Roth vs Traditional 401(k) (2026): The Deduction Now Against the Tax Later
Compare the tax a traditional deferral saves now with the tax on taking it out later. For a single filer retiring on $50,000, the two are equal up to about $60,000 of salary, and traditional pulls ahead from around $85,000. Below that, Roth costs nothing extra and buys flexibility later.
A traditional 401(k) deferral is deducted now and taxed when it comes out. A Roth deferral is taxed now and never again. With the same tax rate at both ends, they leave you with exactly the same money. Every argument for one over the other is really an argument about which rate will be lower.
The comparison, by salary
| Salary, single | Tax saved deferring $10,000 | Tax withdrawing it later | Better |
|---|---|---|---|
| $40,000 | $1,200 | $1,200 | Even |
| $60,000 | $1,200 | $1,200 | Even |
| $85,000 | $2,200 | $1,200 | Traditional |
| $120,000 | $2,200 | $1,200 | Traditional |
| $175,000 | $2,400 | $1,200 | Traditional |
| $250,000 | $3,200 | $1,200 | Traditional |
Federal income tax only, 2026 brackets and standard deduction. Withdrawal taxed on top of $50,000 of other taxable retirement income, before the extra standard deduction for those 65 and over, which would lower it.
The federal tax saved by deferring now, less the tax paid withdrawing later. Zero means the two choices leave you with the same money.
Up to $60,000 the deduction and the withdrawal tax are the same, $1,200: both are at 12%, so the choice changes nothing today. From $85,000, the deduction is at 22% or more and the withdrawal still at 12%, and traditional comes out $1,000 ahead on every $10,000.
The US result differs from what most people expect because the 12% bracket is wide. A single retiree can have about $66,500 of income, counting the standard deduction, before any of it is taxed at 22%; a married couple about twice that. A retirement income inside that range is common, which is why traditional deferrals usually win for anyone in the 22% bracket or above while working.
When an even result favors Roth
Where the table says even, Roth has the small advantages. Roth balances in a 401(k) no longer have required minimum distributions, so they can be left to grow. Roth withdrawals do not count as income, so they do not push more of your Social Security benefits into tax, which traditional withdrawals can. And a Roth dollar is worth a full dollar, which makes the $24,500 limit worth more when it is filled with Roth money: $24,500 of Roth is $24,500 you keep, while $24,500 of traditional is $24,500 less the tax still owed on it.
State tax can decide it
Traditional deferrals also cut state income tax in most states. A single Californian on $120,000 who defers $10,000 saves $930 of California tax on top of the $2,200 federal. Retire to one of the states with no income tax and that money is never taxed by any state at all. Moving the other way, from a no-tax state to one with an income tax, argues for Roth. Your state's figures are on its income tax calculator page.
The 2026 rules
| Employee deferral limit | $24,500, Roth and traditional combined |
| Catch-up, age 50 and over | $8,000 |
| Catch-up, ages 60 to 63 | $11,250 |
| Roth-only catch-up | If 2025 FICA wages from the employer exceeded $150,000 |
| Income limit for a Roth 401(k) | None |
| Required minimum distributions on Roth 401(k) | None during the owner's life, since 2024 |
The Roth catch-up rule is new for 2026, from SECURE 2.0: an employee who earned more than $150,000 in FICA wages from the employer in 2025 can still make catch-up contributions, but only as Roth. The Roth 401(k) also has no income limit, unlike the Roth IRA, so it is the simplest Roth route for a high earner. Limits in full are in 401(k) contribution limits.
Splitting, and the match
You do not have to choose one. Most plans let you split deferrals in any proportion, and splitting is a reasonable answer when you genuinely do not know your future rate: some money taxed now, some later, and a choice in retirement of which to draw from in a given year. The employer match usually goes in as traditional whatever you pick, so most people already hold some of each. Model your own rates with the Roth vs traditional calculator, and project the balance with the 401(k) calculator.
Frequently asked questions
Is a Roth or traditional 401(k) better?
Traditional if your tax rate now is higher than it will be when you withdraw; Roth if it is lower; identical if they are the same. For a single filer, deferring $10,000 saves $1,200 of federal tax at $60,000 and $2,200 at $120,000, against $1,200 of tax withdrawing it on a $50,000 retirement income.
What is the 2026 401(k) contribution limit?
$24,500 of employee deferrals, Roth and traditional combined, plus a $8,000 catch-up from age 50 and a higher $11,250 catch-up at ages 60 to 63. You can split your deferrals between the two in any proportion your plan allows.
Do high earners have to make Roth catch-up contributions?
Yes, from 2026. If your FICA wages from the employer were above $150,000 in 2025, any catch-up contributions you make in 2026 must go in as Roth. Your regular deferrals can still be traditional.
Does a traditional 401(k) reduce Social Security and Medicare tax?
No. Traditional deferrals reduce federal and most state income tax, but Social Security and Medicare are charged on wages before the deferral. Roth deferrals reduce neither, so FICA is the same either way.
Is the employer match Roth or traditional?
Traditionally the match goes in pre-tax whatever you choose for your own deferrals. Since SECURE 2.0, plans may let you take the match as Roth instead, in which case it counts as taxable income in the year it is made.
Do Roth 401(k)s have required minimum distributions?
Not any more. Since 2024, Roth balances in a 401(k) are exempt from required minimum distributions during the owner's life, as Roth IRAs always were. Traditional balances must start coming out in your 70s.
Can I contribute to a Roth 401(k) if my income is too high for a Roth IRA?
Yes. The Roth 401(k) has no income limit; the phase-out applies only to Roth IRAs. That makes the Roth 401(k) the simplest way for a high earner to save on a Roth basis.
Related guides
$7,500, or $8,600 from 50, phasing out from $153,000 single and $242,000 jointly. Two single people on $150,000 each can put in $15,000; married, nothing. A 401(k) deferral is the lever that reopens it.
No, and every page stops there. A second ceiling of $72,000 sits above the one you know about, and the $47,500 between them is the whole reason after-tax contributions exist.
Vanguard reports $167,970 average and $44,115 median, both per account at one recordkeeper. Counted per household instead, fewer than half of families under 35 hold any retirement account at all.
The 2026 deferral limit is $24,500. Catch-up rules lift it to $35,750 between 60 and 63 and then drop it back at 64, a window worth $13,000 that cannot be claimed late.
Researching and writing about Canadian personal finance since 2026.
Last reviewed October 2026 · How we research
“Roth vs Traditional 401(k) (2026): The Deduction Now Against the Tax Later.” Vault Nerd, https://www.vaultnerd.com/learn/roth-vs-traditional-401k, updated October 2026.
- IRS Revenue Procedure 2025-32: 2026 brackets and standard deduction
- IRS Notice 2025-67: 2026 deferral and catch-up limits, and the $150,000 Roth catch-up wage threshold under section 414(v)(7)
- SECURE 2.0 Act of 2022: Roth catch-up requirement, Roth employer contributions, and the end of Roth 401(k) RMDs
- Tax Foundation, 2026 State Income Tax Rates and Brackets
No product is reviewed on this page and Vault Nerd has no affiliate relationship in this category. Figures checked October 2026.