Yes, you can contribute to both a 401(k) and a Roth 401(k) in the same year, provided your employer’s plan offers both account types. Federal law lets employers pair a designated Roth contribution program with the standard pre-tax 401(k), and any employee who meets the plan’s normal eligibility rules can fund either bucket, or both, in whatever ratio they choose.1Office of the Law Revision Counsel. 26 USC 402A – Optional Treatment of Elective Deferrals as Roth Contributions Your combined deferrals across both accounts have to stay under one shared IRS cap, which is $24,500 for 2026.2Internal Revenue Service. Retirement Topics – 401(k) and Profit-Sharing Plan Contribution Limits
How the Split Works
Whether you have this choice at all depends on your employer’s plan documents. The company has to affirmatively add a Roth option. When it does, you don’t need a separate enrollment or a different provider. You simply tell payroll how much of each paycheck goes to the traditional side and how much to the Roth side. Check your Summary Plan Description or benefits portal to confirm both options are live.
One detail worth knowing up front: unlike a Roth IRA, a Roth 401(k) has no income ceiling. High earners who are phased out of direct Roth IRA contributions can still fund a Roth 401(k) without restriction.3Internal Revenue Service. Roth Comparison Chart That makes the workplace Roth especially useful if your salary shuts you out of the IRA version.
The Shared 2026 Contribution Limit
The IRS sets a single cap on all elective deferrals you make across traditional and Roth 401(k) accounts in a calendar year. For 2026, that cap is $24,500.4Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500 Put $16,000 into the traditional side and you have $8,500 left for the Roth side. Any ratio is fine, as long as the total lands at or below the cap. 50/50, 80/20, or all of one and none of the other all work.
If you hold 401(k) accounts at more than one employer during the year, which happens after a job change or when you work two jobs, the $24,500 limit applies across all of them combined. Each employer’s payroll system tracks only its own plan, so nobody catches the overlap except you. Going over creates an excess deferral, and fixing it means the money can end up taxed twice.
Catch-Up Contributions After 50
If you turn 50 or older during 2026, you can defer beyond the standard cap. The catch-up allowance for 2026 is $8,000, so your total employee deferral can reach $32,500.4Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500 Catch-up dollars can be split between traditional and Roth the same way regular deferrals can.
SECURE 2.0 added a higher catch-up tier for employees aged 60 through 63. If you fall in that age band during 2026, your catch-up limit rises to $11,250, pushing your maximum to $35,750.2Internal Revenue Service. Retirement Topics – 401(k) and Profit-Sharing Plan Contribution Limits The bump ends once you hit 64.
Mandatory Roth Catch-Up for Higher Earners
Starting in 2026, a new rule changes how catch-up contributions work for employees who earned more than $145,000 in FICA wages (adjusted for inflation) from their plan’s sponsoring employer in the prior calendar year.5Federal Register. Catch-Up Contributions If you clear that threshold, every catch-up dollar must go into the Roth 401(k). Pre-tax catch-ups are off the table.
The practical consequence catches people off guard: if you’re over 50, over the wage threshold, and your employer’s plan has no Roth option, you can’t make catch-up contributions at all. Employees under the threshold still get the free choice between account types.
Why People Split Their Contributions
The point of funding both is tax diversification. Traditional 401(k) contributions come out of pre-tax pay, cutting your taxable income now, and you pay tax later when you withdraw. Roth 401(k) contributions come out of after-tax pay, with no break today, but qualified withdrawals in retirement come out tax-free, including all the growth.3Internal Revenue Service. Roth Comparison Chart
Nobody knows their future tax bracket with certainty. If your rate ends up higher in retirement, the Roth money wins. If it ends up lower, the traditional money wins. Splitting the difference hedges the bet. Peak-earning years often push people toward traditional contributions for the immediate deduction; lower-income years often push them toward Roth. Having balances in both gives you flexibility when it’s time to draw down.
Where the Employer Match Lands
Employer matching has traditionally gone into a pre-tax bucket no matter where you direct your own contributions. Even if you route 100% of your money to the Roth side, the match lands on the traditional side and gets taxed as ordinary income when you withdraw it.
SECURE 2.0 lets employers offer Roth matching contributions if they choose. When the plan allows it, you can elect to take the match as a designated Roth contribution.6Internal Revenue Service. SECURE 2.0 Act Impacts How Businesses Complete Forms W-2 A Roth match counts as taxable income in the year it’s contributed, and the plan will issue a Form 1099-R so you can report it. Most plans still default to the traditional pre-tax model for matches, so ask your plan administrator if you want to change that treatment.
Withdrawal Rules and the Five-Year Clock
The tax-free treatment of Roth 401(k) withdrawals is conditional. A qualified distribution requires two things: the account has been open for at least five consecutive tax years since your first Roth 401(k) contribution, and you’re at least 59½ (or the withdrawal is due to disability or death).7Internal Revenue Service. Retirement Plans FAQs on Designated Roth Accounts Miss either condition and the earnings portion of your withdrawal becomes taxable.
The five-year clock starts on January 1 of the year of your first Roth 401(k) contribution to that specific plan. A first contribution in March 2024 means the clock started January 1, 2024, and the requirement is satisfied on January 1, 2029. Rolling a Roth 401(k) from a previous employer into your new employer’s Roth account can carry the earlier start date forward, so confirm that during any job change.
Withdrawals before 59½ from either side generally trigger a 10% early distribution penalty on top of income tax. Exceptions exist for separation from service at 55 or older, disability, certain medical expenses, qualified domestic relations orders, and others.8Internal Revenue Service. Retirement Topics – Exceptions to Tax on Early Distributions
If You Go Over the Limit
Contributing more than the annual cap creates an excess deferral, and the IRS wants it corrected by April 15 of the following year. If your plan distributes the excess plus any earnings on it by that date, you report the excess as income in the year it was contributed and you’re done.9Internal Revenue Service. Retirement Topics – What Happens When an Employee Has Elective Deferrals in Excess of the Limits
Miss the April 15 deadline and the money is taxed twice: once in the year of contribution, and again when you eventually withdraw it.10Internal Revenue Service. Consequences to a Participant Who Makes Excess Deferrals to a 401(k) Plan The scenario most likely to produce an excess is working for two employers in the same year. Neither payroll system sees the other, so tracking the combined total is on you. If you go over, call your plan administrator right away.
Setting or Changing Your Split
Adjusting the allocation between traditional and Roth is usually a quick task in the plan provider’s benefits portal. Find the retirement or savings section and update the percentage or dollar amount going to each account type. Some plans accept changes every pay period; others limit changes to quarterly windows. Expect one or two pay cycles before the change shows up.
Before you submit, pull a recent pay stub so you can see what’s currently being deducted and confirm the new split keeps you under the annual cap. If your employer still uses paper, you’ll sign a salary reduction agreement with the new allocation. Either way, check the next couple of pay stubs to verify the right amounts are hitting each account.