Old Mutual's chairman Patrick O’Sullivan will leave the company after its demerger and join Saga in the same role.
Irishman Mr O’Sullivan has been chairman and a non executive director of Old Mutual since 2010, but will leave the business when the "managed separation" of the company is completed.
The managed separation has already seen the single strategy funds business of Old Mutual Global Investors being sold to a consortium led by the unit’s chief executive, the fund manager Richard Buxton.
Meanwhile Old Mutual Wealth will list on the London Stock Exchange "at the earliest opportunity" after Old Mutual's 2017 full year results are published and rebrand as Quilter.
Old Mutual Wealth is retaining the multi-asset funds part of the business when it demerges from its South African parent.
Mr O 'Sullivan has previously worked at Zurich Insurance Group for more than a decade.
His appointment as chairman of Saga will take effect from Tuesday 1 May.
Saga provides a range of products for the over-50s, including financial services products, including insurance products and an investment platform.