Minimum pension that a defined benefit scheme must provide as a condition of contracting out for pre-6 April 1997 service. GMP does not apply to money purchase contracted out schemes as the granting of protected rights is the relevant contracting out provision. Where all service is post-5 April 1997 the members’ benefits are protected by limited price indexation (LPI). Where service is pre- and post-5 April 1997, benefits are affected by GMP and LPI respectively.