Retirement planning
Traditional vs. Roth 401(k)
Reviewed by the Smart Finance Calculators Editorial TeamLast reviewed:
Many employer 401(k) plans let you choose between traditional (pre-tax) and Roth (after-tax) contributions. The accounts hold the same investments; the only difference is when you pay income tax — now or in retirement. That single choice can meaningfully change your after-tax retirement income.
This guide explains how each is taxed, the factors that tip the decision, how the employer match is handled, and the 2025 and 2026 contribution limits to keep in mind. The employee elective-deferral limit is $23,500 for 2025 and rises to $24,500 for 2026, and that limit applies to your traditional and Roth contributions combined.
Key takeaways
- Traditional 401(k) contributions are pre-tax now and taxed as income when withdrawn.
- Roth 401(k) contributions are after-tax now, and qualified withdrawals are tax-free.
- Traditional and Roth employee contributions share one combined annual limit: $23,500 in 2025 and $24,500 in 2026 — you cannot contribute the full limit to each.
- Roth tends to win if you expect a higher tax rate in retirement than today.
- Employer matching contributions do not reduce your employee elective-deferral limit.
How each is taxed
Traditional (pre-tax)
Traditional contributions are generally made before federal income tax, reducing your taxable income in the year you make them and lowering your current tax bill, subject to applicable rules. The money grows tax-deferred, and both contributions and growth are taxed as ordinary income when you withdraw in retirement.
Roth (after-tax)
Roth contributions are generally made after tax — with money you have already paid tax on — so there is no upfront deduction. In exchange, qualified withdrawals in retirement, including all the growth, are completely tax-free. Neither option guarantees investment growth or tax savings.
One combined limit for traditional and Roth
Traditional and Roth 401(k) employee contributions share one combined annual employee-deferral limit. You cannot contribute the full annual limit separately to both account types — the limit applies to the combined total of your traditional and Roth employee deferrals.
In 2026, an employee younger than age 50 could contribute a combined total of up to $24,500 across traditional and Roth 401(k) contributions. For example, the employee could contribute $14,500 to a traditional 401(k) and $10,000 to a Roth 401(k), but not $24,500 to each.
Employer matching contributions do not reduce this employee elective-deferral limit. However, employer contributions may count toward a separate overall plan contribution limit that combines employee and employer money.
Contribution and catch-up limits for 2025 and 2026
The employee elective-deferral limit is $23,500 for 2025 and $24,500 for 2026. Participants who reach age 50 or older by the end of the year may make an additional regular catch-up contribution: $7,500 in 2025 and $8,000 in 2026.
Eligible participants ages 60 to 63 may instead make an enhanced catch-up of $11,250 in both 2025 and 2026. The enhanced catch-up replaces the regular age-50 catch-up amount for those participants; it is not added on top of it. Age eligibility is generally based on the participant’s age by the end of the calendar year, and the employer’s plan must allow catch-up contributions.
Worked example: $10,000 contributed, 22% tax rate
Say you contribute $10,000 and are in the 22% bracket. With a traditional 401(k), the full $10,000 goes in and you save $2,200 in tax today; if it grows to $40,000 and you withdraw at a 22% rate, you keep about $31,200.
With a Roth, contributing the same $10,000 costs you $10,000 of take-home pay (no deduction). It grows to $40,000, and you withdraw the entire $40,000 tax-free.
If your retirement tax rate is higher than 22%, the Roth wins clearly. If it is lower, the traditional can come out ahead. When rates are identical, the two are mathematically equivalent for the same contribution.
Traditional vs. Roth 401(k)
| Feature | Traditional 401(k) | Roth 401(k) |
|---|---|---|
| Tax on contributions | Before federal income tax | After tax |
| Tax on qualified withdrawals | Taxed as income | Tax-free |
| Best when | Lower tax rate in retirement | Higher tax rate in retirement |
| Employee deferral limit | Shared: $23,500 (2025) / $24,500 (2026) | Shared: $23,500 (2025) / $24,500 (2026) |
| Employer match | Does not reduce employee limit | Does not reduce employee limit |
The employee limit is shared across both account types. Figures reflect 2025 and 2026 IRS guidance ($23,500 in 2025, $24,500 in 2026); verify current figures before relying on them.
2025 vs. 2026 401(k) contribution limits
| Contribution rule | 2025 | 2026 |
|---|---|---|
| Employee elective-deferral limit | $23,500 | $24,500 |
| Regular catch-up, age 50+ | $7,500 | $8,000 |
| Enhanced catch-up, ages 60–63 | $11,250 | $11,250 |
| Maximum for most participants age 50+ | $31,000 | $32,500 |
| Maximum for eligible participants ages 60–63 | $34,750 | $35,750 |
Age eligibility is generally based on the participant’s age by the end of the calendar year, and the employer’s plan must allow catch-up contributions. The enhanced catch-up for ages 60–63 replaces the regular age-50 catch-up; it is not added on top of it. Last reviewed and verified: July 21, 2026. Primary source: Internal Revenue Service.
