For workers age 50 and older, 2026 brings a new wrinkle to 401(k) catch-up contributions. If you earned more than $150,000 in 2025 from the employer sponsoring your plan, your 2026 catch-up contributions generally must go into the Roth side of the plan, assuming the plan offers catch-up contributions and a Roth feature.
That sounds simple until payroll enters the picture. The rule does not use your household income, tax-return income, or even necessarily the salary number that appears most prominently on your pay stub. It looks at a specific type of prior-year wages from the same employer, which creates plenty of room for confusion when compensation changes, employers merge, workers switch jobs, or payroll records contain mistakes.
The $150,000 Figure Has a Surprisingly Specific Meaning
The first thing to check is where that $150,000 came from. For 2026, the IRS uses your 2025 FICA wages from the employer sponsoring your retirement plan, and the threshold applies when those wages exceeded $150,000.
That means a household earning $200,000 does not automatically trigger the rule. Likewise, someone with a large amount of income from investments does not trigger it based on that investment income. The relevant test focuses on wages from the plan sponsor, so the number on a tax return can tell a different story from the number that controls this particular retirement rule.
There is another wrinkle for workers who changed jobs. The rule generally looks at wages from the employer sponsoring the plan, rather than combining every paycheck from every company during 2025.
Your Regular 401(k) Money Does Not Suddenly Become Roth
The new rule targets catch-up contributions, not every dollar you put into the 401(k). For 2026, the regular employee elective deferral limit for most 401(k) plans is $24,500, while the standard catch-up limit rises to $8,000.
Someone age 50 or older could therefore generally contribute as much as $32,500 through regular and catch-up contributions in 2026, assuming the plan permits the full amounts. Workers who turn 60, 61, 62, or 63 during 2026 can have a higher catch-up limit of $11,250 instead.
For a high earner subject to the Roth requirement, the regular $24,500 does not automatically need Roth treatment. The special requirement applies to the catch-up portion. That distinction matters because a worker can still have both traditional pre-tax and Roth contributions flowing from the same paycheck.
Payroll Has to Identify the Right Wages Before the Catch-Up Starts
This is where a seemingly ordinary payroll setting can become a retirement-planning headache. The system needs to determine whether your 2025 wages from the plan sponsor exceeded the applicable threshold, then apply the Roth requirement to 2026 catch-up contributions.
The IRS regulations specifically address how plans can handle these calculations and correct pre-tax contributions that should have received Roth treatment. They also allow certain plans to use a deemed Roth election, which can automatically treat required catch-up contributions as Roth unless the worker makes a different permitted election.
That does not mean every payroll department will make an error. It does mean workers have a reason to inspect their elections rather than assuming the payroll system has everything perfectly sorted. A promotion, bonus, acquisition, corrected W-2, or job transfer can create circumstances that deserve a closer look.
The Pay Stub Number May Not Answer the Question
A common mistake involves comparing the $150,000 threshold with the wrong income figure. The IRS rule uses wages under the FICA definition, which makes this a more specific measurement than simply looking at adjusted gross income or taxable income.
For example, a worker might see one wage figure on a tax document and assume that number determines Roth catch-up treatment. Payroll and retirement-plan records can involve different wage definitions, however, so the right question involves the wages used for the statutory test. The IRS also specifically discusses situations in which an amended W-2 changes whether someone falls above the threshold.
Workers should check whether their 2025 employer-reported wages crossed $150,000, especially if compensation included bonuses or other variable pay. If the number looks wrong, contacting the employer’s payroll or benefits team can help resolve the discrepancy before the year gets too far along.
A Roth Catch-Up Changes the Tax Timing, Not the Contribution Opportunity
Roth 401(k) contributions do not receive the same upfront tax treatment as traditional pre-tax contributions. The Roth amount generally enters taxable income when contributed, while qualified Roth distributions can come out tax-free under applicable rules.
That difference can make a bigger dent in a paycheck for someone accustomed to putting catch-up dollars into a traditional 401(k). The contribution itself has not disappeared, though. Instead, the tax treatment has changed for catch-up dollars subject to the new requirement.
The change also makes the paycheck worth examining before the first few months of 2026 disappear. A worker who expected a traditional catch-up deduction might see a different tax withholding result once those dollars move into Roth. The retirement account can still receive the contribution, but the tax bill gets handled on a different schedule.
Check the Election Before the Year Gets Away from You
The 2026 rule turns a familiar retirement habit into something that deserves a quick annual audit. Start with the 2025 wages from the employer sponsoring the 401(k), confirm whether they exceeded $150,000, and then check how the plan handles Roth catch-up contributions.
Also check the contribution totals during the year. Catch-up contributions do not begin simply because someone turns 50, and they only count after applicable regular deferral limits or other plan limits are reached.
If the payroll election appears inconsistent with the plan’s rules, ask the benefits or payroll department how the system determines Roth catch-up eligibility. The IRS has established correction methods for certain failures, so a payroll mistake does not necessarily mean the money is permanently stuck in the wrong tax bucket.
The New Rule Makes One Old Habit Worth Retiring
For years, checking a 401(k) contribution percentage could feel like a set-it-and-forget-it task. The Roth catch-up requirement makes that approach less reliable for some higher-paid workers because a prior year’s wages can affect how current-year catch-up contributions receive tax treatment.
For anyone near the threshold, a few minutes spent checking the wage figure and payroll election could prevent a much more annoying cleanup later. Retirement contributions involve enough moving parts already, so there is little benefit in letting a software setting become the boss of the tax treatment.
Do you think your employer’s payroll system will handle the new Roth catch-up rule correctly, or will workers need to keep a closer eye on their 401(k) elections?
You May Also Like…
Retirement Limits That Changed in 2026 That Savers Still Have Time to Use
You Have $2 Million Saved. What Could Still Derail Your Retirement?
The IRS Just Eased 401(k)-to-IRA Rollovers — But One Missed Step Still Costs You 20% Upfront
You’re Maxing Out Your 401(k) but Have No Emergency Fund. Is That Backwards?
Should You Pay $25,000 in Taxes Today to Avoid a Bigger Tax Bill in Retirement?
Brandon Marcus is a writer who has been sharing the written word since a very young age. His interests include sports, history, pop culture, and so much more. When he isn’t writing, he spends his time jogging, drinking coffee, or attempting to read a long book he may never complete.
