The move, announced in a joint statement on May 27, comes after stock-market declines and low interest rates have squeezed the guarantees of segregated funds, which are similar to mutual funds but include insurance features such as death benefits and promises that investors will receive minimum amounts at maturity.

Sun Life, which provides the insurance, and CI, which manages and markets the funds, said the changes "ensure that the products continue to provide a wide selection of investment choices and guarantee options that meet the needs of investors."

Effective July 31, or later under some segregated fund contracts, Sun Life and CI will increase the insurance fees and limit certain premium deposits.

Price increases will range up to 0.3 per cent, depending on each fund's asset class, guarantee and other factors.

New deposits will no longer be accepted in some segregated fund products, including the SunWise Elite Full Guarantee Option, which promises to return no less than 100 per cent of an investor's principal on maturity or death.

New money will still be accepted in similar SunWise funds with a 75 per cent money-back guarantee, but new contracts will have to have at least 30 per cent of the portfolio in fixed-income investments.