A Roth 401(k) is a workplace retirement account that combines features of a traditional 401(k) with the tax-free growth of a Roth IRA. Contributions come from after-tax dollars — you pay taxes now, but qualified withdrawals in retirement are completely tax-free.
How a Roth 401(k) Differs from a Traditional 401(k)
| Roth 401(k) | Traditional 401(k) | |
|---|---|---|
| Contributions | After-tax (no upfront deduction) | Pre-tax (reduces taxable income now) |
| Growth | Tax-free | Tax-deferred |
| Withdrawals in retirement | Tax-free (qualified) | Taxed as ordinary income |
| RMDs | Not required (SECURE 2.0, 2024) | Required starting at age 73 |
| Contribution limits (2026) | $23,500 ($31,000 if 50+) | Same |
Roth 401(k) vs. Roth IRA
- Contribution limits: Roth 401(k) limit is $23,500 in 2026. Roth IRA limit is $7,000 ($8,000 if 50+).
- Income limits: Roth 401(k) has no income limit. Roth IRA phases out for high earners.
- Employer match: Roth 401(k) can receive employer matching. Roth IRA cannot.
How Employer Matching Works
If your employer offers a match, they will match your Roth 401(k) contributions — but the match itself goes into a traditional (pre-tax) account. Only your own Roth contributions grow and withdraw tax-free.
Who Should Choose the Roth 401(k)?
Choose Roth 401(k) if:
- You are early in your career and in a low tax bracket
- You expect to be in a higher tax bracket in retirement
- You earn too much to contribute to a Roth IRA directly
- You want to avoid RMDs and preserve assets for heirs
Choose Traditional 401(k) if:
- You are in a high tax bracket now and expect lower taxes in retirement
- You need the upfront deduction to afford larger contributions
Consider splitting contributions:
Many advisors recommend contributing to both Roth and traditional 401(k) for tax diversification — giving you flexibility to manage taxable income in retirement.
Qualified Withdrawals: The Rules
For Roth 401(k) withdrawals to be tax-free and penalty-free:
- You must be at least 59½ years old, and
- The account must have been open for at least 5 years
In-Plan Roth Conversion
Some plans allow you to convert existing traditional 401(k) balances to Roth within the plan. You pay income tax on the converted amount in the year of conversion, but future growth and withdrawals are tax-free. Valuable during low-income years.
Bottom Line
The Roth 401(k) is increasingly powerful after the SECURE 2.0 changes. If your employer offers it, it is worth serious consideration — particularly for younger workers or anyone who values tax-free income in retirement. When in doubt, splitting contributions between Roth and traditional is a flexible strategy for most people.