A guaranteed minimum income benefit guarantees a floor on future annuitized income based on a rider benefit base. The base usually grows by a fixed roll-up or step-ups, but it is not a cash value and generally requires annuitization to access. Withdrawals can reduce the base, and fees apply. GMIB trade flexibility for income certainty at a future retirement date.

Pre-retirees track GMIB bases and plan annuitization dates. Advisors compare GLWB alternatives that provide lifetime income without giving up liquidity and model tax outcomes under each path.