Abel's Calculators

The Core Question: Tax Rate Now vs Later

Traditional contributions are pre-tax — you deduct them from your income now and pay taxes when you withdraw in retirement. Roth contributions are after-tax — you pay taxes now and withdrawals in retirement are tax-free.

The one that builds more after-tax wealth is the one where you pay taxes at the lower rate. If your tax rate is higher now than it will be in retirement, Traditional wins. If your tax rate is lower now, Roth wins.

Most people get this wrong because they compare their current marginal rate to a vague sense of what "taxes in retirement" means. The relevant comparison is your current marginal rate (the rate on the next dollar you earn) vs your effective rate on withdrawals in retirement — which is almost always lower, because retirement income typically starts from zero and fills up the lower brackets first.

Why Traditional Usually Wins During High-Earning Years

Consider someone in the 24% federal tax bracket contributing to a Traditional 401(k). Every dollar they contribute saves 24 cents in taxes right now.

In retirement, their income picture looks different. They're no longer earning a salary or saving 20–30% of their income. Their taxable income starts at zero. The first ~$30,000 of income for a married couple filing jointly is covered by the standard deduction — taxed at 0%. The next ~$24,000 falls in the 10% bracket. The next ~$77,000 falls in the 12% bracket.

So even if they withdraw $80,000/year from their Traditional accounts, their effective federal tax rate on that income is roughly 10–12%. They saved at 24%, and they're paying at 10–12%. That's a significant net benefit for every dollar that went Traditional.

The standard deduction is what makes this especially powerful. Every retiree gets ~$30,000 (married filing jointly) of tax-free income regardless. Traditional contributions that are later withdrawn within that deduction amount are effectively never taxed at all — pre-tax going in, tax-free coming out.

The Roth Conversion Ladder

For early retirees, there's a way to get the best of both worlds: contribute Traditional during your working years (when your tax rate is high), then convert to Roth during early retirement (when your income is low or zero).

Here's how the mechanics work:

You retire at, say, 50 with most of your savings in Traditional IRA or 401(k) accounts. Between ages 50 and 67 (before Social Security begins), your earned income is low or nonexistent. During these years, you convert portions of your Traditional balance to Roth each year, strategically filling the lowest tax brackets.

For a married couple filing jointly, the math looks like this:

• Standard deduction (~$30,000): The first $30,000 you convert is taxed at 0% federal tax. It's covered entirely by the deduction.
• 10% bracket (~$24,000): The next $24,000 you convert is taxed at just 10%, costing $2,400 in federal tax.
• Total: You can convert roughly $54,000 per year at an effective federal tax rate of about 4.4%.

Compare that to the 24% marginal rate you saved at when you contributed. You saved at 24%, converted at ~4.4%, and now the money is in a Roth where it grows and can be withdrawn completely tax-free for the rest of your life.

The 5-year seasoning rule

There's one important constraint: each Roth conversion has its own 5-year clock. You must wait 5 years from January 1 of the year you converted before you can withdraw that specific converted amount penalty-free (if you're under 59½).

This means you need 5 years of living expenses accessible outside the Roth to bridge the gap. This typically comes from a taxable brokerage account, cash savings, or other accessible funds. Once the first conversion "seasons" after 5 years, each subsequent year's conversion becomes available in sequence — creating a rolling ladder of accessible funds.

When Roth Contributions Make Sense

Despite Traditional's advantage during high-earning years, there are several situations where Roth contributions are the better choice:

• You're early in your career and in a low bracket (10–12%). If you're paying 10–12% now, it's hard to imagine paying less in retirement. Lock in the low rate with Roth.
• You expect significantly higher income later. If you're in medical residency, just starting a business, or early in a high-growth career, your current low rate is temporary. Roth lets you pay taxes at today's low rate.
• Your employer match goes Traditional anyway. Since employer 401(k) matches are always pre-tax, making your own contributions Roth adds tax diversification to your retirement accounts.
• You want flexibility in retirement to manage your tax bracket. Having both Roth and Traditional accounts lets you choose which to draw from in any given year, giving you control over your taxable income.
• You're already maxing Traditional and have additional money to save. The backdoor Roth IRA lets high earners contribute to a Roth even above the income limits.

A Decision Framework

• Current marginal rate 10–12%: Roth is likely better. You're paying a low rate now that's hard to beat in retirement.
• Current marginal rate 22%: Close call. Consider splitting contributions between Roth and Traditional for tax diversification.
• Current marginal rate 24%+: Traditional usually wins, especially if you plan to do Roth conversions in retirement when your income is lower.
• Planning to retire early: Traditional + Roth conversion ladder is often the optimal strategy. Save at high rates, convert at low rates.
• Unsure: Split between Roth and Traditional. Tax diversification is a reasonable default when the math is unclear.