The annual limit on elective deferrals

What counts against the limit, and what does not

The limit is on your money, not your employer's.

• Counts: your traditional (pre-tax) TSP contributions and your Roth (after-tax) TSP contributions, added together.
• Does not count: Agency or Service Automatic (1%) Contributions. That is your employer's money, not your pay.
• Does not count: Agency or Service Matching Contributions. Same reason.
• Does not count: traditional contributions made from tax-exempt pay you earned in a designated combat zone. See the combat zone card below — there is a catch to it.
• Does not count against this year: makeup contributions your agency or service failed to make in a prior year. Those go against the limit for the year they should have been made.

It follows you, not your job

One person, one limit — no matter how many plans you are in.

• If you have a civilian TSP account and a uniformed services TSP account, the limit applies to the total you put into both. Same for catch-up contributions.
• If you are in the TSP and another employer's plan — a private-sector 401(k), a 403(b), a 408(k) or a 501(c)(18) — the limit applies to the combined total of everything you deferred that year. This is the Guard and Reserve situation, and it is the situation of anyone who just separated and took a civilian job.

Front-loading costs you the match

Matching is figured pay period by pay period. Not once a year.

• You are matched on the first 5% of basic pay you contribute each pay period. The first 3% is matched dollar for dollar and the next 2% at fifty cents on the dollar — so contributing 5% earns you a 4% match.
• If you are under 50 and you hit the annual limit early, your contributions stop for the rest of the year, and your match stops with them. That match cannot be made up. TSP's own words: what you lose in matching can be far greater than what you gain by contributing sooner.
• If you turn 50 or older during the year, your contributions do not stop at the elective deferral limit. They spill over toward the catch-up limit automatically, and matching keeps coming on the first 5% of pay until the catch-up limit is reached too.

Catch-up contributions, and the part most people get wrong

Catch-up money is extra, and for FERS and BRS it is matched.

• You are eligible if you are age 50 or older by the end of the calendar year. Turn 50 on December 31 and you are eligible for the whole amount for that entire year.
• Catch-up has its own separate annual limit. It does not count against the elective deferral limit or the annual additions limit.
• Catch-up contributions are matched. If you are FERS (the Federal Employees Retirement System) or BRS (the military's Blended Retirement System), your contributions toward the catch-up limit are eligible for matching on the first 5% of your pay, same as the rest. Most people believe catch-up money is unmatched. It is not, and believing it leaves agency money behind.
• In the years you turn 60, 61, 62 or 63, the catch-up limit is higher — $11,250 for 2026, against $8,000 for ages 50–59. In the year you turn 64 it drops back to the regular amount.
• You do not have to start a separate election. Once your contributions reach the elective deferral limit, additional contributions automatically count toward the catch-up limit.

The Roth catch-up rule, and who it actually hits

It is measured narrower than people think.

• As of January 1, 2026, if your prior-year wages exceeded the IRS threshold, all of your catch-up contributions must be Roth (after-tax), no matter what you elected. For 2026 the threshold is wages of more than $150,000 in 2025. It is adjusted for inflation each year.
• Read the measure carefully. It is prior-year FICA wages — the wages Social Security and Medicare tax is taken from — paid by the employer that sponsors the plan. Not household income. Not adjusted gross income. Not wages from some other job.
• So a veteran who starts a federal job partway through the year, with no prior-year wages from that employer, is not caught by this rule at all.
• If the rule does apply to you, nothing breaks. Once your traditional contributions reach the elective deferral limit, the additional money automatically becomes catch-up and lands in the Roth balance of your account.

Deployed pay has its own rules

This is where a deployed Soldier can put away far more than the limit — and where a wrong election blows it.

• Traditional contributions made from tax-exempt pay earned in a designated combat zone do not count toward the elective deferral limit.
• Roth contributions from combat-zone pay DO count toward the elective deferral limit, in full. The exemption is for traditional money only. Read "combat-zone pay doesn't count" too broadly, elect Roth while deployed, and you can run past the limit and lose match without ever knowing it.
• For catch-up contributions while you are receiving tax-exempt pay, only Roth is allowed. The TSP cannot accept traditional tax-exempt contributions toward the catch-up limit.

Not everybody does, and the page nobody reads says so

• CSRS employees (the older Civil Service Retirement System) receive no Automatic (1%) and no matching contributions.
• Uniformed services members not covered by BRS — the legacy retirement system — receive no Automatic (1%) and no matching either. If that is you, contributing 5% does not produce a 4% match, and you should not plan around one.
• BRS members who entered service on or after January 1, 2018: Automatic (1%) Contributions begin after 60 days of service, and matching does not begin until after two years of service. A junior Soldier contributing 5% in year one is not yet getting the match.
• Vesting. BRS members must complete two years of service to keep the Automatic (1%) money. Separate before that and the unvested 1% is forfeited. Your own contributions and their earnings are always yours.

If you went over: March 15, not April 15

This is the one that costs real money, and the date most people have wrong.

• Can't find the form? It is released for a limited window each January. If it is not in My Account, do not assume you missed your chance — call the ThriftLine and ask.
• ThriftLine: 1-877-968-3778, toll free, Monday through Friday, 7:00 a.m. to 9:00 p.m. eastern time. From outside the United States, (404) 233-4400 — not toll free. Hearing or speech disabilities: 711 TTS Relay, free.
• The other plan has its own clock. The tax code sets March 1 as the date by which you allocate the excess among your plans and notify them, and any plan may set an earlier date of its own. March 15 is TSP's date. If the refund has to come out of a private 401(k) or 403(b), call that plan in January. Do not assume they will take a March 15 request.
• April 15 does not move. A tax filing extension does nothing for it. There is no extension mechanism for this deadline.

What happens if the excess stays in

• Excess deferrals are income in the year you made them, refunded or not. Each employer reports your deferred income in Box 12 of your W-2. Roth excess is already in Box 1 as wages.
• If you take the refund you get a Form 1099-R showing it, and the IRS gets a copy. If you already filed without counting it as wages, you file an amended return.
• Earnings paid out with the excess are taxable in the year they are distributed — that is different from the excess itself. Roth earnings paid out this way are taxable even if you already meet the Roth qualified-distribution test.
• Refunded by April 15, it is not treated as an early withdrawal and there is no IRS early-withdrawal penalty.
• Not out by April 15: you can no longer request a refund. A traditional excess stays in the account and gets taxed twice — once in the year of the excess, and again when you separate and withdraw it. Take it out early and you may draw the early-withdrawal penalty on top. A Roth excess loses its after-tax treatment, the double-taxation rule applies, and you owe tax on the earnings even if you otherwise qualify. Earnings themselves are taxed once, at withdrawal.
• The match tied to the excess comes out too. Your agency or service is required to remove the matching contributions associated with the returned excess. You do not get that back by contributing more later in a year you have already maxed.

Two small things that cost people money

• Under 50 and you hit the limit: your contributions stop automatically. The TSP will not process anything over the limit. Your payroll office is responsible for restarting your contributions with the first pay date of the following year — check your first January leave and earnings statement and make sure they did.
• Where the real numbers live: TSP's fact sheet deliberately prints no limit, because it changes every January. The figures in this binder are the 2026 figures. Confirm at tsp.gov/making-contributions/contribution-limits or on the catch-up page at tsp.gov/catch-up before you set an election.