The Thrift Savings Plan (TSP) is an essential component of the three-tiered Federal Employees Retirement System (FERS): A FERS annuity, and Social Security and TSP payments that provide retirement income. TSP investments are also an income source for many retirees who receive Civil Service Retirement System benefits.
By participating in the TSP, postal and other federal workers have an opportunity to save part of their pre-tax income for retirement — and receive matching contributions from the Postal Service. You can decide how much of your pay to put in your TSP account, which funds to invest it in, and how you want to receive your money when you retire.
Additional information about the features and benefits of the TSP is available from your personnel office or from the OPM or TSP websites.