IRMAA is a cliff, not a slope
Crossing a tier threshold by even one dollar applies the higher surcharge to your entire premium, not just the amount over the line — which makes a large Roth conversion or a big capital gain in the lookback year worth planning around. Weighing a conversion or a Required Minimum Distribution against this? See the RMD Calculator or Roth vs Traditional Calculator.
Frequently asked questions
Why does this use my income from two years ago?
The Social Security Administration sets your IRMAA tier from your tax return filed two years prior — this year's premium is based on that older MAGI, not your current income, because that's the most recent return actually on file.
What if my income dropped since then?
A life-changing event — retirement, divorce, the death of a spouse, and several others — lets you request a new IRMAA determination using more recent income via Form SSA-44, instead of waiting for the two-year lookback to catch up.
Are these brackets and premiums the current ones?
The tier thresholds and Part B/D surcharges shown here are illustrative, recent-year figures — Medicare adjusts both every year. Confirm the exact numbers for your year at medicare.gov before budgeting around this.
Last updated: June 2026