Charles Gregson, chairman of St. James's Place, is stepping down from his role at the end of the year to be replaced by Sarah Bates.
Bates is currently a senior independent non-executive director at the group and will assume her new role from 1 January.
Gregson joined the board in January 2010 and has been chairman from 1 January 2012. He is stepping down to devote more time to his other directorships.
He said: "It has been a pleasure to have served as chairman of St. James's Place during what has been an exceptional period of growth for the group.
"I am confident that St. James's Place will be in excellent hands with Sarah as its chairman, whose experience and skills will be a great asset."
Mike Power, independent non-executive director, is also stepping down from the board, but will remain on the board of the group's Dublin-based life company.
The board will also gain two new non-executive directors - Simon Jeffreys and Roger Yates - from the start of the new year.
Jeffreys is currently chief operating officer of Wellcome Trust and a non-executive director at Henderson International Income investment trust and two other groups.
Yates is currently non-executive chairman of Pioneer Global Asset Management and holds a number of other directorship roles.
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