About the TSP Calculator
This TSP calculator projects how your Thrift Savings Plan account can grow by retirement. It adds your own contributions, the agency or service automatic 1% contribution, and the agency matching contributions that FERS employees and Blended Retirement System (BRS) members receive — dollar for dollar on the first 3% of pay and 50 cents per dollar on the next 2%.
It is built for federal civilian employees, members of the uniformed services and anyone comparing TSP contribution rates. Enter your current balance, salary, the percentage you contribute, expected pay raises and an average annual return. The calculator caps your own contributions at the 2026 elective deferral limit of $24,500 and shows whether you are leaving free matching money on the table.
Contributions are added at the end of each year and returns compound annually; your salary grows by the raise you enter. CSRS employees receive no agency contributions, so choose “No agency contributions” for them; BRS members should check their service dates, because matching does not apply in every year of service. Catch-up contributions for age 50+ ($8,000 in 2026, or $11,250 at ages 60–63) are separate and not included. Returns are assumptions, not a forecast of the G, F, C, S, I or L funds.
With the default inputs, the projected tsp balance is $604,408.90. Change any value above to recalculate instantly.
How to use the tsp calculator
- 1Enter your current TSP balance and annual basic pay.
- 2Enter the percentage of pay you contribute (traditional plus Roth).
- 3Choose FERS/BRS to include agency contributions, or none for CSRS.
- 4Set expected raises, an average return and years to retirement.
- 5Review the projected balance and check the note on missed matching.
Formula and method
FERS employees and BRS members receive an agency automatic contribution of 1% of basic pay whether or not they contribute, plus matching contributions of 100% on the first 3% of pay they contribute and 50% on the next 2%. Contributing 5% therefore earns the maximum 5% from the agency — a total of 10% of pay going into the TSP.
Each year the calculator grows the previous balance by the expected return, then adds your contribution (capped at the elective deferral limit L) and the agency contributions based on that year’s salary. Salary rises by your raise assumption every year. Agency contributions do not count toward your $24,500 limit.
- p
- Your contribution rate
- Sₜ
- Basic pay in year t
- r
- Expected annual return
- L
- Elective deferral limit
- g
- Annual pay raise
Worked examples
FERS employee, $75,000 pay, 5% contribution, 25 years
At 5% of $75,000 you contribute $3,750 in the first year and the agency adds another $3,750 (1% automatic + 4% match). With 2% raises and 6% returns over 25 years you contribute about $120,100, the agency adds the same, and the account grows to about $604,400.
Only contributing 2%
Contributing 2% of $60,000 ($1,200 a year) earns 1% automatic plus a 2% match, $1,800. After 30 years at 7% the balance is about $283,400. Raising the contribution to 5% would capture another $1,200 a year of free agency money.
High earner hitting the limit
20% of $150,000 would be $30,000, but contributions are capped at $24,500 a year. Your capped contribution is still over 5% of pay, so the agency adds the full 5%, $7,500 a year. After 10 years at 6%, $100,000 grows to about $600,900.
Frequently asked questions
How much does the government match in the TSP?+
FERS employees and BRS members get an automatic 1% of basic pay plus a match of 100% on the first 3% they contribute and 50% on the next 2%. Contributing 5% earns the maximum 5% from the agency.
What is the TSP contribution limit for 2026?+
The elective deferral limit for 2026 is $24,500 for traditional and Roth TSP contributions combined. Participants 50 and older can add $8,000 of catch-up contributions, or $11,250 in the years they turn 60 to 63, and catch-up money counts toward the 5% match. Agency contributions do not count toward the $24,500.
Should I pick traditional or Roth TSP?+
Traditional TSP lowers your taxable income now; Roth TSP is taxed now but qualified withdrawals are tax-free. Agency contributions always go into the traditional balance. Your current versus expected retirement tax rate is the main deciding factor.
What return should I assume for the TSP?+
It depends on your fund mix. The G Fund tracks Treasury rates while the C, S and I Funds are stock index funds with higher long-run returns and more volatility. Many planners use 5%–7% for a stock-heavy mix and lower for a conservative L Fund.
Do I get the TSP match if I contribute to Roth TSP?+
Yes. Matching is based on the total percentage you contribute, whether traditional or Roth. The agency match itself is deposited into your traditional balance.
Results are estimates for educational purposes and are not financial advice. Rates, fees and terms vary — confirm with your lender or a licensed advisor before making decisions.