Skip to main content
BeyondGov

TSP growth, contribution and match calculator

Project your balance to retirement, set a 2026 paycheck pace, and see employee deposits, Agency Automatic (1%) Contributions, matching and investment growth as separate lines.

Rule snapshot
Reviewed
Primary sources
TSP.gov and IRS 2026 limits · OPM match rules
Privacy
Inputs stay in this browser — no TSP account login

Your TSP scenario

Build a contribution-to-retirement plan

Start with current account and payroll facts. The return, inflation and future-limit values remain editable assumptions.

Account and retirement

Use the account balance as of today; it already includes all activity through that date.

Use TSP-eligible basic pay, not total compensation or overtime.

Determines age at the end of 2026 and the applicable catch-up limit.

The projection ends at the beginning of the year you reach this age.

FERS agency contributions

Select yes only if this civilian account receives the FERS automatic 1% and matching contributions. BRS and uniformed-service timing are outside this model.

Employee contribution election

Choose how your payroll election is expressed. All modes stop at the applicable annual employee limit.

2026 payroll position

Payroll calendar

Use the number of salary payments on your agency's 2026 calendar.

Include the next paycheck that can still accept a changed election; use 0 after the final 2026 paycheck.

Traditional and Roth employee deposits share one limit. This amount is not added to your balance again.

Aggregate 2025 TSP-eligible Medicare wages across all federal W-2s and payroll offices. Above $150,000—not equal to it—makes 2026 catch-up deposits Roth.

Projection assumptions

These are planning assumptions, not federal forecasts. Expected return should be net of investment expenses.

One constant net-return scenario; actual TSP returns will vary.

Applied once per modeled year to future basic pay.

Used only to translate the retirement balance into today's dollars.

An illustrative annual growth rate for future IRS limits, not an IRS forecast.

Projection results

Add your TSP scenario

Complete the account, contribution, payroll, and assumption fields to see the retirement projection.

Exact for 2026

Employee contribution limits

Age is measured on December 31, 2026. Traditional and Roth employee contributions share these limits. Agency money is displayed separately.

2026 TSP employee contribution limits by age
Age at year-endRegular limitCatch-upTotal
Under 50$24,500—$24,500
50–59 or 64+$24,500$8,000$32,500
60–63$24,500$11,250$35,750

Inspectable method

How the projection is built

The calculator uses official contribution mechanics for 2026 and keeps future market and limit assumptions editable. It does not fetch balances, prices or payroll records at runtime.

  1. 01

    Build the 2026 paycheck plan

    The calculator finds your age-at-year-end limit, subtracts employee deferrals already made, and caps each remaining deduction at both basic pay and remaining annual capacity.

  2. 02

    Calculate the match each pay period

    For eligible civilian FERS participants, it adds the Agency Automatic (1%) Contribution, matches the first 3% dollar for dollar, and matches the next 2% at 50 cents per dollar.

  3. 03

    Compound one transparent scenario

    The selected annual return becomes an effective pay-period rate. Existing assets grow first, then that period’s employee and agency deposits enter the account.

  4. 04

    Separate deposits from market growth

    Every result reconciles opening balance, employee deposits, automatic contributions, matching contributions and investment growth instead of presenting one opaque ending number.

Agency Automatic (1%)

Eligible FERS employees receive 1% of basic pay each pay period even when their employee contribution is zero.

Matching contribution

The first 3% is matched dollar for dollar. The next 2% is matched at 50%, producing a 4% maximum match at 5% employee contribution.

No year-end true-up

Hitting the employee cap before the last paycheck can leave later match on the table. The result flags that pacing risk.

Read the estimate correctly

Assumptions and limits

  • Annual basic pay is divided evenly across 26 or 27 pay periods; real payroll can include partial periods and pay changes.
  • TSP accounts are valued daily. This planning model compounds by pay period and places deposits at period end.
  • The retirement result is measured at the beginning of the calendar year in which the selected retirement age is reached.
  • Only 2026 contribution limits are official. Later limits grow by your assumption and are not IRS forecasts.
  • One expected return is a scenario, not a guarantee. Compare more than one return and review the today-dollar result.

Not modeled in this version

BRS and other uniformed-service rules, combat-zone tax-exempt contributions, TSP loans, withdrawals, rollovers, Roth conversions, RMDs, taxes, vesting, court orders, fund-specific forecasts, Monte Carlo probability and unusual multi-plan annual-additions cases.

CSRS and other civilian users can model employee deposits and growth by switching agency contributions off. This is a planning estimate, not financial or tax advice and not an official TSP or agency payroll calculation.

Compare current paycheck cost with qualified Roth and future Traditional tax in the separate Roth vs. Traditional TSP calculator.

Primary references

Official sources

Statute, regulation and current IRS/OPM guidance control the calculator. Payroll-office examples are used only to check whole-dollar paycheck arithmetic.

Common questions

TSP calculator FAQ

Does the FERS agency match count toward my TSP contribution limit?

No. The $24,500 elective-deferral limit and age-based catch-up limit apply to your employee Traditional and Roth contributions combined. Agency contributions are tracked separately. Unusual multi-plan or annual-additions-limit cases are outside this calculator.

Why can contributing too much per paycheck reduce my match?

The ordinary FERS match is calculated each pay period and TSP does not provide a year-end true-up. If employee contributions hit the annual cap early, later pay periods can have no employee contribution to match. The calculator shows captured and uncaptured remaining-year match under the entered pace.

Who must make 2026 catch-up contributions as Roth?

For 2026, catch-up contributions above the regular limit must be Roth when payroll determines the rule applies based on prior-year wages above $150,000. The threshold is strictly greater than $150,000. Confirm the 2026 determination with payroll rather than inferring it from salary, AGI, or a guessed W-2 field.

What investment return should I enter?

Use a planning assumption you are willing to stress-test, net of fees. No single rate predicts TSP fund performance. Try a lower and higher scenario and compare the result in today’s dollars rather than treating the default as a forecast.

Does this calculator support military BRS participants?

No. Version 1 models civilian pay periods and civilian FERS agency contributions. BRS timing, service-entry rules, special and incentive pay, combat-zone contributions and the BRS contribution cutoff require a different contract.

Are the future contribution limits official IRS limits?

No. Only the 2026 limits are authoritative here. Later limits grow by the assumption you enter so the long-range projection does not freeze contributions forever. The calculator labels those values as modeled, not predicted IRS limits.

Planning beyond the balance

See what your federal experience can earn outside government

BeyondGov translates your federal background and surfaces private-sector roles that fit. Use the TSP estimate as one input—not the whole decision—when evaluating a transition.

Explore matched roles