Roth Conversion at 67: $1M IRA, Married

A Roth conversion moves money from a traditional IRA (where withdrawals are taxed as ordinary income) into a Roth IRA (where growth and withdrawals are tax-free). You pay tax on the converted amount today, at your current bracket, to avoid a larger bill later.

The case for converting rests on three converging forces. First, required minimum distributions begin at 73 — the IRS forces withdrawals whether you want them or not, adding to taxable income. Second, large RMDs can make up to 85 percent of Social Security taxable and trigger IRMAA Medicare premium surcharges. Third, after the first spouse’s death, the survivor files single and loses half the bracket width overnight.

Married filers have the widest conversion window: the 22 percent bracket ceiling is $201,050 in 2026 — roughly double the single ceiling. Each year before 73 is a chance to fill that space at today’s rate instead of paying 24 percent or more once RMDs compound the picture. Roth accounts carry no RMDs during your lifetime, so every converted dollar permanently exits the future RMD obligation.

IRMAA (Income-Related Monthly Adjustment Amount) surcharges apply when prior-year MAGI exceeds $212,000 (married). Large conversions can push past this threshold, generating Medicare premium increases two years later. Flagged years and surcharge amounts appear in the table above.

These pages assume 6 percent annual return, $24,000 Social Security income, bracket-filling to 22 percent each year before 73, and model to age 90. Your actual results depend on your income, SS benefit, and full tax picture.