(Mark One) ☒QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934For the quarterly period endedMarch31, 2026 orTRANSITIONREPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934For the transition period from ___________ to ___________ Tutor Perini Corporation (Exact name of registrant as specified in its charter)MASSACHUSETTS 04-1717070 (I.R.S. Employer Identification No.) (State or other jurisdiction ofincorporation or organization) 91342-1093 15901 OLDEN STREET,SYLMAR,CALIFORNIA (Zip Code) (Address of principal executive offices) (818)362-8391(Registrant’s telephone number, including area code)None(Former name, former address and former fiscal year, if changed since last report) Securities registered pursuant to Section 12(b) of the Act: Indicate by check mark whether the registrant (1)has filed all reports required to be filed by Section13 or 15(d)of the Securities Exchange Actof 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2)has been subject tosuch filing requirements for the past 90 days. Yes☒No☐ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant toRule405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required tosubmit such files). Yes☒No☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reportingcompany, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and“emerging growth company” in Rule12b-2 of the Exchange Act. If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying withany new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule12b-2 of the Exchange Act). Yes☐No☒ The number of shares of common stock, $1.00 par value per share, of the registrant outstanding at April30, 2026 was 52,614,703. TUTORPERINI CORPORATION AND SUBSIDIARIES TABLE OF CONTENTS PartI.Financial Information:Item 1.Financial Statements:Condensed Consolidated Statements of Income for the Three Months EndedMarch 31,2026 and 2025(Unaudited)3Condensed Consolidated Statements of Comprehensive Income for the Three MonthsEndedMarch 31, 2026 and 2025(Unaudited)4Condensed Consolidated Balance Sheets as ofMarch 31, 2026and December31, 2025(Unaudited)5Condensed Consolidated Statements of Cash Flows for the Three Months Ended March31, 2026 and 2025(Unaudited)6Notes to Condensed Consolidated Financial Statements (Unaudited)7Item 2.Management’s Discussion and Analysis of Financial Condition and Results of Operations30Item 3.Quantitative and Qualitative Disclosures About Market Risk39Item 4.Controls and Procedures39PartII.Other Information:Item 1.Legal Proceedings40Item 1A.Risk Factors40Item 2.Unregistered Sales of Equity Securities and Use of Proceeds40Item 4.Mine Safety Disclosures40Item 5.Other Information40Item 6.Exhibits41Signature42 TUTOR PERINI CORPORATION AND SUBSIDIARIESCONDENSED CONSOLIDATED STATEMENTS OF INCOME UNAUDITED TUTOR PERINI CORPORATION AND SUBSIDIARIESCONDENSED CONSOLIDATEDSTATEMENTS OF COMPREHENSIVE INCOME UNAUDITED Three Months EndedMarch 31, TUTOR PERINI CORPORATION AND SUBSIDIARIESCONDENSED CONSOLIDATEDBALANCE SHEETS UNAUDITED TUTOR PERINI CORPORATION AND SUBSIDIARIESCONDENSED CONSOLIDATEDSTATEMENTS OF CASH FLOWS UNAUDITED Three Months Ended March 31, TUTOR PERINI CORPORATION AND SUBSIDIARIESNOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS UNAUDITED (1)Basis of Presentation The Condensed Consolidated Financial Statements do not include footnotes and certain financial information normally presentedannually under generally accepted accounting principles in the United States (“GAAP”). Therefore, they should be read in conjunctionwith the audited consolidated financial statements and the related notes included in Tutor Perini Corporation’s (the “Company”)Annual Report on Form 10-K for the year ended December31, 2025. The results of operations for the three months ended March31,2026 may not be indicative of the results that will be achieved for the full year ending December31, 2026. In the opinion of management, the accompanying unaudited Condensed Consolidated Financial Statements reflect all adjustments,including those of a normal recurring nature, necessary to present fairly the Company’s condensed consolidated financial position as ofMarch31, 2026 and its condensed consolidated statements of income and cash flows for the interim periods presented. Intercompanybalances and transactions have been eliminated. Certa