How much should I contribute to the TSP?

At least 5 percent of basic pay to capture the full agency match under BRS or FERS. Beyond that, contribute as much as your budget allows up to the 2026 limit of $24,500, prioritizing tax-advantaged accounts before taxable investing.

What is the 2026 TSP contribution limit?

The elective deferral limit is $24,500 for 2026. Servicemembers 50 and older can add an $8,000 catch-up contribution. Agency matching contributions do not count against your limit.

Should I choose Roth or traditional TSP?

Roth is often better for junior servicemembers in low tax brackets, and especially powerful for contributions from tax-free combat zone pay, which are never taxed. Traditional wins if you expect a higher tax rate now than in retirement.

What happens to my TSP when I separate?

It stays yours, including matched money once vested (2 years under BRS). You can leave it invested, roll it to a civilian 401(k) or IRA, or withdraw with taxes and possible early-withdrawal penalties.

Is the 5 percent match really free money?

Effectively yes: contribute 5 percent and the government adds 5 percent of your basic pay (1 percent automatic plus 4 percent match). Contributing less leaves part of it unclaimed every pay period.

Can I max out the TSP on military pay?

Junior enlisted may find $24,500 a stretch, but senior NCOs and officers often can, especially by contributing from bonuses and special pays. Even partial progress toward the limit compounds powerfully over a career.

What are the TSP investment options?

Five core funds (G government securities, F bonds, C large US stocks, S small US stocks, I international stocks) plus Lifecycle L funds that auto-rebalance toward a target date. Expense ratios are around 0.05 percent.

TSP Calculator: Contribution Growth Projector

Project your Thrift Savings Plan balance with 2026 contribution limits, agency matching under BRS/FERS, and compound growth over your career.

How TSP matching works

The Thrift Savings Plan is the federal 401(k)-style retirement account, and under BRS and FERS the government puts money in alongside you. You get an automatic 1 percent of basic pay whether you contribute or not, plus matching contributions up to 4 percent: dollar for dollar on the first 3 percent you contribute, and 50 cents on the dollar for the next 2 percent. Contribute at least 5 percent and the agency total is 5 percent of your salary, which is why every briefing says the same thing: contribute 5 percent minimum or leave free money behind.

2026 contribution limits

The 2026 elective deferral limit is $24,500, the most you can contribute from your own pay in a year. Servicemembers age 50 and older get an additional $8,000 catch-up contribution, for a $32,500 total. This calculator caps your annual contribution at $24,500 and flags it when the cap binds, because anything above the limit simply cannot go in. Note that the limit applies to your contributions only; agency matching does not count against it.

Future value = P x (1 + r)^n + C x (((1 + r)^n - 1) / r)
where P = current balance, C = annual contribution (yours + agency match), r = annual return, n = years

Roth vs traditional TSP

Traditional contributions reduce your taxable income now and are taxed on withdrawal. Roth contributions are taxed now and grow tax free. For servicemembers the Roth option is often unusually attractive: if you contribute while deployed to a combat zone, that pay is already tax free, so Roth contributions made from it are never taxed at all, going in or coming out. The Roth share field above is informational; it does not change the projected balance, but it changes how much of that balance is yours after taxes.

Worked example

A servicemember with a $10,000 balance, $60,000 basic pay, contributing 5 percent with agency matching, over 20 years at 7 percent annual return:

Your contribution: 5% x $60,000 = $3,000/year (well under the $24,500 limit)
Agency match: 1% automatic + 4% match = $3,000/year
Total annual investment: $6,000
Projected balance: about $284,670

Half of every annual investment came from the match. Over 20 years the agency contributed $60,000 of the $120,000 total invested, and compounding did the rest. Skip the match and the same career ends near $154,000 instead: that gap is the cost of contributing less than 5 percent.

How this is calculated: your annual contribution is your salary times your contribution percent, capped at the 2026 elective deferral limit of $24,500 (the calculator flags when the cap binds). Agency matching is computed as 1 percent automatic plus dollar-for-dollar matching on the first 3 percent and 50 cents on the dollar for the next 2 percent, totaling 5 percent of salary at a 5 percent contribution. Growth uses annual compounding at your assumed return on the starting balance plus yearly contributions. Taxes, fees, and inflation are not modeled.

Which funds to use

The TSP offers five core funds (G, F, C, S, I) and Lifecycle (L) target-date funds that rebalance automatically. Expense ratios run around 0.05 percent, among the lowest anywhere. Young servicemembers with decades ahead often hold mostly C and S (US stocks) or simply pick the L fund matching their expected retirement year. The return assumption you enter above matters more than fund-picking precision: 7 percent is a common planning figure for a stock-heavy portfolio, not a promise.

What happens at separation

Your TSP is yours when you leave service, including the matched money once vested (BRS matching vests after 2 years). You can leave it invested, roll it into a civilian 401(k) or IRA, or withdraw it (with taxes and possible penalties before age 59 and a half). Leaving it alone in the low-cost TSP is often the best option nobody tells you about.