Mutual Scottish Friendly has completed the acquisition of a back book of life and pension policies from financial services provider Canada Life.
The deal has seen its assets under management (AUM) increase by £2.4bn to more than £5bn. Its membership has increased by some 127,000.
Scottish Friendly said it would ensure all transferring customer policies received the "highest standards of care" during the transition period.
The companies first announced the deal to sell the closed book of business in June last year.
Scottish Friendly chief executive Jim Galbraith (pictured) said: "This is a landmark acquisition for Scottish Friendly and helps to consolidate us as a leading mutual and a significant player in UK financial services."
He said the acquisition formed part of its "three-pronged strategy of organic growth" to deliver the strongest growth and customer care for its members.
"We are delighted to have completed this process and welcome transferring Canada Life customers to Scottish Friendly."
Canada Life managing director and insurance division executive director Richard Priestley said the move was "excellent" for both organisations.
"Scottish Friendly has a great reputation in this area which gives us confidence that customers will be in good hands," he said.
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