A Roth IRA and a 401(k) are different tools for different circumstances, not one better choice for everyone

Whether a Roth IRA works better than a 401(k) depends on your current income, your employer, and what tax bracket you expect to be in during retirement. A Roth IRA lets you contribute after-tax money now and withdraw it tax-free later. A 401(k) lets you contribute before-tax money now, which lowers your taxes today, but you pay taxes on withdrawals later. Neither is universally better — many people use both.

The real question is not which one to choose, but whether you have access to each one, how much you can contribute to each, and which tax treatment makes sense for your situation right now.

Key Takeaways

  • A 401(k) requires an employer to offer it; a Roth IRA you can open on your own if you have earned income and meet income limits.
  • A 401(k) reduces your taxes this year; a Roth IRA reduces your taxes in retirement, which matters more if you expect higher income later.
  • A 401(k) often includes employer matching money, which is immediate return on your contribution and usually not available with a Roth IRA.
  • Contribution limits are higher for a 401(k) than a Roth IRA, so if you want to save more, a 401(k) gives you more room.
  • You can have both at the same time, and many people do — the choice is not either/or.

When a 401(k) makes more sense

A 401(k) is the better starting point if your employer offers one and matches contributions. Employer matching is money your employer adds to your account based on what you contribute — usually 50 cents to a dollar for every dollar you put in, up to a certain percentage of your salary. That is immediate return on your money, and it does not exist in a Roth IRA. If your employer matches, contribute enough to get the full match before you consider anything else.

A 401(k) also makes sense if you have high income this year and want to lower your taxes now. When you contribute to a 401(k), that money comes out of your paycheck before taxes are calculated, so your taxable income drops. If you are in a high tax bracket right now, that tax cut is real money in your pocket this year. A Roth IRA does not give you that benefit — you pay taxes on the money before you contribute it.

A 401(k) is also your only option if your income is too high for a Roth IRA. Roth IRA contributions are limited or blocked entirely if your income exceeds certain thresholds, which vary by year and filing status. A 401(k) has no income limit.

When a Roth IRA makes more sense

A Roth IRA is the better choice if you are early in your career, earning less now than you expect to earn later. Because you pay taxes on the money before you contribute it, you pay at your current (lower) tax rate. When you retire and withdraw the money, you owe no taxes at all — even though the account may have grown significantly. If you expect to be in a higher tax bracket in retirement, a Roth IRA saves you money over your lifetime.

A Roth IRA also makes sense if you want flexibility. You can withdraw contributions (not earnings) at any time without penalty, even before retirement. A 401(k) charges a 10 percent penalty plus taxes if you withdraw before age 59½, with limited exceptions. If you think you might need access to your money before retirement, a Roth IRA is more forgiving.

A Roth IRA is also useful if you do not have an employer 401(k) available. Self-employed people, gig workers, and employees of small companies without retirement plans can open a Roth IRA on their own. You do not need anyone's permission or involvement.

Contribution limits and how much you can save

A 401(k) allows much larger contributions than a Roth IRA. For 2024, you can contribute up to $23,500 to a 401(k) if you are under 50, and $31,000 if you are 50 or older. A Roth IRA allows $7,000 if you are under 50, and $8,000 if you are 50 or older. If you want to save aggressively for retirement, a 401(k) gives you more than three times the annual room.

These limits change each year, and the IRS announces new limits in October for the following year. Check the IRS website or your plan documents for the current year's limits.

Income limits and who can contribute

A 401(k) has no income limit. Anyone whose employer offers one can contribute, regardless of how much they earn.

A Roth IRA has income phase-out ranges. If your income exceeds a certain threshold, you cannot contribute the full amount, and above a higher threshold, you cannot contribute at all. These thresholds depend on your filing status (single, married filing jointly, married filing separately) and change each year. For 2024, the phase-out for single filers starts at $146,000 and ends at $161,000. For married filing jointly, it starts at $230,000 and ends at $240,000. If your income is above these ranges, you cannot contribute to a Roth IRA directly, though other strategies exist.

Taxes now versus taxes later

The core difference is timing. A 401(k) is a tax deferral: you skip taxes now and pay them later. A Roth IRA is tax-free growth: you pay taxes now and never pay them again on that money or its earnings.

Which is better depends on whether you think tax rates will be higher or lower in retirement than they are now. If you expect to earn less in retirement (and thus be in a lower tax bracket), a 401(k) makes sense — you pay taxes at a lower rate later. If you expect to earn the same or more, or if you think tax rates will rise overall, a Roth IRA makes sense — you lock in today's rate and pay nothing later.

Most people cannot predict their retirement income with certainty, which is why many use both: a 401(k) for the immediate tax cut and employer match, and a Roth IRA for tax-free growth on additional savings.

Using both at the same time

You can contribute to a 401(k) and a Roth IRA in the same year. There is no rule against it. Many people do this: they contribute to their employer's 401(k) to get the match and lower their current taxes, then contribute to a Roth IRA with additional savings to build tax-free retirement income.

The only limit is your total earned income. You cannot contribute more than you earned in a given year across all retirement accounts combined. If you earned $50,000, you cannot put $23,500 in a 401(k) and $7,000 in a Roth IRA — your total contributions cannot exceed your earnings.

Frequently Asked Questions

Can I move money from a 401(k) to a Roth IRA?

Yes, through a process called a Roth conversion. You withdraw money from your 401(k) and deposit it into a Roth IRA. You pay taxes on the amount you convert in the year you do it, but the money then grows tax-free in the Roth. This strategy makes sense if you expect your tax rate to be higher later, or if you have a 401(k) with high fees and want to move it to a lower-cost Roth IRA. Consult a tax professional before converting, because the tax bill can be substantial.

What happens to my 401(k) if I leave my job?

You keep the money, but you cannot contribute to that 401(k) anymore. You can leave it where it is, roll it into your new employer's 401(k) if they offer one, or roll it into a traditional IRA. A Roth IRA stays with you regardless of employment, so you can keep contributing as long as you have earned income and meet income limits.

Which account should I fund first?

If your employer offers a 401(k) match, contribute enough to get the full match first — that is assistance programs. Then, if you have more to save and meet Roth IRA income limits, contribute to a Roth IRA. After that, go back to your 401(k) and contribute more if you want. This order maximizes employer matching and gives you tax-free growth in the Roth.

Do I have to withdraw money from my accounts at a certain age?

Yes, but the rules differ. A 401(k) requires withdrawals starting at age 73 (as of 2023; this age changes over time). A Roth IRA does not require withdrawals during your lifetime — you can leave the money untouched and pass it to heirs. This makes a Roth IRA useful if you do not need the money in retirement and want to leave a tax-free inheritance.