Steve Bee is to leave Scottish Life at the end of January, after 12 years with the firm.
Bee, head of pensions strategy at Royal London's pensions arm, is one of the industry's most well known commentators on retirement issues.
He will step down from his role on 20 January 2010 to join a new venture, which he says will not compete with Scottish Life.
Chief executive of Scottish Life, John Deane, says: "They say that all good things must come to an end and Steve has been a very good thing for Scottish Life.
"Steve has helped Scottish Life become a major player in the market, with real product innovation and an excellent service proposition. We'll be giving him a good send off when he goes, with our very best wishes for the future."
Bee adds: "It was an incredibly difficult decision that I had to take to leave Scottish Life after over 12 years with the business. I can't think of any other provider company that would have given me the freedom and the support to do what I've been doing.
"I've had some really memorable times, especially ‘on the road', meeting IFAs throughout the UK and discussing pensions with them."
Caring for children and elderly relatives
Similar to June 2007
Square Mile’s series of informal interviews
Fine reduced to £60,000
Two roles created