A Roth 401(k) is an employer-sponsored retirement savings wrapper that combines the high contribution limits of a traditional 401(k) with the tax-free growth of a Roth IRA. You fund a Roth 401(k) with after-tax dollars; your contributions do not reduce your current year’s taxable income, but qualified distributions in retirement are completely tax-free.
This structure offers a massive tax-diversification tool for high earners. The Roth 401(k) shares the employee elective deferral limit with the pre-tax 401(k). In 2026, you can contribute up to $24,500 (or $32,500 if you are age 50 or older, thanks to the $8,000 catch-up provision) to either account, or split your deferrals between them in any proportion. Unlike a personal Roth IRA, which shuts the door on high earners via strict income phase-outs, the Roth 401(k) has no income limits. If you make $1M as a corporate executive, you can still defer the full $24,500 into a Roth 401(k).
Under SECURE 2.0, employers may offer employees the option to receive employer matching and non-elective contributions directly into their Roth 401(k) sub-account, rather than the traditional pre-tax sub-account. However, there is a catch: any employer match designated as a Roth contribution is treated as taxable ordinary income to you in the year it is made, though it will grow and eventually be distributed tax-free. If your employer does not yet support this or you prefer to defer the tax drag, employer matching contributions default to a traditional, tax-deferred 401(k) account.
A Roth 401(k) carries no lifetime RMD requirements. SECURE 2.0 eliminated these mandatory distributions beginning in 2024, bringing the vehicle into parity with the Roth IRA. However, if you plan to roll your Roth 401(k) into a personal Roth IRA upon separation from service, you must pay attention to the five-year rule. To withdraw Roth IRA earnings tax-free, the Roth IRA must have been open for at least five tax years. The five-year clock on your Roth 401(k) does not transfer to the Roth IRA. Instead, the rolled-over assets adopt the timeline of the receiving Roth IRA. If you already have a personal Roth IRA that has been open for at least five years, the rolled-over Roth 401(k) earnings are immediately qualified for tax-free withdrawal. If you do not own an existing Roth IRA, the clock starts from the year you establish the account, creating a needless tax trap. The strategic takeaway is clear: open a personal Roth IRA today and seed it with a nominal contribution to start the five-year clock, even if your income prevents direct annual contributions.