If you're covered by the Civil Service Retirement System (CSRS) or are a member of the uniformed services, the TSP is a supplement to your CSRS annuity or military retired pay.

Do all federal employees have a TSP?

Learn more about TSP. If you are a federal employee covered by the Federal Employees' Retirement System (FERS) or the Civil Service Retirement System (CSRS), you may make TSP contributions immediately upon employment. ... All eligible employees are automatically enrolled in TSP at a five percent contribution rate.

Is TSP mandatory for federal employees?

Though the Thrift Savings Plan can provide you with a source of monthly income after retirement, it is different from the other two income sources that you will likely have (i.e., your FERS annuity and Social Security). ... There is no requirement that you contribute to the TSP at any time in your career.