Is Thrift Savings Plan A Retirement Plan? 
The Thrift Savings Plan -LRB- TSP -RRB- is a qualified defined contribution plan for US civil service employees , retirees and members of the uniformed services . The TSP is part of the Federal Employees Retirement System -LRB- including FERS annuity and Social Security -RRB- . The TSP can also covered under the Civil Service Retirement System -LRB- CSRS -RRB- . 