RETIREMENT · FEDERAL EMPLOYEES

TSP Calculator

Project your Thrift Savings Plan (TSP) contributions and balance across all five funds — G, F, C, S, and I. See how your contribution rate, agency match, and fund allocation affect your retirement nest egg.

LAST REVIEWED · APR 28, 2026 · BY CALCMADE EDITORIAL
Educational tool, not advice. Projections rely on assumptions about returns, inflation, and contributions; actual results vary. Consult a licensed financial advisor before acting on the result. See disclaimer and methodology.
You need
$1,057,488
Est. cost
$155,473
TSP DetailsReset
Current balance
$50,000
$0$2M
Annual salary
$80,000
$20K$250K
Contribution rateOf salary
10%
0%100%
Years to grow
25 yrs
140
Fund Allocation
G FundGovt securities ~2.5%
10%
0%100%
F FundBonds ~3.5%
10%
0%100%
C FundS&P 500 ~10%
40%
0%100%
S FundSmall/mid ~10.5%
20%
0%100%
I FundInternational ~7%
20%
0%100%

How the TSP calculator works

The Thrift Savings Plan offers five core funds, each tracking a different index. This calculator projects your balance in each fund based on historical average returns, your contribution rate, and your fund allocation.

TSP contribution limits for 2026

The TSP follows the same elective deferral limit as a 401(k). For 2026:

  • $23,500 regular elective deferral limit
  • +$7,500 standard age-50 catch-up (total $31,000)
  • +$11,250 SECURE 2.0 enhanced catch-up for ages 60–63 (total $34,750)

Contribute at least 5% of basic pay to capture the full FERS agency match — leaving anything below 5% on the table is the most common TSP mistake.

The agency match for FERS employees

FERS-covered employees get an automatic 1% agency contribution regardless of whether they contribute. On top of that, the agency matches:

  • Dollar-for-dollar on the first 3% of pay you contribute
  • $0.50 on the dollar for the next 2%

So a 5% personal contribution earns a 5% agency contribution, for an effective 10% total going into the TSP. CSRS employees receive no match — the calculator’s contribution figure is your full deposit in that case.

The five TSP funds

  • G Fund — Government securities (~2.5% avg). Lowest risk, guaranteed principal.
  • F Fund — Bond index (~3.5% avg). Low risk, tracks Bloomberg Barclays U.S. Aggregate.
  • C Fund — S&P 500 index (~10% avg). Core large-cap equity exposure.
  • S Fund — Small/mid-cap index (~10.5% avg). Higher growth potential, more volatility.
  • I Fund — International index (~7% avg). Developed market diversification.

Lifecycle (L) funds

If you’re not sure how to allocate, TSP’s Lifecycle funds automatically shift from stocks to bonds as you approach retirement. This calculator models individual fund choices for more granular control.

Methodology. Projects each fund’s balance independently using historical average returns: G Fund (2.5%), F Fund (3.5%), C Fund (10%), S Fund (10.5%), I Fund (7%). Contributions allocated proportionally to the selected fund allocation. Annual compounding applied per fund.

Sources

  • TSP.gov — Fund Performance and Historical Returns
  • Federal Retirement Thrift Investment Board annual reports
  • IRS Notice 2025-67 — 2026 contribution limits ($23,500 elective deferral; $31,000 with age-50 catch-up)
  • SECURE 2.0 Act §109 — enhanced catch-up for ages 60–63 ($11,250 in 2026)
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Frequently asked questions

What is the maximum TSP contribution for 2026? +
$23,500 in regular elective deferrals, plus a $7,500 catch-up if you’re 50 or older (for a total of $31,000), or an enhanced $11,250 catch-up if you’re ages 60–63 under SECURE 2.0 (total $34,750). The agency match is on top of these limits.
How much should I contribute to TSP to get the full match? +
Contribute at least 5% of your basic pay. FERS employees receive a 1% automatic agency contribution plus a match of dollar-for-dollar on the first 3% and $0.50/dollar on the next 2% — capping out at 5% in agency money when you contribute 5% yourself.
What’s the best TSP fund allocation? +
There’s no universal best. A common aggressive allocation is 60% C, 20% S, 20% I. A moderate one is 40% C, 15% S, 15% I, 20% F, 10% G. Your ideal mix depends on your age and risk tolerance.
Should I use the G Fund? +
The G Fund guarantees your principal but barely keeps up with inflation. It’s appropriate for money you’ll need in the next 1–3 years, but holding too much in G over decades significantly reduces growth.
Does the TSP match contributions? +
FERS employees receive an automatic 1% agency contribution plus a match of up to 4% (dollar-for-dollar on the first 3%, 50 cents per dollar on the next 2%). Contribute at least 5% to get the full match. CSRS employees do not receive a match.