Table of Contents 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 September 30, 2023 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES ☐ EXCHANGE ACT OF 1934 Commission file number 000-26591 RGC Resources, Inc. (Exact name of Registrant as Specified in its Charter) Virginia 54-1909697 (State or Other Jurisdiction of Incorporation o ...