When should you do a Roth conversion?

A Roth conversion moves money from a traditional IRA or other pre-tax retirement account into a Roth IRA. You pay income tax on the converted amount in the year of the conversion; in exchange, qualified Roth withdrawals in retirement can be tax-free, including all future growth. There is no income limit on conversions — which is why high earners use conversions for backdoor Roth strategies. The question is not whether conversions are allowed, but whether paying tax today buys enough future benefit to justify the cost.

What triggers tax on a conversion?

The converted amount is generally included in your taxable income for the year. If you convert $50,000 and your marginal federal rate is 22%, the conversion might add roughly $11,000 in federal tax — plus state tax where applicable. The IRS treats the conversion as ordinary income, not capital gains.^[1] Partial conversions are allowed; converting $10,000 per year over five years can fill lower tax brackets without jumping into a higher one all at once.

Paying the tax from outside the IRA — checking or taxable brokerage — keeps the full converted amount working in the Roth. Withholding tax from the conversion itself reduces what reaches the Roth and usually hurts long-term results.

Estimate federal tax and project retirement values with the Roth conversion calculator. Compare account types first in the Roth vs. traditional IRA calculator.

When conversions tend to make sense

• Low-income years — sabbatical, early retirement before Social Security and RMDs, or a year with large deductions
• Early career — marginal rates are lower now than you expect in peak earning years or retirement
• RMD reduction — shrinking traditional balances before age 73 lowers future required distributions^[3]
• Tax diversification — building Roth assets alongside traditional balances for flexible retirement income^[4]
• Estate planning — Roth accounts pass tax-free growth to beneficiaries (with SECURE Act distribution rules)

Conversions make less sense when you are in a high bracket now and expect lower taxable income in retirement, when you cannot pay the tax without draining other savings, or when the conversion pushes you into Medicare IRMAA surcharges or reduces ACA premium tax credits — effects this site's calculator does not model.

Partial conversions and bracket filling

A common strategy converts just enough each year to "fill" the 12% or 22% federal bracket without spilling into the next tier. Spread over five to ten years, partial conversions can move a large traditional balance to Roth while keeping annual tax manageable. Coordinate with other income — capital gains, Roth 401(k) withdrawals, or Required Minimum Distributions once they begin.

Model RMD pressure with the RMD calculator and sustainable spending with the safe retirement withdrawals guide.

Backdoor Roth and pro-rata rules

Direct Roth IRA contributions phase out at higher incomes, but conversions have no income cap. A backdoor Roth involves making a non-deductible traditional IRA contribution and converting it to Roth shortly after. If you hold other pre-tax IRA balances, the IRS pro-rata rule taxes conversions proportionally — much of the conversion may be taxable even if you just contributed after-tax dollars.^[1] Some planners roll pre-tax IRA money into a 401(k) that accepts rollovers to clear the pro-rata calculation before converting.

Five-year rule and access

Converted amounts have their own five-year clock for penalty-free access to conversion principal before age 59½. Each conversion year starts a new five-year period. Earnings on conversions follow Roth qualified distribution rules.^[2] This matters mainly for early retirees; most conversions are planned for long-term tax-free growth, not near-term withdrawals.

Roth conversion vs. leaving money traditional

Leaving money in a traditional IRA defers tax but creates future taxable income and RMDs. Converting pays tax now to eliminate future tax on growth and qualified withdrawals. The break-even depends on how many years the Roth compounds, the tax rate paid at conversion vs. expected withdrawal rates, and whether RMDs would have forced withdrawals you did not need. Our Roth vs. traditional IRA guide covers the broader account-type decision; conversions are the tool for changing types after money is already pre-tax.

Before you convert

1. Estimate total tax cost including state taxes and surcharges
2. Confirm cash to pay tax without selling investments at a loss unnecessarily
3. Check pro-rata impact if you hold multiple IRA balances
4. Consider multi-year partial conversion schedule
5. Document the conversion for tax filing — Form 8606 if nondeductible basis involved

Large conversions are irreversible for tax purposes in most cases — treat the decision as a planning exercise, not a year-end impulse. Consult a tax professional when conversions interact with business income, AMT, or complex IRA basis tracking.