TSP Calculator

The TSP is the federal government's retirement savings plan, the public-sector equivalent of a private 401(k). It is open to federal civilian employees and members of the uniformed services. You contribute pre-tax (Traditional) or after-tax (Roth) money, choose from a small menu of very low-cost funds, and your agency or service adds matching contributions if you are covered by FERS or the Blended Retirement System. The TSP is run by the Federal Retirement Thrift Investment Board (tsp.gov).

The elective-deferral limit for 2026 is $24,500 for workers under 50, the same limit that applies to 401(k) and 403(b) plans. If you are age 50 to 59 or 64+, you can add an $8,000 catch-up (total $32,500). Under SECURE 2.0, ages 60 to 63 get a larger super catch-up for a total of $35,750. Agency and matching contributions do not count against your elective-deferral limit; they fall under the separate $72,000 annual-additions limit (IRS Notice 2025-67).

If you are covered by FERS or the military Blended Retirement System, your agency or service contributes two things. First, an automatic 1% of your base pay, paid whether or not you contribute anything yourself. Second, a match on your own contributions: dollar-for-dollar on the first 3% of pay you contribute, then 50 cents on the dollar for the next 2%. Contribute at least 5% and you collect the full agency contribution of 5% of pay (1% automatic plus a 4% match). Anything you contribute above 5% is not matched, though it still grows tax-advantaged. CSRS employees do not receive agency contributions.

Traditional TSP contributions are pre-tax, lowering your tax bill now, and withdrawals are taxed later. Roth TSP contributions are after-tax, with no break now but tax-free qualified withdrawals later. One detail unique to the TSP: your agency and matching contributions always go to your Traditional balance, even if your own contributions are Roth. Many federal employees who expect a pension plus Social Security in retirement find their tax bracket stays high, which often favors Roth. Our Roth 401(k) calculator models the same Roth versus Traditional trade-off.

The TSP offers five core funds: the G Fund (government securities), F Fund (bonds), C Fund (large-cap U.S. stocks, tracking the S&P 500), S Fund (small and mid-cap U.S. stocks), and I Fund (international stocks). It also offers Lifecycle (L) funds, which blend the core funds and shift toward bonds as your target date approaches. The fund-mix selector in this calculator applies a typical long-run return for each, but past performance does not guarantee future results. For a diversified long horizon, many investors model 7% to 8%; for a conservative or near-retirement mix, lower (fund details at tsp.gov).

The TSP is one of the lowest-cost retirement plans in the world. Net expense ratios run only a few hundredths of a percent per year, a fraction of what a typical private-sector 401(k) charges. Because fees compound against you over a career, this gap can leave a federal employee with tens of thousands of dollars more at retirement than an equivalent private-sector saver in a higher-cost plan. Even after you leave federal service, many people keep money in the TSP specifically to retain those rock-bottom costs.

Yes. You are not required to move your money when you separate or retire. You can leave it in the TSP and keep its low fees, take partial or installment withdrawals, roll it into an IRA or a new employer's plan, or buy an annuity. Because the TSP's costs are so low, leaving the balance in place is often the better choice rather than rolling it into a higher-cost IRA. Review your options carefully before moving money, and confirm any rollover is done as a direct transfer to avoid taxes and penalties.

Generally you can take penalty-free withdrawals after age 59½, the same as a 401(k). If you separate from federal service in or after the year you turn 55 (age 50 for certain public-safety roles), the 401(k)-style "rule of 55" lets you access your TSP penalty-free earlier. Withdrawals from your Traditional balance are taxed as ordinary income; qualified Roth withdrawals are tax-free. Required minimum distributions begin at age 73. Unlike a 457(b), the TSP does carry the standard 10% early-withdrawal penalty before these ages.