401k Calculator & Guide
A Roth 401(k) lets you make retirement contributions with after-tax dollars. Learn how Roth contributions work, how taxes are handled, contribution limits, employer matching, withdrawals and how Roth compares with a traditional 401(k).
A Roth 401(k) is a designated Roth account offered within an eligible employer retirement plan. Contributions are made with after-tax income rather than reducing your current taxable income.
Roth 401(k) contributions are included in your gross income for the year in which you make them.
Your contributions are invested through the options offered by your employer's 401(k) plan.
Qualified Roth distributions, including qualifying earnings, are generally excluded from gross income.
The main difference from a traditional pre-tax 401(k) is when the contribution is taxed.
Your plan must offer a designated Roth contribution feature.
A percentage or dollar amount is deferred from your paycheck as a Roth contribution.
Roth contributions are included in taxable income when made.
If distribution requirements are satisfied, the Roth distribution is generally tax-free.
Roth does not mean “no taxes.” The key distinction is that Roth contributions are generally taxed before they enter the account, while qualified withdrawals can generally come out without federal income tax.
Designated Roth contributions are included in your gross income. They do not receive the same current-year pre-tax treatment as traditional elective deferrals.
A qualified distribution from a designated Roth account is generally excluded from gross income, including qualifying earnings.
Both can be part of the same employer retirement plan. Their major difference is the tax treatment of contributions and qualified withdrawals.
Contributions are made after tax. Qualified distributions are generally excluded from gross income.
Traditional pre-tax elective deferrals generally aren't included in current taxable income, with taxes generally applying when amounts are distributed.
Roth 401(k) contributions share the applicable 401(k) elective-deferral limit with traditional pre-tax elective deferrals.
This limit applies to your combined traditional pre-tax and designated Roth elective deferrals across applicable plans.
Yes. If your employer plan permits both types, you can split your elective deferrals between traditional pre-tax and designated Roth contributions.
| Example | Traditional | Roth | Combined |
|---|---|---|---|
| Example A | $24,500 | $0 | $24,500 |
| Example B | $12,250 | $12,250 | $24,500 |
| Example C | $6,000 | $18,500 | $24,500 |
| Example D | $0 | $24,500 | $24,500 |
Examples illustrate the 2026 basic elective-deferral limit and do not account for catch-up contributions or individual plan rules.
An employer can use designated Roth contributions when calculating a matching contribution if the plan provides matching contributions.
Your designated Roth contribution goes into your designated Roth account and is treated as an employee elective deferral.
The employer match cannot be deposited directly into your designated Roth account under the IRS designated Roth rules. It is allocated to another account within the plan.
Roth 401(k) withdrawals have specific rules. A qualified distribution generally requires the applicable five-taxable-year period and a qualifying event.
The qualified-distribution period generally begins with the first taxable year for which you make a designated Roth contribution to the plan.
Reaching age 59½ is one of the events that can satisfy the qualifying-distribution requirement.
Disability or death can also satisfy the qualifying event requirement under the applicable rules.
Both use Roth tax treatment, but they are different retirement accounts with different contribution and plan rules.
Employer-sponsored retirement plan feature. The plan determines the available investment menu and other plan provisions.
Individual retirement account with its own contribution, income eligibility and tax rules.
Roth 401(k) and Roth IRA contributions are governed by different annual limits and eligibility rules.
Your employer's plan document and Summary Plan Description determine the specific features available to you.
Use the Roth 401(k) calculator to explore an illustrative projection and compare Roth and traditional contribution scenarios.
Clear guides, useful calculators and practical retirement resources to help you understand your 401(k), contributions, employer matching, Roth options, rollovers and long-term savings.
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