Tony Cocker, who has led the UK arm of Eon since September 2011, will leave the company to pursue a portfolio career at the end of July.
He will be replaced by the current chief executive of Eon Climate and Renewables Michael Lewis, who will become Eon UK chief executive on 10 April.
Cocker worked at the German-owned energy company for more than 20 years. On his retirement, he said: “Having spent five years in post I decided it was time to take on new challenges and I am personally delighted that Michael is to succeed me.
“I will, of course, miss my colleagues, as from the very first day I have witnessed firsthand the pride, determination and dedication our team put in to helping customers and striving to improve and innovate.”
Eon chief executive Johannes Teyssen said: “I’d like to thank Tony Cocker for his outstanding contribution, not only to our UK business but also to our company as a whole.
“During his time leading our UK business, Tony helped make customer focus part of our DNA. The management board wishes Tony and his family all the best for the future.”
Incoming Eon UK chief executive Lewis stated he is looking forward to taking up his new position. He added: “I am delighted to be appointed to lead Eon UK and I look forward to joining what I already know to be an excellent team.
“It is a fascinating time to take on this challenge and a real privilege to follow Tony, who has ensured Eon UK is leading the change needed to ensure we live up to our purpose of improving peoples’ lives.”