reports 2020 Second Quarter Results Recent Acquisition and Base Business Performance Drive Record Results Raises Full Year Revenues and Income Outlook THE WOODLANDS, TX – August 3, 2020 – Sterling Construction Company, Inc. (NasdaqGS: STRL) (“Sterling” or “the Company”) today announced financial results for the second quarter

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

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): August 3, 2020 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) Delaware 001-31993 25-1655321 (State or other jurisdiction of incorporation o

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 1-31993 STERLING CONSTRUCTION CO

Presentation slides, dated August 4, 2020

Exhibit 99.2

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

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 2, 2020 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) DELAWARE 001-31993 25-1655321 (State or other jurisdiction of incorporation or

-

CORRESP May 13, 2020 VIA EDGAR United States Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.

Financial Statements and Exhibits, Results of Operations and Financial Condition

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): May 5, 2020 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) DELAWARE 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

May 5, 2020 conference call transcript.

Exhibit 99.1

Submission of Matters to a Vote of Security Holders

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): May 6, 2020 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) DELAWARE 001-31993 25-1655321 (State or other jurisdiction of incorporation or o

Sterling Reports First Quarter 2020 Results Record EBITDA (1) Record Backlog of $1.2 billion and Backlog Gross Margin of 12.7%

Exhibit 99.1 NEWS RELEASE For Immediate Release: May 4, 2020 Sterling Reports First Quarter 2020 Results Record EBITDA (1) Record Backlog of $1.2 billion and Backlog Gross Margin of 12.7% THE WOODLANDS, TX – May 4, 2020 – Sterling Construction Company, Inc. (NasdaqGS: STRL) (“Sterling” or “the Company”) today announced financial results for the three months ended March 31, 2020. Consolidated First

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

Exhibit 99.2 UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION On October 2, 2019, pursuant to the Equity Purchase Agreement with Greg K. Rogers, Philip T. Travis, as trustee of the Lorin L. Rogers 2018 Trust, Kimberlin Rogers 2018 Trust, Gregory K. Rogers 2018 Trust and Mary A. Rogers 2018 Trust, LK Gregory Construction, Inc., Plateau Excavation, Inc. and DeWitt Excavation, LLC (collec

Statement of Eligibility and Qualification on Form T-1 of U.S. Bank National Association as trustee under Form of Indenture.

EX-25.1 Exhibit 25.1 SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE ☐ Check if an Application to Determine Eligibility of a Trustee Pursuant to Section 305(b)(2) U.S. BANK NATIONAL ASSOCIATION (Exact name of Trustee as specified in its charter) 31-0841368 I.R.S. Employer

- S-3

S-3 Table of Contents As filed with the Securities and Exchange Commission on May 5, 2020 Registration No.

Financial Statements and Exhibits, Other Events

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): May 5, 2020 STERLING CONSTRUCTION COMPANY, INC. (Exact name of registrant as specified in its charter) DELAWARE 001-31993 25-1655321 (State or other jurisdiction of incorporation or o