Key facts
- There is no income limit on Roth conversions (unlike Roth IRA contributions, which phase out at $246,000 MFJ MAGI in 2026).
- Conversion amounts are taxed as ordinary income in the year converted — no 10% early-withdrawal penalty applies if the funds stay in the Roth.
- The 5-year rule: each conversion has its own 5-year holding period before earnings can be withdrawn tax-free, even after age 59½.
- IRMAA brackets apply to conversion years — a large conversion can spike Medicare Part B/D premiums two years later.
- The OBBBA (July 2025) bumped the standard deduction to $32,200 (MFJ 65+), creating more room to convert at the 12% bracket.
- The 22% bracket extends to $206,700 (MFJ taxable) and 24% to $394,600 in 2026 — these "fill up the bracket" boundaries are where most strategic conversions happen.
- Roth IRAs no longer require RMDs during the owner's lifetime as of 2024 (SECURE 2.0).
Common follow-up questions
When is the best time to do a Roth conversion?
The conversion window between retirement and age 75 (RMD start) is usually the best — earned income drops, you control how much taxable income to recognize, and you have years of tax-free growth ahead. A bear market year is also opportunistic, since you're converting depressed values.
What is the break-even point on a Roth conversion?
For a conversion in the 22% bracket assuming the same future bracket and 6% growth, break-even is approximately year 12. If your future bracket is higher than your conversion bracket, break-even shrinks dramatically (often year 4–6). If lower, you may never break even — model both scenarios before converting.
How does a Roth conversion affect IRMAA?
A large conversion raises your MAGI in the conversion year, which determines Medicare Part B and Part D premiums two years later. Crossing the $212,000 (MFJ) or $106,000 (single) threshold in 2026 adds roughly $1,000–$5,000 in Medicare costs depending on the tier. Most planners convert just below an IRMAA cliff each year.
Can I undo a Roth conversion?
No — recharacterization of conversions was eliminated by the 2017 Tax Cuts and Jobs Act. Once you convert, it's permanent. This makes the size of the conversion much more important to get right the first time.
Should I do one big conversion or many small ones?
Many small ones, almost always. A series of partial conversions filling specific brackets each year (e.g. converting up to the top of the 22% bracket) usually produces a lower lifetime tax bill than one large conversion that pushes you into 32%+ for one year.
When this doesn't apply
Roth conversion math depends heavily on your future bracket assumption — if you expect lower retirement income or you live in a no-tax state, the case weakens. People with non-deductible IRA basis must apply the pro-rata rule across all traditional IRA balances.
Disclaimer: This calculator is for educational and informational purposes only and does not constitute financial, tax, or investment advice. Results are estimates based on the assumptions and inputs provided and are not guaranteed. Actual outcomes may vary. Consult with a qualified financial advisor or tax professional before making any financial decisions.