You stop working at the end of 2030 and Social Security starts at 70, so 2031–2033 are your lowest-income years. This compares how much of the pre-tax IRA to convert to Roth each year in that window. All figures are in today's dollars, with tax brackets assumed to rise with inflation. Educational model, not tax advice — run final numbers with a CPA before converting.
Tap a row to see its year-by-year detail. "Advantage" = after-tax wealth at the horizon versus converting nothing, counting taxes and Medicare surcharges paid along the way.
Tax rules (2026 values, indexed): federal MFJ brackets (12% to $100,800, 22% to $211,400 taxable), $32,200 standard deduction + $1,650 per spouse 65+; long-term gains 0% up to $98,900 of total taxable income; Social Security taxed up to 85% using the $32K/$44K thresholds (not indexed); NIIT 3.8% above $250K. Maine: 5.8 / 6.75 / 7.15%, Social Security exempt, $5,150 exemption per person, pension deduction ≈ $48,216 minus your Social Security (so your $12K pension is Maine-free until 70). Conversions are treated as fully Maine-taxable — check whether Maine's pension deduction can shelter part of a conversion.
Why gains matter: conversions stack under your capital gains. Up to the 0% line, a conversion dollar costs about 12% federal. Past it, each converted dollar also pushes a dollar of gains from 0% to 15%, so the federal cost jumps to ~27% until all gains are pushed over. If 2031–33 spending comes from cash or a Treasury ladder instead of selling appreciated stock, more converts cheaply.
RMDs start at 75 (born 1963) using the IRS Uniform Lifetime Table. IRMAA uses income from two years earlier; 2026 thresholds start at $218K MAGI (MFJ) and $109K (single).
Survivor: the surviving spouse keeps the larger Social Security benefit ($54,300) and files single brackets from the age you set. Taxes on conversions are paid from taxable money (via ···1179), never from the IRA. Spending is identical across strategies; the "taxable cash" column only tracks RMD cash in minus taxes and surcharges out.
Not modeled: extra gains realized when selling stock to pay the conversion tax; pension not inflation-adjusted in reality; the 5-year rule on Roth earnings (not an issue after 59½ for conversions themselves); heirs' 10-year rule; future tax-law changes.