TSP Roth Catch-Up: 3 Critical Rules to Avoid a 2026 Tax Penalty

The short answer: A new TSP Roth catch-up rule takes effect January 1, 2026. Federal employees who are age 50 or older and earned more than $150,000 in FICA wages in 2025 can no longer make traditional catch-up contributions. Any catch-up amounts must now go into Roth.

This change affects a specific group of higher-earning federal employees who are approaching retirement. The rule comes from Section 603 of the SECURE 2.0 Act, and the Thrift Savings Plan began applying it this year. Below is a plain-language look at who is affected, how the TSP handles it, and what the 2026 numbers look like.

• The TSP Roth catch-up requirement applies to participants who earned more than $150,000 in FICA wages from their employer in 2025 and are age 50 or older in 2026 (TSP.gov).
• The 2026 elective deferral limit is $24,500, up from $23,500 in 2025 (IRS IR-2025-111).
• The standard catch-up limit for ages 50–59 and 64 and over is $8,000 in 2026 (TSP Bulletin 25-3).
• A higher catch-up limit of $11,250 applies to participants who turn 60, 61, 62, or 63 in 2026 (TSP Bulletin 25-3).
• The TSP uses the spillover method, so catch-up amounts switch to Roth automatically for most affected participants once the deferral limit is reached (TSP.gov).

What is the TSP Roth catch-up rule for 2026?

The TSP Roth catch-up rule requires certain higher earners to make their catch-up contributions as Roth instead of traditional. It started January 1, 2026. The change comes from Section 603 of the SECURE 2.0 Act of 2022.

Before this rule, federal employees could choose traditional (pre-tax) or Roth (after-tax) for catch-up contributions. Now, for affected participants, that choice is removed for the catch-up portion. According to the TSP, Section 603 requires catch-up contributions to be Roth once a covered participant reaches the pre-tax maximum.

Who is affected by the new catch-up rule?

The rule applies to participants who meet two conditions at the same time. Both conditions must be true.

• You earned more than $150,000 in FICA wages from your employer in 2025.
• You are age 50 or older during 2026.

The $150,000 figure is the income threshold for 2026, and the TSP notes it is adjusted for inflation in future years. The original SECURE 2.0 threshold was $145,000, and it has since risen to $150,000.

If your 2025 wages were $150,000 or less, the rule does not change anything for you. You can keep making catch-up contributions according to your current election. The rule also does not apply if you are in a position that is not TSP eligible.

Does the rule use total pay or a specific wage figure?

The threshold is based on FICA wages, not total compensation. FICA wages are the amount reported for Social Security and Medicare tax purposes. This figure may differ from your salary or your gross pay, so the precise number on your earnings record is what matters here.

How does the TSP Roth catch-up actually work through payroll?

The TSP uses the spillover method, so the change happens automatically for most people. You do not file a separate catch-up election. Once your contributions exceed the elective deferral limit, extra amounts spill over toward the catch-up limit.

For affected higher earners, those spillover amounts are directed to Roth once the traditional pre-tax maximum of $24,500 is reached. The TSP states that this switch happens automatically for most participants. Some may need to confirm with their payroll office that contributions are designated correctly.

One detail often overlooked: if you do not already have a Roth TSP balance, your first Roth catch-up contribution will create one. That can be a new account feature for long-time traditional-only savers.

What if someone does not want to make Roth catch-up contributions?

Participants who prefer not to contribute Roth catch-up amounts have one option. According to the TSP, they can adjust their TSP contributions to avoid exceeding the elective deferral limit. Doing so means forgoing catch-up contributions for that year. This is a personal trade-off that some federal employees weigh against the tax treatment of Roth savings.

What are the 2026 catch-up limits by age?

The catch-up limit depends on your age during the year. The 2026 figures are set by the IRS and applied by the TSP.

• Ages 50–59 and 64 and over: $8,000 standard catch-up limit.
• Ages 60, 61, 62, and 63: $11,250 higher catch-up limit.

The higher limit for ages 60–63 comes from Section 109 of SECURE 2.0. Federal employees in that age band who are also over the income threshold would see their catch-up contributions, up to $11,250, treated as Roth. For a closer look at that age-specific limit, see our guide to the TSP super catch-up contributions for ages 60–63.

Combined with the $24,500 elective deferral limit, a participant aged 60–63 could contribute up to $35,750 across regular and catch-up amounts in 2026. The IRS confirms that participants 50 and older can generally contribute up to $32,500 with the standard catch-up.

Why did the catch-up rule change for higher earners?

The change traces back to the SECURE 2.0 Act, signed into law in 2022. Section 603 directed that catch-up contributions for higher earners be made on a Roth basis. The provision was originally set for an earlier date, then delayed, and now applies starting in 2026.

Roth contributions are made with after-tax dollars. The trade-off is that qualified Roth withdrawals in retirement can be tax free. For higher earners, this shift changes the timing of when taxes are paid on the catch-up portion. Planning around this often involves looking at your full retirement picture, including pensions, Social Security, and other accounts.

How does this connect to other TSP decisions near retirement?

The Roth catch-up rule is one of several TSP details that can surface as retirement approaches. Contribution rules, withdrawal rules, and beneficiary records all interact over time.

For example, spousal rights can affect how withdrawals are handled, a topic covered in our overview of TSP spousal consent withdrawal rules. Keeping your account records current also matters, which is why some federal employees review their TSP beneficiary designations at the same time. These are separate from the catch-up rule, but they often come up together when people plan ahead.

Frequently asked questions

Who has to make the TSP Roth catch-up in 2026?

The TSP Roth catch-up applies to participants who earned more than $150,000 in FICA wages in 2025 and are age 50 or older in 2026. Both conditions must be met. Those at or below the threshold are not affected.

Is the $150,000 threshold based on 2025 or 2026 income?

It is based on prior-year FICA wages, meaning 2025 wages determine the rule for 2026. The threshold is indexed for inflation, so the figure can change in later years.

Do I need to do anything to switch my catch-up to Roth?

For most participants, the switch is automatic through the TSP spillover method. Some may need to confirm with their payroll office that contributions are coded as Roth. If you had no Roth balance before, the first Roth catch-up contribution creates one.

What happens if I do not want Roth catch-up contributions?

According to the TSP, you can adjust your contributions to stay at or below the elective deferral limit. That avoids the catch-up entirely for the year. It also means missing the additional catch-up savings, so it is a trade-off some people weigh carefully.

Does the rule change the dollar limits I can contribute?

No. The catch-up limits are still $8,000 for ages 50–59 and 64 and over, and $11,250 for ages 60–63 in 2026. The rule changes the tax type of the catch-up portion for affected higher earners, not the amount.

Where can I confirm these figures myself?

The 2026 limits appear in TSP Bulletin 25-3 and IRS news release IR-2025-111. The income threshold and Roth requirement are described on the TSP contribution limits page. These primary sources are linked throughout this article.

Want to understand how the TSP Roth catch-up rule fits into your own retirement timeline? Fed Pilot offers free workshops built for federal employees navigating these decisions. Register for a free workshop to bring your questions and learn alongside others preparing for retirement.