If you have a few hundred dollars a month to invest and both a Roth IRA and a 401(k) available, the question isn't really "which one is better" — it's "which one first, and how much." Each account has a distinct tax treatment, contribution limit, and set of rules, and using them in the right order can add hundreds of thousands of dollars to your retirement over a career. This 2026 guide breaks down the tradeoffs, the new contribution limits, and a simple priority list, with a note for Canadian readers on the RRSP and TFSA equivalents.
Before we dive in, it helps to see the long-term impact of starting now. Our retirement calculator lets you project how today's contributions grow into a nest egg over the decades.
The Core Difference: When You Pay Tax
Both accounts let your investments grow without yearly taxes on gains. The difference is timing:
- Traditional 401(k): Contributions come out of your paycheck before tax, lowering this year's taxable income. You pay ordinary income tax when you withdraw in retirement.
- Roth IRA: Contributions are made with after-tax dollars, so there's no deduction today, but qualified withdrawals in retirement — including all the growth — are completely tax-free.
The simplest way to think about it: a 401(k) bets your tax rate will be lower in retirement, while a Roth bets it'll be the same or higher. Since most people can't predict tax law decades out, holding both is a legitimate hedge.
2026 Contribution Limits
The IRS raised several limits for 2026, and there's a notable new rule for people in their early sixties:
- 401(k): $24,500 employee contribution limit. Catch-up of $8,000 for ages 50+. New for 2026: a "super catch-up" of $11,250 for ages 60-63, raising their total to $35,750.
- Roth IRA: $7,500 limit, plus a $1,100 catch-up for ages 50+. Eligibility phases out at higher incomes — roughly starting around $150,000 for single filers and $236,000 for married filing jointly in 2026.
Note that 401(k)s have no income limit on participation, which is why high earners who are phased out of a Roth IRA often look at a 401(k) Roth option or a backdoor Roth strategy.
The Employer Match Comes First — Always
If your employer matches 401(k) contributions, that match is the highest-return investment you'll ever make. A common 50% match on the first 6% of pay is an instant 50% return before the market does anything. A dollar-for-dollar match is a 100% return. No Roth IRA, index fund, or stock pick reliably beats free money.
So the universal first step is: contribute at least enough to your 401(k) to capture the full match. Leaving match dollars on the table is the most common avoidable mistake in retirement saving. Use the investment calculator to see how even a modest matched contribution snowballs over 30 years.
A Simple Order of Operations for 2026
For most US savers, this priority list works well:
- 1. 401(k) up to the full match — capture every matched dollar.
- 2. Roth IRA up to $7,500 — tax-free growth, broad investment choices, and flexible early access to contributions.
- 3. Back to the 401(k) — keep filling toward the $24,500 limit for the tax break and high ceiling.
- 4. Taxable brokerage or HSA — once tax-advantaged space is maxed, invest the rest.
Why slot the Roth IRA second rather than the 401(k)? An IRA usually offers far more investment options and lower fees than a typical employer plan, and Roth contributions (not earnings) can be withdrawn anytime without penalty, giving you a built-in backstop.
The Power of Starting Early
The single biggest variable in your retirement balance isn't which account you pick — it's how long your money compounds. Thirty dollars a week invested from age 25 can outgrow far larger contributions started at 45, simply because of decades of reinvested growth. See the effect for yourself with the compound interest calculator; the gap between starting today and waiting five years is often shocking.
This is also why you shouldn't agonize over the Roth-vs-traditional decision so long that you delay investing. A "good enough" choice made today almost always beats the "perfect" choice made next year.
What About Canadian Readers?
Canada has close cousins to these accounts. The RRSP mirrors a traditional 401(k): contributions are tax-deductible and withdrawals are taxed later, with room equal to 18% of prior-year income up to an annual maximum. The TFSA mirrors a Roth: contributions aren't deductible, but all growth and withdrawals are tax-free, with a 2026 contribution limit of $7,000. The same logic applies — capture any employer group RRSP match first, then weigh RRSP versus TFSA based on whether your tax rate is higher now or expected to be higher later. Lower earners often favor the TFSA; higher earners frequently lean RRSP for the upfront deduction.
Related Calculators
- Retirement Calculator — project your nest egg from today's savings rate.
- Investment Calculator — model contributions, returns, and the employer match.
- Compound Interest Calculator — see why starting early matters so much.
Frequently Asked Questions
What are the 2026 contribution limits for a 401(k) and Roth IRA?
In 2026 you can contribute up to $24,500 to a 401(k), plus a $8,000 catch-up at age 50 and older, with a new higher catch-up of $11,250 for ages 60-63. The Roth IRA limit is $7,500, plus a $1,100 catch-up at 50 and older, subject to income phase-outs.
Should I fund my Roth IRA or 401(k) first?
Contribute enough to your 401(k) to capture the full employer match first, because that match is an instant 50%-100% return. After the match, many savers prioritize a Roth IRA for its tax-free growth and flexible withdrawals, then return to the 401(k) to use the rest of the higher limit.
Is a Roth or traditional account better for taxes?
Roth accounts use after-tax money and grow tax-free, which wins if you expect higher tax rates in retirement. Traditional accounts give an upfront deduction and are taxed on withdrawal, which wins if your rate will be lower later. Many people split between both to hedge against unknown future tax rates.
What are the Canadian equivalents of the 401(k) and Roth IRA?
In Canada, the RRSP works like a traditional 401(k) with tax-deferred contributions, and the TFSA works like a Roth with tax-free growth and withdrawals. The 2026 TFSA limit is $7,000 and RRSP room is 18% of prior-year income up to an annual maximum.