Ameren Corp. is promoting Warner Baxter to president of the St. Louis-based utility, effective immediately, and he'll become CEO this spring.
Baxter is a longtime executive at Ameren. He succeeds Thomas Voss, who will retire on July 1.
Ameren said Tuesday that Baxter also has been elected to the board of directors. He will become chief executive on April 24 -- the day Voss will become Ameren's executive chairman.
Baxter was executive vice president and chief financial officer of Ameren from 2003 to 2009, and has since served as chief executive of its Ameren Missouri division.
Voss, who is 66, has been president and CEO of Ameren Corp. since 2009 and chairman since 2010.
Ameren provides electric and natural gas services in parts of Missouri and Illinois.