Traditional 401(k) and Roth 401(k) contributions are combined under a single IRS limit, not tracked separately. For 2026, that shared cap is $24,500, and it applies to the total you defer across both account types in the same year.1Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500 Put $10,000 into your traditional 401(k), and you have $14,500 of room left for the Roth side. Any split works, as long as the two together stay at or under the cap.
Why One Limit Covers Both Accounts
The rule comes from 26 U.S.C. § 402(g), which treats all elective deferrals as a single pool regardless of the tax treatment you choose.2Office of the Law Revision Counsel. 26 USC 402 – Taxability of Beneficiary of Employees Trust The same statute covers 403(b) plans, the federal Thrift Savings Plan, and SIMPLE plans, and the base dollar amount is adjusted each year for inflation. So the choice between traditional and Roth is a choice about when you pay tax on the money, not about how much you can set aside.
Catch-Up Contributions Share the Cap Too
If you turn 50 or older at any point in the calendar year, you can contribute above the standard $24,500. The 2026 catch-up allowance is $8,000, which brings the combined maximum to $32,500 for most eligible participants.1Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500 Those catch-up dollars follow the same combined rule: you can put them in the traditional account, the Roth account, or split them between the two, but the $8,000 is one budget, not two.
A higher catch-up applies if you are 60, 61, 62, or 63 during the year. Under a SECURE 2.0 Act change, participants in that age band can contribute up to $11,250 in catch-up dollars for 2026.1Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500 A 62-year-old could therefore defer as much as $35,750 across their traditional and Roth accounts combined. At 64, the catch-up drops back to $8,000.
Employer Contributions Are Tracked Separately
The $24,500 cap covers only your own elective deferrals. Employer matching and non-elective employer contributions live under a different, higher ceiling in 26 U.S.C. § 415(c): the lesser of 100% of your compensation or $72,000 for 2026, counting everything flowing into the plan from all sources.3Office of the Law Revision Counsel. 26 USC 415 – Limitations on Benefits and Contribution Under Qualified Plans Catch-up contributions sit on top, so the effective total addition ceiling reaches $80,000 for those 50 and older, and $83,250 for the 60-through-63 group.4Internal Revenue Service. Retirement Topics – 401(k) and Profit-Sharing Plan Contribution Limits An employer match does not eat into your $24,500 of personal room.
Multiple Employers Don’t Reset the Limit
The $24,500 cap follows you, not the job. If you work for more than one employer during the year, you have to add together every elective deferral across every 401(k), 403(b), or similar plan you participate in.4Internal Revenue Service. Retirement Topics – 401(k) and Profit-Sharing Plan Contribution Limits Maxing out at your first job means no further elective deferrals at a second, unrelated employer, even though each plan has its own separate § 415(c) tracking. Unrelated employers cannot coordinate for you, so the responsibility to stay under the combined cap sits with you.
When You Lose the Choice Between Traditional and Roth
Higher earners will soon lose flexibility over one slice of their contributions. Under a SECURE 2.0 Act rule, if your FICA wages from the prior year exceeded $150,000 (the 2026 threshold, based on 2025 wages), your catch-up contributions must be designated as Roth rather than traditional pre-tax.5Internal Revenue Service. 2026 Amounts Relating to Retirement Plans and IRAs, as Adjusted for Changes in Cost-of-Living – Notice 2025-67 The IRS issued final regulations in 2025, with the requirement generally taking effect for contributions in taxable years beginning after December 31, 2026.6Internal Revenue Service. Treasury, IRS Issue Final Regulations on New Roth Catch-Up Rule, Other SECURE 2.0 Act Provisions
This affects only the catch-up portion. Your regular deferrals up to $24,500 can still go to either account type at any income level. Below the $150,000 wage threshold, you keep full flexibility on catch-up dollars as well. Plan administrators are rolling out the change on their own timelines, so ask yours how it will apply to your account.
What Happens If You Go Over the Combined Cap
Exceeding $24,500 across your traditional and Roth accounts triggers a corrective distribution. You need to notify the plan and have the excess amount, plus any earnings on it, paid back to you no later than April 15 of the following year.7Internal Revenue Service. Consequences to a Participant Who Makes Excess Deferrals to a 401(k) Plan That deadline is firm and does not move if you file a tax extension.
Corrected on time, the excess is taxable in the year you contributed it, and nothing more happens. Miss the April 15 window and the IRS taxes the excess in the contribution year and again when the money is eventually distributed from the plan.7Internal Revenue Service. Consequences to a Participant Who Makes Excess Deferrals to a 401(k) Plan That double-taxation risk is the main reason to reconcile deferrals early, especially if you switched jobs mid-year or contributed to plans at two different employers.