Roth vs Traditional 401(k) on $300k income? (single)
At $300k, most people assume Roth is the smart move because 'taxes are going up.' But your specific numbers tell a different story.
The setup
Age
35
Household income
$300,000/yr
Household
Single earner
Liquid savings
$132,000
Retirement savings
$396,000
Investing return
7%/yr
Lean Traditional — your 30% rate drops to ~20% in retirement
30% → 20%
Rate drops 10% in retirement
Rate Now
30%
Rate Retired
20%
Best Strategy
All Trad
NW Diff
+$381k
Your marginal rate right now is 30%, and the engine projects it dropping to roughly 20% in retirement. That 10-point spread is the whole game: every dollar you shelter in a Traditional 401(k) today gets taxed at 20% on the way out instead of 30% on the way in, and across a career that arithmetic compounds into a projected $381k net worth difference in Traditional's favor.
Your current effective rate of ~30% (engine-computed) drops to ~20% in retirement. Traditional saves taxes now when your rate is highest. The All Trad strategy produces +$381k more at retirement.
| Scenario | Strategy | Retire NW | Lifetime Taxes | Retire SWR/mo | Coverage |
|---|---|---|---|---|---|
| All Trad | 100% Traditional | $23,390,289 ($9.6M in today's dollars) | $12M | $77,968 | 25 yrs |
| Current | Current mix | $23,009,382 ($9.5M in today's dollars) | $11M | $76,698 | 25 yrs |
| 50/50 | 50/50 Split | $22,733,322 ($9.4M in today's dollars) | $11M | $75,778 | 25 yrs |
| Roth 70% | Tilt Roth (70%) | $22,384,048 ($9.2M in today's dollars) | $9.9M | $74,613 | 25 yrs |
| All Roth | 100% Roth | $22,074,869 ($9.1M in today's dollars) | $9.3M | $73,583 | 25 yrs |
Tax laws change. Roth conversions, RMDs, and state tax changes can shift the calculus. This analysis uses current rates as a starting point.
Run your own income and savings mix through the model, because a 10-point rate gap is the kind of thing that's easy to miss and expensive to ignore.
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Get my verdict →Frequently asked
Roth or traditional 401(k) for a single household earning $300k?
Lean Traditional — your 30% rate drops to ~20% in retirement
Rate drops 10% in retirement
30% → 20%, modeled with Rightmont's projection engine for this exact scenario.
How was this calculated?
Rightmont runs your numbers through a year-by-year projection engine (taxes, compounding, Social Security, and your real cashflow) to model the outcome. Model your own version free in under a minute.
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For educational purposes only — not financial advice.