"...One of the least understood aspects of federal retirement policy involves capturing credit for military service. The military began deducting Social Security from military wages on January 1, 1957. Congress enacted a law in 1982 giving employees the opportunity to make a deposit into their civilian retirement system for active military time served after 1956.
Individuals who make the deposit are entitled to credit for the military service under both the Social Security system and the applicable civilian retirement system..."