A Roth account is better if you expect your tax rate to be higher in retirement than it is today. A Traditional account is better if you expect your tax rate to drop. That’s the core math, but the real answer depends on your income, your age, how much you earn now versus how much you’ll withdraw later, and a few structural differences between the two account types that go beyond taxes.
The Tax Rate Comparison That Drives Everything
A Traditional IRA or 401(k) gives you a tax deduction today. You contribute pre-tax dollars, your money grows tax-deferred, and you pay income tax when you withdraw it in retirement. A Roth flips that sequence: you contribute after-tax dollars, your money grows tax-free, and withdrawals in retirement are completely tax-free.
If your tax rate stays exactly the same from now until retirement, the two accounts produce identical results. The real advantage comes from a rate mismatch. Say you’re in the 22% bracket today and expect to be in the 12% bracket in retirement. A Traditional account lets you dodge the 22% rate now and pay only 12% later. That’s a win. But if you’re in the 12% bracket today and expect to climb into the 24% bracket by the time you retire, a Roth lets you lock in the lower rate now and never pay taxes on that money again.
This is why age matters so much. A 25-year-old early in their career is likely earning less than they will at peak earning years or even in retirement when they’re pulling from decades of compounded growth. Paying taxes on a modest salary now, through Roth contributions, often beats paying taxes on a much larger pool of money later. A 55-year-old at peak earnings, on the other hand, may benefit more from the Traditional deduction today if their retirement income will be lower.
What Tax Rates Might Do Next
The 2017 Tax Cuts and Jobs Act lowered individual income tax rates, but many of those cuts are scheduled to expire after 2025. If Congress doesn’t extend them, most brackets will rise. The 12% bracket would jump to 15%, the 22% bracket to 25%, and the 24% bracket to 28%. The standard deduction would also shrink significantly. The Tax Foundation estimates that 62% of filers would see a tax increase if the law sunsets as written.
Nobody can predict what Congress will ultimately do, but this uncertainty is one reason many financial planners have leaned toward Roth contributions in recent years. If you lock in today’s relatively low rates through Roth contributions, you’re protected against future rate increases. If rates stay the same or fall, you haven’t lost much. That asymmetry makes the Roth side of the bet somewhat more forgiving for people in the middle brackets.
Income Limits and Eligibility
Not everyone can use both options. The IRS places income caps on Roth IRA contributions and on the tax deductibility of Traditional IRA contributions, and these limits differ.
For 2026, single filers can contribute directly to a Roth IRA only if their modified adjusted gross income is below $168,000. The contribution starts phasing out at $153,000. For married couples filing jointly, the phase-out range is $242,000 to $252,000. If you earn above those ceilings, you can’t make a direct Roth IRA contribution.
Traditional IRA deductions have their own limits, but only if you (or your spouse) are covered by a workplace retirement plan like a 401(k). For 2026, single filers covered by a workplace plan can deduct Traditional IRA contributions only if their income is below $91,000, with the deduction phasing out starting at $81,000. Married couples filing jointly phase out between $129,000 and $149,000 when the contributing spouse has a workplace plan. If neither spouse has a workplace plan, the deduction is available at any income level.
Workplace Roth 401(k) accounts have no income limit at all, which makes them accessible to high earners who can’t contribute directly to a Roth IRA.
The Backdoor Roth for High Earners
If your income exceeds the Roth IRA limits, you can still get money into a Roth through a two-step process known as a backdoor Roth conversion. You contribute to a Traditional IRA on a nondeductible basis (meaning you don’t claim a tax break), then convert that balance to a Roth. Since you already paid taxes on the contribution, the conversion itself creates little or no additional tax.
The 2026 IRA contribution limit is $7,500, or $8,600 if you’re 50 or older. You can contribute up to that amount regardless of income, then convert the full balance. You’ll report the nondeductible contribution on IRS Form 8606 when you file your taxes, and you’ll receive a Form 1099-R documenting the conversion.
