The FERS basic retirement benefit often includes a “supplement” to take the place of a Social Security retirement benefit when an employee retires with an unreduced, immediate benefit, but is younger than the age to qualify for Social Security retirement.
FERS was designed to be a three-tiered retirement system based on participation in Social Security, Thrift Savings Plan and a government retirement benefit. The FERS retirement benefit is smaller than the one paid under CSRS for any given length of service and level of compensation as the older CSRS system was designed to “stand alone” without the additional benefits of Social Security or the TSP.
The FERS supplement provides a “bridge” to Social Security entitlement for certain employees who retire younger than age 62. It is equal to the Social Security benefit that they earned while employed by the federal government and enrolled in FERS.