Roth vs Traditional 401(k) and IRA: Which Is Better? 2026 Limits and a Worked Comparison
Last reviewed October 8, 2026. Limits come from IRS announcements for 2026. We recalculated the example ourselves; sources are at the end.
"Should I choose Roth or traditional?" is one of the most common retirement questions, and the honest answer is that it depends on one thing you cannot know for certain: what your tax rate will be when you withdraw the money. This guide explains how the two work, gives the 2026 limits, and shows a worked comparison so you can see exactly when each one comes out ahead. You can model your own savings in the retirement and 401(k) calculator.
The one difference that matters
- Traditional: you contribute before income tax. You get a deduction (or exclusion) now, the money grows tax-deferred, and withdrawals in retirement are taxed as ordinary income.
- Roth: you contribute after income tax. There is no deduction now, the money grows, and qualified withdrawals in retirement are tax-free.
Everything else follows from that. Traditional gives you the tax break today and a tax bill later. Roth reverses it.
2026 limits
According to the IRS announcement for 2026:
| Account | 2026 limit |
|---|---|
| 401(k), 403(b), most 457 (traditional and Roth combined) | $24,500 employee deferrals |
| Catch-up, age 50 and over | $8,000 (and $11,250 for ages 60 to 63 where the plan allows) |
| IRA (traditional and Roth combined) | $7,500 |
| IRA catch-up, age 50 and over | $1,100 |
The IRA limit is shared between traditional and Roth IRAs: you can split $7,500 between them but not exceed it in total. The 401(k) limit is also shared between traditional and Roth 401(k) contributions.
Income limits
A Roth IRA has income limits. For 2026, the ability to contribute phases out between:
- $153,000 and $168,000 for single filers and heads of household
- $242,000 and $252,000 for married couples filing jointly
Above the top of the range, you cannot contribute directly. There is no income limit on Roth 401(k) contributions if your plan offers them.
For a traditional IRA, anyone with earned income can contribute, but the deduction phases out if you are covered by a workplace plan. For 2026, that range is $81,000 to $91,000 for single filers and $129,000 to $149,000 for married couples filing jointly (when the contributing spouse is covered by a workplace plan).
A worked comparison
To compare fairly, assume you have $10,000 of pre-tax income to save, a current marginal tax rate of 22%, and 30 years at a 7% return (an illustration, not a forecast). Growth factor over 30 years: 1.07^30 ≈ 7.61.
Traditional: you contribute the full $10,000 pre-tax. After 30 years: 10,000 × 7.61 = $76,123 before tax. You then pay income tax when you withdraw it.
Roth: the same $10,000 of pre-tax income is only $7,800 after a 22% tax, so you contribute $7,800. After 30 years: 7,800 × 7.61 = $59,376, all yours, tax-free.
The winner depends on your tax rate in retirement:
| Tax rate at withdrawal | Traditional, after tax | Roth |
|---|---|---|
| 12% | $66,988 | $59,376 |
| 22% | $59,376 | $59,376 |
| 32% | $51,763 | $59,376 |
The rule of thumb that falls out of the arithmetic:
- If your tax rate in retirement will be lower than now, traditional comes out ahead.
- If it will be the same, the two are equal.
- If it will be higher, Roth comes out ahead.
Things the simple rule leaves out
You cannot know your future rate. Tax laws change, and your income in retirement depends on pensions, Social Security, other savings and where you live.
Early career, lower income. Many younger workers are in a low bracket now and expect higher earnings later, which favors Roth.
High earners. If you are in a high bracket now and expect lower income in retirement, traditional usually favors you.
Tax diversification. Having both types gives flexibility in retirement to manage your taxable income each year.
Required minimum distributions. Traditional accounts require withdrawals starting at a certain age. Roth IRAs do not require withdrawals during the owner's lifetime.
The match. An employer 401(k) match has usually been made on a pre-tax basis even when you contribute Roth, so it adds to a traditional balance, although some plans now offer a Roth match. Check how yours works. See how the employer match works.
State taxes. If you plan to retire in a state with no income tax, traditional becomes more attractive; if you expect to move to a high-tax state, the opposite can be true.
The paycheck effect. A traditional contribution reduces your take-home pay by less than the contribution, because it lowers your tax now. A Roth contribution reduces it dollar for dollar. See how to read your paycheck.
A simple decision guide
- Get the full employer match first, whichever type you pick.
- If you are in the 10% or 12% bracket, Roth is often attractive.
- If you are in the 24% bracket or above, traditional is often attractive, especially if you expect lower income later.
- If unsure, split between both.
- Check the IRA income limits before you choose a Roth IRA.
- Review each year, since your income and the rules change.
Quick answers
Can I contribute to both a 401(k) and an IRA? Yes, subject to each limit and the IRA income rules.
What if my income is too high for a Roth IRA? Some people use a "backdoor" Roth conversion, which has its own tax rules. Speak to a tax professional.
Can I withdraw Roth contributions early? Contributions to a Roth IRA can generally be withdrawn without tax or penalty, but earnings are subject to rules. Check the details before relying on this.
Do the limits change every year? Yes, they are adjusted for inflation.
How we checked these numbers
We read the 2026 limits and income ranges from the IRS announcement, then recalculated the comparison with a script. If a figure changes or you find a mismatch with the IRS, tell us through the contact page.
This article is general information and an illustration of the arithmetic, not tax or investment advice. Consult a qualified professional about your situation.