Aberdeen Asset Management has bought the contract to manage £5.5bn in funds from Windsor Life in an £86m deal.
The move will see Aber-deen's funds under management jump by 19 per cent from £28.5bn to £34bn.
The deal could help offset the expected loss of £10.5bn of funds managed for Scottish Provident when the life office's deal with Abbey National is completed. Abbey aims to transfer ScotProv's funds to its own investment managers.
The new contract will generate an annual income of £11m for Aberdeen. Windsor policyholders will benefit from reduced charges. The deal will run for at least 10 years.
This contract will also manage the investment funds of Life Assurance Holding Corporation, the parent of Windsor and a holding company which acquires and rationalises life insurance companies and portfolios.
LAHC was set up in 1994 by St James's Place Capital. Windsor is its principal subsidiary. Windsor investment management staff will transfer to Aberdeen, as will the ownership of LAHC's unit trust company which has funds under management of £7.8m.
Aberdeen will issue 15 million new ordinary shares and give loan notes valued at £10m to LAHC. Based on its share price on April 11, the deal is worth £86m.
Aberdeen chief executive Martin Gilbert says: “This deal grants us a long-term contract to manage £5.5bn of assets that are not only very stable but also represent a significant revenue stream for Aberdeen, with minimal inc-remental costs.”