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Choose when you pay tax.

Compare the retirement value of Traditional and Roth 401(k) contributions using your marginal tax rates—not a generic rule of thumb.

Your assumptions

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Projection at age 65 · 30 years

Projection results

TRADITIONAL 401(k)
$0
spendable at retirement
ROTH 401(k)
$0
spendable at retirement
—
Traditional tax paid later$0
Roth tax paid now, over time$0
Roth tax paid later on pre-tax money$0
Annual contribution / gross income0%
0%
combined retirement tax rate

Your breakeven rate

If your retirement tax rate lands above this, Roth is favored for new employee contributions. Below it, Traditional is favored.

After-tax value by age

Projected after-tax retirement value by ageTraditional and Roth values over time.

Values apply the expected retirement tax rate to each year's projected pre-tax money.

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High income? Know the distinction.

A Roth 401(k) has no income limit for contributions, though your plan and annual IRS contribution limits still apply.

Direct Roth IRA contributions do have income phaseouts. A backdoor Roth IRA may be an option, but pre-tax IRA balances can trigger the pro-rata rule. Check the current limits and your full IRA picture before acting.

How this model works

  • Uses the same employee contribution in both accounts; Roth therefore costs more in current take-home pay.
  • Treats employer match and the current balance as pre-tax in both scenarios.
  • Contributions occur at year-end and returns are constant; fees, inflation, payroll taxes, and tax-law changes are excluded.
  • “Tax paid now” is the estimated incremental income tax on Roth contributions, summed without discounting.

Educational estimates only—not tax, legal, or financial advice. Tax treatment depends on plan rules, account history, residency, withdrawal timing, and future law. Consider a qualified tax or financial professional for decisions.