Traditional vs Roth: Which Saves More After Tax?

Last updated: July 16, 2026

Traditional vs Roth: Which Retirement Account Wins

You're 28, earning $70,000, and your 401(k) enrollment form asks: Traditional or Roth? You pick Traditional because the tax deduction sounds good now. Twenty years later, your income has tripled, tax rates have risen, and you realize you locked in a 22% deduction to pay 35% in retirement. That choice cost you tens of thousands.

The Traditional vs Roth decision comes down to one question: will your tax rate be higher now or in retirement? Traditional contributions reduce your taxes today but are taxed as ordinary income when you withdraw. Roth contributions are taxed upfront, but withdrawals are completely tax-free—including decades of investment growth.

This calculator compares the after-tax value of each strategy based on your current rate, expected retirement rate, contribution amount, and time horizon. If rates are equal, the math is identical. The advantage comes from correctly predicting which direction rates will move.

This tool spans the Traditional-versus-Roth choice across both a 401(k) and an IRA and shows the long-term tax impact of each; if you're only choosing between a Roth and a Traditional IRA and want the break-even rate and after-tax winner for that one account, use the Roth vs Traditional IRA calculator.

Traditional vs Roth Side-by-Side

Quick Decision Rules

• Choose Roth if: You're early in your career (lower brackets), expect income growth, believe tax rates will rise, want tax-free withdrawals in retirement, or want to avoid RMDs. Roth locks in today's known tax rate.
• Choose Traditional if: You're in your peak earning years (32%+ bracket), expect lower retirement income, plan to retire in a no-income-tax state, or need the tax deduction now to afford max contributions.
• Consider both (tax diversification): Splitting between Traditional and Roth gives you flexibility to manage taxable income in retirement. Your employer match goes Traditional anyway, so Roth contributions balance that out.
• Red flag: Don't assume retirement tax rates are always lower. Social Security, pensions, RMDs, and investment income can push retirees into higher brackets than expected.

Two Comparison Scenarios

Example 1: Early Career, Expecting Income Growth

Situation: Alex is 27, earns $55,000, and sits in the 22% federal bracket. She expects to retire on $120,000 or more a year, which puts her at 24% or higher. She has $10,000 of pre-tax income to direct toward retirement each year for 35 years, and she assumes a 7% return. The honest comparison holds that $10,000 pre-tax budget constant across both accounts.

Result: Roth wins by about $27,000 ($1,078,000 versus $1,051,000 after tax). The edge is small because the rate spread is small. Two points of rate difference, applied to the same pre-tax budget, is worth a few percent. It is not worth hundreds of thousands. The common way to get a giant number here is to grow both accounts to the identical $1,382,000 and forget that the Roth dollar was already taxed down to $7,800 before it ever started compounding. Do that and Roth looks like it wins by $331,000. It doesn't. Once you tax the Roth contribution correctly, Alex's edge is roughly $27,000, and every dollar of it comes from paying 22% now instead of 24% later.

Example 2: Peak Earner, Planning to Retire Modestly

Situation: David is 52, earns $250,000, and is in the 35% federal bracket. He plans to retire at 62 with ~$80,000 annual spending (22% bracket). He can contribute $30,500 (with catch-up) for 10 years at 6% return.

Result: Traditional wins because David deducts at 35% and withdraws at 22%, a 13-point rate arbitrage.

New for 2026: High Earners Have to Make Catch-Up Contributions Roth

If you're 50 or older and you earned more than $150,000 in Social Security wages (that's Box 3 of your W-2) in 2025 from the employer whose plan you're in, a rule lands in 2026 that takes a choice away from you. Your catch-up contributions for 2026 have to go in as Roth. You can't make them pre-tax anymore. This comes from the SECURE 2.0 Act, and 2026 is the first year the IRS enforces it.

A few details decide whether it actually hits you. The $150,000 is measured on the prior year's wages, so your 2025 pay governs how your 2026 catch-up is treated. It's tied to the specific employer sponsoring the plan, not your combined income across jobs. And it only touches the catch-up portion, which is $8,000 for 2026 (or $11,250 if you're between 60 and 63). Your regular $24,500 deferral is untouched, and IRAs are out of scope entirely.

For most people caught by this, it isn't much of a loss. At that income, paying tax now on the catch-up slice and letting it grow tax-free often works out anyway, which is the Roth case. What you give up is the pre-tax deduction on that $8,000, and in a 32% or 35% bracket that stings. Plan your withholding around it. Check your own situation against the IRS catch-up contribution guidance before you set your 2026 elections.

How This Calculator Works

We project both Traditional and Roth outcomes using the same pre-tax contribution amount. For Traditional, the full amount grows tax-deferred, then we apply your retirement tax rate at withdrawal. For Roth, we reduce the contribution by your current tax rate (since it's after-tax), grow it tax-free, and show the full balance as spendable.

What we include: Federal marginal rates, compound growth over your time horizon, and after-tax final values for direct comparison. The contribution and income limits on this page are the 2026 figures, meaning the caps that apply to money you put in during calendar year 2026, sourced from IRS Notice 2025-67.

What we don't include: State taxes (though you can add them to your rate inputs), RMD impacts, Social Security taxation, IRMAA Medicare surcharges, or employer match (which always goes Traditional). This is a simplified comparison—consult a financial advisor for complex scenarios.