Mandatory Roth Catch-Up Calculator 2026
Check whether SECURE Act 2.0 §603 forces your 401(k) catch-up contributions to be Roth instead of pre-tax for 2026. The rule applies if your prior-year FICA wages from the plan sponsor exceed $145,000 (indexed). Original effective date was 2024 but IRS deferred to 2026. Free — runs in your browser.
What SECURE Act 2.0 §603 Requires
Section 603 of the SECURE Act 2.0 (December 2022) requires that catch-up contributions to 401(k), 403(b), and governmental 457(b) plans be made on a Roth (after-tax) basis if the participant\'s FICA wages from the plan sponsor in the prior calendar year exceeded $145,000 (indexed for inflation). The threshold is $145,000 for 2024, $145,000 for 2025 (announced; OBBB did not modify), and is projected to reach approximately $150,000 for 2026 pending IRS confirmation. Originally effective for tax year 2024, the IRS provided a two-year administrative transition period in Notice 2023-62, deferring the requirement to 2026. The 2025 catch-up limit (age 50+) is $7,500; the 2026 limit is expected to remain $7,500 (indexed). SECURE 2.0 §109 also created a higher "super catch-up" of $11,250 for ages 60-63 starting 2025. Source: IRS Notice 2023-62.
How the FICA Wage Test Works
The test looks at FICA wages (Social Security and Medicare-taxable wages, Box 3/5 of the W-2) paid by the SAME employer sponsoring the plan in the prior calendar year. If you change jobs mid-year, the new employer\'s test resets — your prior-year wages with that new employer (typically zero in your first calendar year there) are below the threshold, exempting you. Self-employed individuals with no FICA wages from a 401(k) sponsor are exempt from §603 because they have no FICA wages from a plan sponsor — only earned income from self-employment. Government employees and church plan participants may have different applicable thresholds. The threshold is plan-by-plan, not aggregated — if you work for two employers each below $145,000 in FICA wages individually, neither plan\'s catch-up is forced to Roth even if combined wages exceed the threshold. Source: IRC §414(v)(7) (Cornell).
Tax Impact: Roth Catch-Up vs Pre-Tax Catch-Up
A $7,500 Roth catch-up contribution does not reduce current-year taxable income, costing approximately $2,400 more in federal tax for a worker in the 32% bracket. The benefit: tax-free growth and tax-free distributions in retirement, including no RMDs from Roth 401(k) starting 2024 (SECURE 2.0 §325). For high earners expecting their retirement bracket to be lower (early retirement, geographic move to no-income-tax state), pre-tax was typically better — losing this option costs real money. For high earners expecting their retirement bracket to be similar or higher (large traditional balances driving RMDs into 32%+ brackets in late 70s), the mandatory Roth catch-up is actually a benefit, locking in tax-free dollars. Source: IRS Cost-of-Living Adjustments for Retirement Items.
Workarounds for High Earners
If your plan does not yet offer a Roth 401(k) feature, the plan must add one before 2026 or you cannot make catch-up contributions at all under §603. Some plans may delay catch-up implementation until plan amendment is complete — verify with your plan sponsor. Alternative strategies for affected high earners: (1) Switch employers so the prior-year FICA wages with the new employer are below the threshold in your first year. (2) Make catch-up contributions in your spouse\'s 401(k) if their wages are below the threshold. (3) Consider after-tax 401(k) "mega backdoor Roth" contributions — separate from catch-up and not subject to §603. (4) For very high earners hitting the §415(c) total contribution limit of $70,000 (2025), the catch-up amount is on top — see our Mega Backdoor Roth Calculator. Last updated May 2026.
Frequently Asked Questions
What is SECURE Act 2.0 §603?
Section 603 of the SECURE Act 2.0 (December 2022) requires that 401(k), 403(b), and governmental 457(b) catch-up contributions be Roth (after-tax) for high earners whose prior-year FICA wages from the plan sponsor exceeded $145,000 (indexed). Originally effective for tax year 2024 but IRS Notice 2023-62 deferred implementation to tax year 2026.
Who counts as a "high earner" for §603?
Anyone whose FICA wages (Social Security + Medicare wages, W-2 Box 3 or 5) from the plan-sponsoring employer in the immediately prior calendar year exceeded $145,000. The threshold is indexed for inflation under §414(v)(7)(A) — projected at approximately $150,000 for 2026. The test is at the plan-sponsor level — wages from other employers are not aggregated for this purpose.
What if I switched employers mid-year?
The test uses prior-year FICA wages with the SAME employer. If you started with a new employer in 2025, your 2025 prior-year wages from them are zero (you were not employed in 2024), so §603 does not apply for 2025. Once you have a full prior year of FICA wages with the employer, the test applies if those wages exceed $145,000.
Does §603 apply to self-employed Solo 401(k) holders?
No. Self-employed individuals have no FICA wages from a plan sponsor — they have net self-employment earnings under §1402, which are not "wages" under FICA Title II. §603 explicitly references "wages from the employer" and §414(v)(7) limits this to FICA wages. Solo 401(k) participants remain free to choose pre-tax or Roth catch-up regardless of income level.
What is the 2026 catch-up contribution limit?
For ages 50+, the standard 401(k) catch-up limit is projected at $7,500 for 2026 (subject to IRS inflation adjustment; was $7,500 in 2024 and 2025). For ages 60-63, SECURE Act 2.0 §109 created a higher "super catch-up" limit at the greater of $10,000 or 150% of the standard catch-up — projected at $11,250 for 2026 (was $11,250 for 2025). The super catch-up applies only in calendar years you are 60, 61, 62, or 63 — at age 64 it reverts to the standard $7,500.
What if my plan does not offer a Roth 401(k) option?
If your plan lacks a Roth 401(k) feature and you exceed the §603 threshold, you cannot make catch-up contributions at all starting 2026 — until the plan adds Roth functionality. Most plan sponsors are adding Roth features in 2024-2025 to accommodate §603. Verify with your HR/benefits team before year-end. Note: §603 applies to designated Roth accounts inside the 401(k), not to backdoor Roth IRA contributions outside the plan.
Did the OBBB change the §603 threshold?
No. The One Big Beautiful Bill Act (P.L. 119-21, July 2025) extended TCJA-era individual rates and made the §199A QBI deduction permanent, but did not alter SECURE 2.0 §603. The §603 effective date remains 2026 per IRS Notice 2023-62 (the 2-year administrative transition). The $145,000 threshold is indexed for inflation under §414(v)(7)(A).