401(k) vs Roth IRA: which comes first?
The one difference that drives everything: when you pay tax
A traditional 401(k) and a Roth IRA are both retirement accounts that let your investments grow without yearly tax on dividends or gains.
The headline difference is timing: a traditional 401(k) is funded with pre-tax money — you skip tax now and pay it on withdrawals in retirement — while a Roth IRA is funded with after-tax money, so you pay tax now and every qualified withdrawal later is completely tax-free.
That single choice — pay tax now or pay it later — is the whole game. A 401(k) is most valuable when your tax rate today is higher than it will be in retirement; a Roth wins when your rate today is lower than you expect it to be later, which is why Roth contributions are so often recommended for younger savers and anyone early in their career.
Contribution limits in 2026
The two accounts live under separate IRS limits, so you can use both in the same year. For 2026 you can defer up to $24,500 of your salary into a 401(k), rising to $32,500 if you are 50 or older (an $8,000 catch-up), with a special higher catch-up for ages 60–63 under the SECURE 2.0 law. A Roth IRA is capped far lower at $7,500 ($8,600 if you are 50 or older).
Because the 401(k) limit is more than three times the Roth limit, the 401(k) is where serious tax-advantaged volume happens — but the Roth’s tax-free growth makes every one of its smaller dollars work harder. Model how decades of contributions and growth stack up in each with the 401(k) calculator and the Roth IRA calculator.
The tiebreaker the math can’t beat: the employer match
Before comparing tax treatment at all, look at whether your 401(k) comes with an employer match. If your employer matches 50% of contributions up to 6% of pay, that is an instant 50% return on those dollars — a guaranteed gain no Roth, index fund or savings account can match. Skipping it to fund a Roth first means leaving free money on the table.
This is why almost every "which first?" answer starts the same way: contribute enough to the 401(k) to capture the full match, then decide where the next dollar goes. The match isn’t a tax question — it’s simply the highest-return move available to most workers.
Watch the Roth income limits
Unlike the 401(k), the Roth IRA has income limits. For 2026 the ability to contribute phases out between $153,000 and $168,000 of modified adjusted gross income for single filers, and between $242,000 and $252,000 for married couples filing jointly — above the top of each range you can’t contribute directly at all.
High earners who are phased out often use a "backdoor Roth" (a non-deductible IRA contribution converted to Roth) or simply lean harder on the 401(k), which has no income cap. A 401(k) also accepts far more money, so for high incomes it usually does the heavy lifting while the Roth fills in tax-free growth where the rules allow.
A simple order of operations
For most people the two accounts aren’t an either/or — they’re a sequence: (1) contribute to the 401(k) up to the full employer match; (2) clear high-interest debt such as credit cards, where paying off the balance beats any market return; (3) max out a Roth IRA for its tax-free growth; (4) go back and push the 401(k) toward its annual limit; (5) invest anything left in a taxable brokerage account.
No employer match? Then a Roth IRA usually deserves the first dollar, because tax-free growth beats a tax deferral when there’s no match to chase. Either way, the point is to use both buckets over time rather than agonising over a single "winner". See how a few extra years of compounding changes the outcome with the compound interest calculator.
A quick way to choose today’s dollar
When you genuinely have to pick one for the next contribution, ask a single question: is my tax rate likely higher now or in retirement? Early-career, lower-bracket, or expecting a bigger income later — favour the Roth and lock in today’s low rate forever. Peak earning years in a high bracket, expecting to drop in retirement — favour the pre-tax 401(k) and take the deduction now.
Unsure? Splitting contributions between the two is a perfectly rational hedge against not knowing future tax rates — many savers deliberately build both a pre-tax and a tax-free pot so they can manage their taxable income in retirement. Run your own numbers in the 401(k) and Roth IRA calculators to see the gap in real dollars.