2026 Roth catch-up notice
Beginning in 2026, some higher-paid participants may be required to make catch-up contributions on a Roth (after-tax) basis, depending on their prior-year wages and the terms of the employer plan. Whether this applies to you depends on IRS rules and your specific plan.
This guide does not make a personalized determination of whether your catch-up contributions must be Roth. Confirm how the rule applies with your plan administrator or a qualified tax professional and the current IRS guidance linked below.
Which one wins for you?
The core question is whether your tax rate will be higher now or in retirement. If you expect to be in a higher bracket later — common for younger workers early in their careers — the Roth’s tax-free withdrawals are usually more valuable.
If you are in your peak earning years and expect a lower bracket in retirement, the traditional deduction now may be worth more. Because the future is uncertain, some savers split contributions between both to diversify their tax exposure. Neither option guarantees investment growth or tax savings.
How to use the 401(k) Growth Calculator
Project your 401(k) balance with employee and employer contributions, applying the current year’s contribution and catch-up limits.
Open the 401(k) Growth CalculatorCommon mistakes to avoid
- Contributing too little to earn the full employer match.
- Assuming your tax rate in retirement without estimating it.
- Forgetting that the employer match is pre-tax and taxable when withdrawn, even in a Roth.
- Overlooking catch-up contributions available at age 50 and older.
Practical takeaways
- Capture the full employer match before optimizing the tax choice.
- Choose Roth if you expect higher future taxes; traditional if lower.
- Splitting contributions can hedge against uncertain future tax rates.
- Revisit the choice when your income or tax law changes.
Frequently asked questions
For 2026, the employee elective-deferral limit is $24,500, up from $23,500 in 2025. This limit applies to the combined total of your traditional and Roth 401(k) employee contributions, and it does not include employer matching contributions. Verify the current figure with the IRS, as limits are adjusted periodically for inflation.
No. Traditional and Roth 401(k) employee contributions share one combined annual employee-deferral limit — $23,500 in 2025 and $24,500 in 2026. You cannot contribute the full annual limit separately to each account type; the limit applies to the combined total of your traditional and Roth deferrals.
For 2026, participants who reach age 50 or older by the end of the year may make an additional regular catch-up contribution of $8,000, up from $7,500 in 2025. That raises the maximum employee contribution to $32,500 for 2026. The employer plan must allow catch-up contributions.
Eligible participants who are ages 60 to 63 by the end of the calendar year may make an enhanced catch-up of $11,250 in both 2025 and 2026, if the employer plan allows it. This enhanced amount replaces the regular age-50 catch-up for those participants; it is not added on top of it. It brings the maximum employee contribution to $35,750 for 2026.
No. Employer matching contributions do not reduce or count against your employee elective-deferral limit. However, employer contributions may count toward a separate overall plan contribution limit that combines employee and employer money. Check your plan documents for how your match is structured.
Yes, if your plan offers both, you can split your contributions between them in any proportion, as long as your combined total stays within the annual employee elective-deferral limit. Splitting is a common way to diversify your future tax exposure, since Roth contributions are made after tax and traditional contributions are generally made before federal income tax.
Generally, yes. The IRS reviews retirement-plan contribution limits annually and adjusts them for inflation, so they often change from year to year — for example, the employee limit rose from $23,500 in 2025 to $24,500 in 2026. Always confirm the current-year figures with the IRS before relying on them.
Beginning in 2026, some higher-paid participants may be required to make their catch-up contributions on a Roth (after-tax) basis, depending on prior-year wages and the terms of the employer plan. Whether this applies to you depends on IRS rules and your specific plan, so confirm with your plan administrator or a qualified tax professional. This guide does not make a personalized determination.
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Related guides
- How Much to Save for RetirementFrom the 15% savings rate to the 25x rule — practical ways to set a retirement target you can act on.
- How Federal Income Tax Brackets WorkBeing "in the 22% bracket" does not mean you pay 22% on everything — here is how progressive tax really works.
- How Inflation Affects RetirementA comfortable income today may not stretch as far in 20 years — here is how to plan for that.
Sources and methodology
This article is based on general financial principles and information published by the authoritative primary sources below. Figures are illustrative and rounded to explain the concepts.
- Internal Revenue Service — 401(k) limit increases to $24,500 for 2026 (Notice 2025-67)
- Internal Revenue Service — 401(k) limit increases to $23,500 for 2025
- Internal Revenue Service — Retirement topics: 401(k) and profit-sharing plan contribution limits (catch-up rules)
- Internal Revenue Service — SECURE 2.0 Act: higher catch-up limit for ages 60 to 63
- Internal Revenue Service — Roth catch-up contribution requirement guidance
- Internal Revenue Service — Roth account in your retirement plan
Last reviewed and verified: July 21, 2026. Primary source: Internal Revenue Service.
About this article
Written and reviewed by the Smart Finance Calculators Editorial Team.
Published · Last reviewed
Financial disclaimer: Results are estimates for educational purposes only and are not professional financial, tax, legal or investment advice. Figures may not reflect your exact situation. Consult a qualified professional before making financial decisions.