To max out your 401(k) in 2026 without going over the limit, divide $24,500 by your number of pay periods, add any catch-up amount you qualify for, pace your contributions evenly across the year so you don’t lose employer matching, and track your own year-to-date total if you’ve contributed to any other plan. The IRS cap is personal to you, not to your employer, and no payroll system will stop you from exceeding it on its own.
The 2026 Limit You’re Aiming At
The elective deferral cap for 2026 is $24,500 for employees under age 50.1Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500 That ceiling covers your pre-tax traditional deferrals and your Roth 401(k) contributions combined; how you split them doesn’t change the total you’re allowed.2Internal Revenue Service. Roth Comparison Chartp>
If you turn 50 at any point during 2026, you get an additional $8,000 in catch-up room, bringing your personal ceiling to $32,500. You don’t have to wait until your birthday — the IRS treats you as 50 for the whole calendar year.3Internal Revenue Service. Issue Snapshot – 401(k) Plan Catch-Up Contribution Eligibility If you’re 60, 61, 62, or 63 during the year, SECURE 2.0 gives you an enhanced catch-up of $11,250 instead, for a personal ceiling of $35,750.1Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500 That larger catch-up disappears at 64, when you revert to $8,000.
One boundary worth knowing: the deferral limit is separate from the overall $72,000 cap on everything that goes into your account, including employer match and profit-sharing.4Internal Revenue Service. 2026 Amounts Relating to Retirement Plans and IRAs For most employees, your personal deferral is the only number you can control, and it’s the one you need to pace.
Turning the Limit Into a Per-Paycheck Number
The core math is just the annual limit divided by your pay periods. On a biweekly schedule with 26 checks, $24,500 ÷ 26 = $942.31 per paycheck. On a semi-monthly schedule with 24 checks, it’s $1,020.83. If you qualify for the standard catch-up, use $32,500 ($1,250.00 biweekly). For the 60-to-63 enhanced catch-up, use $35,750 ($1,375.00 biweekly).
Many payroll systems only take a percentage, not a dollar amount. Divide your per-check target by your gross pay for that period. Someone earning $6,000 biweekly who needs to defer $942.31 would set roughly 15.7 percent. Any time your pay changes — a raise, a bonus check, reduced hours — the percentage that was right in January will stop landing on the right dollar amount. Recheck the math after any compensation change.
Starting or Adjusting Mid-Year
If you’re setting a new rate partway through the year, subtract what you’ve already contributed from your annual limit and divide by the pay periods you have left. Contributed $10,000 through June with 13 biweekly checks remaining? ($24,500 − $10,000) ÷ 13 = $1,115.38 per check. The same subtraction works when you catch a rate that was set too low back in January.
Pace Evenly or You’ll Lose Match
This is the most expensive mistake people make trying to hit the limit. Set an aggressive deferral rate, finish contributing by September, and your deferrals drop to zero for the rest of the year. Most employers calculate matching on each paycheck, so when your deferrals stop, so does the match.
Say your employer matches 50 percent of your contributions up to 6 percent of salary. Max out by September and your employer stops matching in October, November, and December. Three months of free money, gone.
Some plans correct this with a “true-up” at year-end, comparing what you actually received in match against what you’d have received with even pacing and depositing the difference. Not every plan has one. Check your summary plan description or ask your benefits team before you decide to front-load. If there’s no true-up, pace your contributions so your final paycheck of the year — not a check in September — is the one that puts you at the limit.
If You Changed Jobs or Have More Than One Plan
The $24,500 cap follows you, not your employer.5Internal Revenue Service. How Much Salary Can You Defer if You’re Eligible for More Than One Retirement Plan? Your new employer’s payroll system has no visibility into what you contributed at the old one, so it will happily let you contribute another full $24,500. Preventing an overage is on you.
Before your first paycheck at the new job, pull the year-to-date contribution figure from your former employer’s final pay stub or plan portal. Subtract that from $24,500 (or your catch-up limit). Divide the remainder by the pay periods left at the new job. That’s your per-check deferral.
The aggregation rule also applies if you hold two jobs at once or participate in both a 401(k) and a 403(b). All elective deferrals across those plans share one limit. A governmental 457(b) is the exception; it has its own separate deferral limit.
When Your Plan Caps You Below the IRS Limit
Some high earners find they can’t contribute the full $24,500 even if the math is perfect. If you earned more than $160,000 from your employer in the prior year, you’re a highly compensated employee for nondiscrimination testing.4Internal Revenue Service. 2026 Amounts Relating to Retirement Plans and IRAs If lower-paid employees in the plan don’t contribute enough relative to higher-paid ones, the plan fails its test and restricts how much higher earners can defer.6Internal Revenue Service. Retirement Topics – 401(k) and Profit-Sharing Plan Contribution Limits
If this affects you, your plan will typically send a notice with your restricted amount. There isn’t an individual workaround; the cap reflects overall plan participation. Some employers use safe harbor plan designs that avoid nondiscrimination testing and remove this restriction.
Submitting the Election and Verifying the Check
Enter your dollar amount or percentage through your employer’s benefits portal or HR system, usually in a section labeled “Retirement Elections” or “Benefits.” Expect the change to take one or two pay cycles to show up, because payroll processing starts several days before funds are distributed.
When the first adjusted paycheck arrives, compare the 401(k) line against your target. A small mismatch usually means the system rounded your percentage, or the change didn’t make it in by the cutoff. Fix it with your benefits administrator immediately; a small per-check error compounds across the rest of the year.
Set a reminder in mid-November to review your year-to-date total and make a final adjustment. If you’re running short of $24,500, a small increase on your last one or two checks closes the gap. Give payroll enough lead time; don’t wait until the final business day of December.
If You Go Over Anyway
Excess deferrals get taxed twice if you do nothing: once in the year you contributed, and again when you withdraw them.7Internal Revenue Service. Consequences to a Participant Who Makes Excess Deferrals to a 401(k) Plan You can avoid that by requesting a corrective distribution before April 15 of the following year. For a 2026 overage, the deadline is April 15, 2027, and a tax extension does not move it.8Internal Revenue Service. 401(k) Plan Fix-It Guide – Elective Deferrals Weren’t Limited
Notify your plan administrator in writing that you’ve exceeded the limit and ask for a return of the excess plus any earnings on it. The excess is taxable in 2026; the earnings are taxable in the year distributed. Miss April 15 and the excess stays in the plan, is taxed in the contribution year, and is taxed again when it eventually comes out. Late distributions can also trigger a 10 percent early withdrawal penalty and mandatory 20 percent withholding.
One Change Coming After 2026
For tax years beginning after December 31, 2026, employees whose wages from the plan-sponsoring employer exceed a designated threshold will be required to make all catch-up contributions as Roth rather than pre-tax.9Internal Revenue Service. Treasury, IRS Issue Final Regulations on New Roth Catch-Up Rule It doesn’t affect 2026 contributions, but if you’re age 50 or older and earn above the threshold, your 2027 catch-up strategy will need to account for it. The final regulations are out, so the timeline is firm.