If you're 50 or older, earned more than $150,000 in W-2 wages last year, and have been quietly stashing extra pre-tax dollars into your 401(k) every December, 2026 just took that option away. Starting this year, the "catch-up" contributions that older, higher-earning workers rely on to close the retirement gap must go into a Roth account instead — no tax deduction, no choice, and no grace period once your plan's compliance window closes.
This isn't a proposal or a talking point from a pending bill. It's a final rule under the SECURE 2.0 Act, and it changes how business owners, key employees, and the payroll systems that serve them have to operate starting January 1, 2026.
What Actually Changed
Section 603 of SECURE 2.0 requires that catch-up contributions made by higher-earning participants in 401(k), 403(b), and governmental 457(b) plans be designated as Roth contributions — meaning they're funded with after-tax dollars and grow tax-free, rather than reducing your taxable income the way a traditional pre-tax contribution does.
The rule only applies to the catch-up portion of your contributions, not your entire deferral. For 2026:
- The standard employee deferral limit is $24,500. You can still split this however you like between pre-tax and Roth.
- The standard catch-up limit for participants 50 and older is $8,000.
- The enhanced catch-up limit for participants who turn 60, 61, 62, or 63 during the year is $11,250.
If you're subject to the mandate, that catch-up amount — the $8,000 or the $11,250 — has to go into a Roth account. Everything below the base $24,500 limit is unaffected and remains your choice.
Who Gets Pulled Into the Mandate
The trigger is straightforward on paper: you must be 50 or older by December 31 of the contribution year, and your prior-year FICA wages from that same employer must have exceeded $150,000 (a threshold that's indexed and will rise slightly in future years).
Two details trip people up:
It's measured per employer, not per household or combined income. FICA wages mean what's reported on your W-2 — Box 3 (Social Security wages, capped at the annual wage base) or Box 5 (Medicare wages, which are uncapped and typically the more relevant figure for higher earners). If you changed jobs mid-year, or your business's payroll didn't cross $150,000 with any single employer last year, you may not be caught by the mandate at all, even if your combined income is well into six figures.
It only applies to W-2 wages, not K-1 income. This is the detail that matters most for small business owners. If you're a partner in a partnership, an LLC member taxed as a partnership, or otherwise receive a K-1 rather than a W-2, the Roth catch-up mandate doesn't apply to you — SECURE 2.0's "age and wage" test is written around FICA wages, and K-1 income isn't FICA wages. But if you run your business as an S-corp and pay yourself a W-2 salary above the threshold, your own catch-up contributions to your solo 401(k) or company plan are subject to the same rule as any other employee.
The Roth-Only Trap: No Roth Option, No Catch-Up At All
Here's the part that catches plan sponsors off guard: if your 401(k) plan doesn't offer a Roth deferral option, affected participants can't make catch-up contributions in any form — not pre-tax, not Roth, not at all. The plan has to either add a Roth feature or effectively cap out higher earners at the base deferral limit once they hit the threshold.
For a small business running a solo 401(k) or a company plan through a third-party administrator (TPA), this is worth checking now rather than in December. Not every legacy 401(k) document includes Roth provisions, and adding one requires a plan amendment — most plans need to be amended by December 31, 2026 to reflect the new requirement, regardless of whether the plan runs on a calendar or fiscal year. The IRS has said good-faith compliance with the final regulations is sufficient for 2026 itself, but that grace period ends with the plan year beginning January 1, 2027.
Why This Matters More Than It Looks Like It Should
On the surface, "your catch-up contribution goes into a Roth account instead of pre-tax" sounds like a minor mechanical change. In practice, it's a meaningful tax-timing shift for the exact people the catch-up provision was designed to help.
A 55-year-old business owner who used to shelter $8,000 from this year's taxable income now pays ordinary income tax on that $8,000 up front. At a 32% marginal federal rate, that's roughly $2,560 in current-year tax that used to be deferred — money that has to come from cash flow now instead of from the account balance decades from now. The trade is that the $8,000 and all its future growth come out completely tax-free in retirement, which is a good deal if you expect to be in a similar or higher bracket later. But it's a cash-flow hit this year that a lot of owners haven't budgeted for, especially if they were counting on that deduction to offset a strong year.
If you run payroll for employees who cross the $150,000 threshold, there's an operational cost too: your payroll provider or TPA needs to correctly identify prior-year wages per employee and route catch-up elections to the right account type automatically. Getting this wrong — letting a Roth-mandated employee's catch-up land in a pre-tax bucket — creates a correction headache that plan sponsors are now expected to catch before it becomes a compliance failure.
What to Do Before Year-End
- Check your plan document for a Roth deferral feature. If you sponsor a solo 401(k) or a small company plan and it's pre-tax only, talk to your TPA or plan provider about amending it before the compliance deadline.
- Pull last year's W-2 Box 5 wages for yourself and any employees over 50. That's the number that determines who's affected for 2026 contributions — not your projected income for this year.
- Separate W-2 owners from K-1 partners in your compliance check. S-corp owner-employees are in scope; partnership and LLC partners generally aren't, based on how they're paid.
- Model the cash-flow impact. If you or a key employee are affected, budget for paying tax on the catch-up amount this year rather than deferring it — the deduction you were counting on isn't there anymore.
- Confirm with your payroll provider that they can flag affected employees and split catch-up contributions to a Roth source automatically, rather than relying on manual tracking.
Keep Your Retirement and Payroll Records Straight
Rules like this one turn on a single number — last year's W-2 wages from one employer — so the accuracy of your payroll and compensation records matters more than usual. Beancount.io gives you plain-text accounting you can query and audit directly: wage totals, employer contributions, and retirement plan activity all live in version-controlled files instead of a black-box payroll dashboard, so you can verify exactly which threshold you crossed and when. Get started for free and keep the numbers that drive decisions like this one fully in your control.