UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-K (Mark One) Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 ☒ For the fiscal year 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 No. 001-15461 MATRIX SERVICE COMPANY (Exact name of registrant as specified in its charter) Delaware 73-1352174 (State or other jurisdiction of (I.R ...