Roth vs. Traditional 401(k): Which Should You Choose?
Most 401(k) plans now offer a choice between Roth and Traditional contributions. The decision comes down to a single underlying question: do you want to pay taxes now, or later? The answer depends less on which account "performs better" — the underlying investments are identical — and more on how your tax rate now compares to your expected tax rate in retirement.
The Tax Mechanics
Traditional 401(k) contributions are deducted from your paycheck before income tax is applied, lowering your taxable income today. When you withdraw in retirement, the full withdrawal — contributions and growth — is taxed as ordinary income.
Roth 401(k) contributions are made with money that's already been taxed. There's no deduction today, but qualified withdrawals in retirement, including all the growth, are completely tax-free.
When Traditional Wins
If you're in a high tax bracket now and expect a meaningfully lower bracket in retirement — a common pattern, since many retirees have lower income than during their working years — Traditional lets you take the deduction while your rate is high and pay tax later while your rate is lower.
When Roth Wins
If you're early in your career with a relatively low current tax rate, or you expect tax rates in general to rise, or you simply want the certainty of tax-free withdrawals regardless of what future tax law does, Roth can come out ahead. Younger workers in particular often favor Roth since their current rate is already low.
Splitting the Difference
Many people can't predict their future tax bracket with confidence, and splitting contributions between Roth and Traditional is a reasonable hedge — you get some of each tax treatment, reducing the cost of guessing wrong in either direction.
Frequently Asked Questions
What's the basic difference between Roth and Traditional 401(k)?
Traditional contributions are made pre-tax and taxed on withdrawal in retirement. Roth contributions are made after-tax and withdrawals in retirement are tax-free.
When is Traditional the better choice?
Traditional tends to be better when you expect your tax rate in retirement to be lower than your current tax rate, since you defer taxation to a lower-rate period.
When is Roth the better choice?
Roth tends to be better when you expect your tax rate in retirement to be the same or higher than now, since you lock in today's rate on contributions and pay nothing later.
Can I contribute to both in the same year?
Yes. Many plans allow splitting contributions between Roth and Traditional, which can hedge against uncertainty about future tax rates.
Does employer match go into Roth or Traditional?
Employer match is generally deposited pre-tax regardless of which type you choose for your own contributions, though some newer plans allow Roth matching as well.
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