There’s one important wrinkle called the pro rata rule. If you already have pre-tax money in any Traditional IRA, the IRS treats your conversion as coming proportionally from both pre-tax and after-tax funds. For example, if you have $93,000 in pre-tax Traditional IRA money and make a $7,500 nondeductible contribution, 92.5% of any conversion amount would be taxable, even if you only intended to convert the new $7,500. The cleanest way to avoid this is to roll any existing pre-tax Traditional IRA balances into your employer’s 401(k) before converting, leaving only the after-tax contribution in the IRA.
Some 401(k) plans also allow a “mega backdoor Roth,” where you make after-tax contributions beyond the standard employee deferral limit and then convert those to Roth. The total 401(k) contribution ceiling for 2026, including employee deferrals, employer matches, and after-tax contributions, is $72,000 ($80,000 if you’re 50 or older). Not all plans permit this, so you’d need to check with your employer.
Required Minimum Distributions
Traditional IRAs force you to start withdrawing money at age 73, whether you need it or not. These required minimum distributions (RMDs) are calculated based on your account balance and life expectancy, and the IRS charges a 25% excise tax on any amount you fail to withdraw on time (reduced to 10% if you correct the shortfall within two years).
Roth IRAs have no RMDs during the owner’s lifetime. Your money can stay invested and growing tax-free for as long as you live. This makes the Roth especially valuable if you don’t plan to spend down your retirement accounts quickly, or if you want to leave tax-free assets to heirs. Beneficiaries will eventually face distribution requirements, but the original owner never does.
This difference also affects your tax picture in retirement. Traditional IRA RMDs count as taxable income, which can push you into a higher bracket, increase the taxable portion of your Social Security benefits, and raise your Medicare premiums. Roth withdrawals don’t trigger any of those effects.
When a Traditional Account Wins
The Traditional approach has the clearest advantage when you’re in a high tax bracket during your working years and confident your retirement income will be lower. If you’re earning $200,000 and paying a 32% marginal rate, the immediate tax savings from a Traditional contribution are substantial. If your retirement withdrawals will fall in the 22% or 12% bracket, you come out ahead by deferring.
Traditional accounts also win if you plan to retire in a state with no income tax, since you’d avoid state taxes on withdrawals entirely. And if you need to reduce your adjusted gross income right now to qualify for other tax benefits or avoid phaseouts, the Traditional deduction can deliver value beyond the retirement math alone.
When a Roth Account Wins
The Roth has a structural advantage for younger workers, lower earners, and anyone who expects their income to grow significantly. If you’re in the 12% or 22% bracket now, paying that rate upfront is a relatively small price for decades of tax-free growth. A $7,500 Roth contribution growing at 7% annually for 30 years becomes roughly $57,000, and every dollar of that comes out tax-free.
Roth accounts also provide more flexibility before retirement. You can withdraw your original contributions (not earnings) at any time without taxes or penalties, making them a partial emergency fund. Converted amounts are subject to a five-year holding period if you’re under 59½, and earnings have their own five-year rule for tax-free withdrawal.
The absence of RMDs gives the Roth another edge for people who want to control their taxable income in retirement or who expect to leave money to the next generation. And for anyone worried about future tax rate increases, the Roth removes that uncertainty entirely.
Using Both at the Same Time
You don’t have to pick just one. Many people split contributions between Roth and Traditional accounts to create tax diversification. Having both types gives you the ability to choose which account to draw from in any given year of retirement, pulling from Traditional accounts in low-income years and Roth accounts in high-income years to manage your tax bracket.
If your employer offers both a Traditional and Roth 401(k), you can split your deferrals between them up to the combined annual limit of $24,500 in 2026 ($32,500 if you’re 50 or older). You can also contribute to an IRA on top of your 401(k). The combination of a Traditional 401(k) and a Roth IRA, or a Roth 401(k) and a Traditional IRA, gives you tax diversification without requiring you to predict the future.