What Is a Roth Deferral in a 401(k)? Limits and Withdrawals

A Roth deferral in a 401(k) is an after-tax contribution you direct from your paycheck into a designated Roth account inside your employer’s plan. You pay income tax on the money in the year you earn it, and in exchange, qualified withdrawals in retirement come out completely tax-free, including every dollar of investment growth. For 2026, you can defer up to $24,500 this way, with additional catch-up room if you’re 50 or older. The trade is simple: no tax break today, no tax bill later.

How the Money Moves

When you elect Roth deferrals, your employer withholds the contribution from your gross pay just like a traditional 401(k) deferral. The difference is that the amount stays in your taxable income for the year, so federal and state income tax hit your current paycheck instead of getting deferred to retirement. Once those after-tax dollars land in your designated Roth account, the plan tracks them separately from any pre-tax balances you also hold.¹

That separate accounting matters. Contributions and their earnings need distinct tracking so the plan knows which dollars already had tax paid and which didn’t. You can split your deferrals between Roth and traditional in any proportion you want, as long as the combined total stays within the annual limit. You don’t have to pick one lane.

2026 Contribution Limits

The annual deferral cap under Section 402(g) for 2026 is $24,500. That ceiling applies to the combined total of your traditional pre-tax and Roth after-tax deferrals across every 401(k) plan you participate in during the calendar year.²

If you’re 50 or older by the end of 2026, you can add $8,000 in catch-up contributions, bringing your personal ceiling to $32,500. A SECURE 2.0 provision creates a higher catch-up tier for participants who turn 60, 61, 62, or 63 during the year: those workers can contribute up to $11,250 in catch-up contributions for 2026, for a combined total of $35,750.²

If you accidentally exceed the $24,500 base limit (easy to do if you switch employers mid-year and contribute to two plans), you need to pull the excess out by April 15 of the following year. Miss that deadline and you get taxed twice on the overage: once in the year you contributed it, and again when it’s eventually distributed.³

Getting the Money Out Tax-Free

The whole point of paying tax upfront is what happens at the end. To pull everything, contributions and years of growth, out with zero federal income tax, your distribution has to qualify under 26 U.S.C. Section 402A. Two conditions have to be satisfied at the same time.

First, you need to clear a five-taxable-year waiting period. The clock starts on January 1 of the first year you made any designated Roth contribution to the plan. If your first Roth deferral hit in March 2024, the five-year period began January 1, 2024, and ends December 31, 2028.⁴

Second, the distribution has to be triggered by one of three events: reaching age 59½, becoming disabled, or death. When both conditions are met, the entire withdrawal comes out federal-income-tax-free.⁴

Taking Money Out Early

Pull money before you meet both requirements and the IRS treats the distribution as non-qualified. Your original contributions come back tax-free because you already paid tax on them, but the earnings portion is taxable income. The split isn’t your call. Each non-qualified withdrawal is divided proportionally based on the ratio of your total Roth contributions to your total Roth account balance. If contributions make up 90% of the account, then 90% of the withdrawal is tax-free and 10% is taxable earnings.¹

The taxable earnings piece may also get hit with a 10% early withdrawal penalty if you’re under 59½ and don’t qualify for an exception. Typical exceptions include disability and certain separations from service after age 55. One boundary worth knowing: 401(k) plans do not offer a first-time homebuyer exception. That penalty exemption exists only for IRAs.⁵

Hardship withdrawals aren’t a shortcut either. If your plan allows them, you’ll owe income tax on any previously untaxed earnings included in the withdrawal, and the 10% early withdrawal penalty may apply on top of that if you’re under 59½.⁶

Employer Match on a Roth Basis

Traditionally, employer matching contributions always went into your pre-tax account regardless of whether your own deferrals were Roth. SECURE 2.0 changed that by letting plans offer the option to receive employer matching and nonelective contributions as Roth contributions.⁷

The tax mechanics work a little differently than your own Roth deferrals. When your employer puts matching dollars into your Roth account, the amount counts as gross income for the year, but payroll taxes (Social Security and Medicare) are not withheld. The plan reports the contribution on Form 1099-R for the year it’s allocated.⁸

There’s a catch: only participants fully vested in their employer contributions can elect Roth treatment for those contributions. If you’re still on a vesting schedule, the Roth match option isn’t available, even for the portion you’ve already vested in. Many employers are still updating their plan documents and payroll systems to offer the feature, so check with your plan administrator before assuming it’s on the table.

No Income Limit on Roth Deferrals

Unlike a Roth IRA, which phases out your ability to contribute once your modified adjusted gross income crosses certain thresholds, Roth 401(k) deferrals have no income limit at all.⁹ Someone earning $500,000 a year can contribute the full $24,500 in Roth deferrals, assuming their plan offers the feature. For high earners, this is one of the few ways to build a substantial tax-free retirement balance.

There’s still an indirect constraint that can bite highly compensated employees. Every 401(k) plan must pass annual nondiscrimination tests that compare contribution rates of higher-paid workers to everyone else. For 2026, the IRS defines a highly compensated employee as someone who earned more than $160,000 from the employer in the prior year, or owns more than 5% of the business.¹⁰ Roth deferrals count in the Actual Deferral Percentage test alongside pre-tax deferrals. If rank-and-file employees aren’t contributing enough, highly compensated employees may see their own deferrals refunded or capped so the plan clears the test.¹¹ Plans that use a safe harbor design automatically satisfy these tests, so the issue mainly surfaces in plans without safe harbor provisions.

