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
	Filed by 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)) ☐ Definitive Proxy Statement ☒ Definitive Additional Materials ☐ Soliciting Material under §240.14a-12 MGE Energy, Inc. (Name of Registrant as Specified In Its Charter) (Name of Person(s) Filing Proxy Statement, if other than the Registrant) Check the appropriate box: ☒ No Fee Required ☐ Fee paid previously with preliminary materials ☐ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a6(i)(1) and 0-11

Additional information mailed to MGE Energy shareholders on or about April 4, 2025.