Employees participate in one of three pension programs based on the starting date of employment with the federal government. Employee and employer contributions are made to the Civil Service Retirement System (CSRS), the Dual Civil Service Retirement System/Social Security (Dual CSRS), or the Federal Employees Retirement System (FERS), all of which are administered by the OPM. Employees may also participate in the Thrift Savings Plan (TSP), a defined contribution retirement savings and investment plan, administered by the Federal Retirement Thrift Investment Board.
