Roth Conversion Tax Bracket Calculator (2026)

Is there an annual limit on how much I can convert to a Roth IRA?

No. Unlike Roth IRA contributions (capped at $7,000 for those under 50 and $8,000 for those 50+ in 2026 per IRS Notice 2025-67), Roth conversions have no IRS annual dollar limit. You could convert your entire traditional IRA balance in a single year. The practical ceilings are your tax bracket top, IRMAA surcharge thresholds, ACA subsidy cliff for pre-Medicare retirees, and Social Security taxation phase-ins. Most retirees fill the 22% or 24% bracket each year over a multi-year conversion window.

What is the 22% tax bracket for married couples filing jointly in 2026?

For married filing jointly, the 22% bracket covers taxable income from $100,800 to $211,400 (IRS Rev. Proc. 2025-32). With the 2026 standard deduction of $32,200 ($35,500 if both spouses are 65+), a couple's 22% bracket window spans roughly $133,000 to $243,600 in total gross income before the Roth conversion. The calculator above computes the exact conversion room for your specific income and deduction situation.

Should I fill the 22% or 24% bracket with Roth conversions?

The 22% bracket is the classic golden-window target: you lock in a 22% rate now versus the 32–37% most retirees face when RMDs force withdrawals starting at age 73 or 75. The 24% bracket makes sense if your projected post-RMD rate is 32%+ — common for couples with large IRA balances where RMDs plus Social Security push income well into higher brackets. An 8-point spread (24% now vs. 32% later) still justifies the higher current tax. If your future rate is only 28–30%, the 22% bracket is usually the better target.

Does a Roth conversion count toward Medicare IRMAA surcharges?

Yes. Every converted dollar adds to your Modified Adjusted Gross Income (MAGI) for IRMAA purposes, with a two-year lookback: your 2026 conversions determine your 2028 Medicare premiums. In 2026, IRMAA Tier 1 starts at $109,000 for single filers and $218,000 for married couples. Crossing Tier 1 adds approximately $1,148 per year per enrolled Medicare beneficiary in combined Part B and Part D surcharges. The calculator flags whether each bracket-filling scenario crosses a tier so you can plan around — or deliberately cross — the threshold.

How does Social Security income affect my Roth conversion tax bracket?

Social Security creates a "torpedo" effect that raises your effective marginal rate above the stated bracket. When conversion income rises in the phase-in zone ($32,000–$44,000 combined income for MFJ; $25,000–$34,000 for single filers), each $1 of conversion income triggers $0.85 in additional SS taxation, making the effective marginal rate 1.85× the bracket rate. A stated 22% bracket conversion can cost 25–28% all-in. This is not modeled here; use the Total Tax Calculator for the complete all-in picture including SS torpedo and IRMAA.

How many years does it take to convert a large IRA using annual bracket-filling?

A couple with $2 million in a traditional IRA and $60,000 in pension income might have ~$103,000/year of 22%-bracket conversion room. Dividing $2 million by $103,000 suggests roughly 19 years — but the IRA keeps growing, so front-loading conversions early in the golden window (before Social Security starts and before RMDs begin at 73 or 75) compresses the timeline and reduces lifetime taxes. The calculator estimates years of runway at the bottom of its results based on your balance and annual fill amount.