Racing car enthusiast Tom Alexander, who helped to found Virgin Mobile in Trowbridge in the late 90s, is looking forward to more time with his family in Somerset after resigning as boss of Bristol-based Everything Everywhere "to spend more time with his children".
It follows growing concerns by the mobile phone giant's joint owners, France Telecom and Deutsche Telekom, over EE's financial performance since the two networks merged last year.
While Vodafone and O2 are enjoying strong revenue growth, EE has struggled to keep pace as it implements a far-reaching plan to slash costs at Britain’s largest mobile phone group.
One EE insider told the Daily Mail: "We’re the biggest but not the best – there are others in a much stronger position."
He said in a statement: "It's been my privilege to serve Everything Everywhere these past 12 months, and Orange before that. I'm proud of what we've accomplished: we conducted a rapid integration of the new company, completing a company-wide restructuring, and maintained good commercial momentum throughout, delivering record retention levels and growth on our contract customer base across both brands.
"There is never an easy time to leave a company that you care deeply for but, for personal reasons, I feel now is a good moment to step back."
Mr Alexander pocketed more than £20m from the flotation of Virgin Mobile in 2004.