No Lifetime Required Minimum Distributions

Designated Roth accounts are now exempt from required minimum distributions during the account holder’s lifetime. The statute explicitly states that the mandatory distribution rules under Section 401(a)(9)(A) do not apply to designated Roth accounts before the participant’s death.⁴

This is a recent change. Before SECURE 2.0, Roth 401(k) accounts were subject to RMDs starting at age 73, forcing participants to take withdrawals even if they didn’t need the money. The old workaround, rolling the Roth 401(k) into a Roth IRA, is no longer required to escape lifetime RMDs. Your Roth 401(k) balance can sit and grow tax-free for as long as you live.

Mandatory Roth Catch-Up for Higher Earners

SECURE 2.0 also added a provision that forces certain higher-income participants to make their catch-up contributions on a Roth basis. Under IRS final regulations, the requirement applies to contributions in taxable years beginning after December 31, 2026. If your wages from the sponsoring employer exceeded $145,000 (indexed annually) in the prior calendar year, any catch-up contributions you make must go into your designated Roth account rather than the pre-tax side of the plan.¹²

Participants below that wage threshold can still choose traditional or Roth catch-up contributions however they prefer. The rule only strips the choice from workers who earned above the cutoff in the previous year. If you’re in the affected group and your plan doesn’t offer a Roth option, the plan may need to add one or restrict your ability to make catch-up contributions.

Rolling the Money to a New Plan or IRA

When you leave an employer, your Roth 401(k) balance can go with you. The IRS permits direct rollovers from one designated Roth account to another, so you can transfer Roth 401(k) funds into a new employer’s Roth 401(k) or 403(b) through a trustee-to-trustee transfer.¹³

Rolling into a Roth IRA is often the more popular route, but the five-year clock works differently than most people expect. When Roth 401(k) money moves into a Roth IRA, the Roth IRA’s own five-year holding period governs, not the 401(k)’s. If you’d held a Roth 401(k) for seven years but only opened a Roth IRA last year to receive the rollover, the IRA’s clock started last year. You’d need to wait out the remaining time on the Roth IRA’s five-year period before earnings qualify for tax-free treatment.⁴

Practical move: if you think you’ll eventually roll Roth 401(k) money into a Roth IRA, open and fund a Roth IRA well in advance, even with a small contribution, to start its five-year clock. That way the clock is already satisfied when the rollover arrives.

Roth or Traditional: How to Think About It

The core question is whether you’ll be in a higher or lower tax bracket when you withdraw the money. If you expect retirement income to put you in a higher bracket than you’re in today, Roth deferrals let you lock in today’s lower rate. If you’re currently in your peak earning years and expect to drop into a lower bracket after you stop working, traditional pre-tax deferrals give you the bigger tax break now, when it’s worth the most.¹⁴

Most people can’t predict their future tax bracket with much confidence, and tax rates themselves change over time. That uncertainty is a decent argument for splitting your deferrals between both types. Holding both pre-tax and Roth balances gives you flexibility in retirement to draw from whichever bucket minimizes your tax bill in any given year. Early-career workers tend to benefit more from Roth deferrals because they’re likely in a lower bracket now and have decades for tax-free growth to compound. Workers closer to retirement with high current income often get more value from the immediate deduction of traditional deferrals.

One factor people overlook: a Roth deferral effectively shelters more money. A $24,500 Roth contribution and a $24,500 pre-tax contribution look the same on paper, but the Roth contribution is worth more in after-tax purchasing power because no taxes are owed on withdrawal. If you can afford to max out either way, the Roth side leaves you with a larger real retirement balance.

1
Internal Revenue Service. Retirement Plans FAQs on Designated Roth Accounts
2
Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500
3
Internal Revenue Service. Consequences to a Participant Who Makes Excess Deferrals to a 401(k) Plan
4
Office of the Law Revision Counsel. 26 USC 402A – Optional Treatment of Elective Deferrals as Roth Contributions
5
Internal Revenue Service. Retirement Topics – Exceptions to Tax on Early Distributions
6
Internal Revenue Service. 401(k) Plan Hardship Distributions – Consider the Consequences
7
Internal Revenue Service. SECURE 2.0 Act Changes Affect How Businesses Complete Forms W-2
8
Internal Revenue Service. Instructions for Forms 1099-R and 5498 (2025)
9
Office of the Law Revision Counsel. 26 USC 408A – Roth IRAs
10
Internal Revenue Service. 2026 Amounts Relating to Retirement Plans and IRAs
11
Internal Revenue Service. 401(k) Plan Fix-It Guide – The Plan Failed the 401(k) ADP and ACP Nondiscrimination Tests
12
Internal Revenue Service. Treasury, IRS Issue Final Regulations on New Roth Catch-Up Rule, Other SECURE 2.0 Act Provisions
13
Internal Revenue Service. Rollover Chart
14
Internal Revenue Service. Roth Comparison Chart