Roth Conversion Calculator

A Roth conversion is the process of moving money from a Traditional IRA or 401(k) into a Roth IRA. You pay ordinary income tax on the converted amount in the year of conversion, but the funds then grow tax-free and qualified withdrawals in retirement are tax-free. Unlike annual Roth IRA contributions, there is no annual limit on how much you can convert.

The right amount depends on your current income, filing status, expected tax rate in retirement, and time horizon. A common approach is the "fill the bracket" strategy — convert just enough to reach the top of your current tax bracket without spilling into the next higher rate. This maximizes the amount converted at the lowest possible marginal rate.

The fill-the-bracket strategy means converting enough to bring your total taxable income up to the top of your current tax bracket without crossing into the next rate. For example, if you are a single filer with $64,250 of taxable income and you are in the 22% bracket (which runs to $103,350 for 2025), you could convert up to $39,100 and still stay within the 22% bracket. Any additional conversion would push income into the 24% bracket.

Yes. Medicare uses your Modified Adjusted Gross Income (MAGI) from two years prior to determine your Part B and Part D premiums. A large Roth conversion can push your MAGI above IRMAA thresholds, resulting in surcharges. For 2025, IRMAA surcharges begin at $106,000 for single filers and $212,000 for married filing jointly. Plan conversions carefully if you are already enrolled in Medicare or will be within two years.

No. The Tax Cuts and Jobs Act of 2017 (TCJA) eliminated the ability to recharacterize (undo) a Roth conversion. Before 2018, you could reverse a conversion if the account lost value or your tax situation changed. That option no longer exists. Once you convert, the decision is permanent and the tax is owed for that year.

A Roth conversion is most beneficial when you expect to be in a higher tax bracket in retirement than you are today, during a low-income year (job change, early retirement, large deduction), to reduce future Required Minimum Distributions (RMDs), to leave tax-free assets to heirs, or if you expect federal or state tax rates to rise in the future.

A Roth conversion is added to your ordinary income for the tax year in which it occurs. The converted amount is taxed at your marginal federal income tax rate. There is no 10% early withdrawal penalty on the conversion itself (though earnings withdrawn before age 59½ from the Roth account may still be subject to penalties during the 5-year seasoning period). State income tax may also apply depending on where you live.

There is no annual dollar limit on Roth conversions. You can convert as much as you want from a Traditional IRA or 401(k) in a single year. However, converting large amounts at once can push you into higher tax brackets, trigger IRMAA surcharges, or increase taxation of Social Security benefits. For most people, spreading conversions over several years with a partial conversion strategy produces the best long-term outcome.