A rider on a variable annuity, which guarantees the minimum amount received by the annuitant after the accumulation period, or a set period of time, is either the amount invested or is locked in gain. This protects the value of the annuity and the annuitant from market fluctuations.

This benefit is optional to an annuity for an added cost, which varies by each firm. The GMAB will be used only if the market value of the annuity is below the minimum guaranteed value. In some cases, the cumulative costs of the benefit are returned to the annuity if the annuity value is higher than the minimum, removing the need to use the rider.