IRMAA Two-Year Lookback Projector (2026)
Enter your projected MAGI year-by-year. See which IRMAA tier sets your Medicare Part B + Part D surcharge two years out — and which conversion years are free of a surcharge.
2026 CMS brackets · last reviewed 2026-05-23
Your filing status & Medicare timeline
Projected MAGI by year
IRMAA MAGI (AGI + tax-exempt interest only — a narrower MAGI than the ACA's). Enter your adjusted gross income plus any tax-exempt interest, and nothing else. Roth conversion amounts are already inside AGI and count fully. Do not add non-taxable Social Security or the foreign earned income exclusion here — those are ACA-MAGI add-backs (IRC §36B(d)(2)(B)) and are not part of the IRMAA definition at 42 U.S.C. §1395r(i)(4). Adding them would overstate your MAGI and can show a surcharge tier you do not owe.
Surcharge projection
| Medicare year | Lookback year | Lookback MAGI | Tier | Monthly surcharge | Annual |
|---|
Next decision: Model conversions that stay under the tiers — find your Roth conversion sweet spot →
2026 IRMAA brackets (CMS)
The thresholds below are MAGI from the tax return two years prior. Surcharges are monthly, on top of the standard 2026 Part B premium of $202.90. Each bracket is a cliff — one dollar over a threshold pushes the entire year's surcharge to the next tier.
| Tier | MAGI (single) | MAGI (MFJ) | Part B surcharge | Part D surcharge | Total/mo |
|---|---|---|---|---|---|
| 0 (base) | $0 – $109,000 | $0 – $218,000 | $0.00 | $0.00 | $0.00 |
| 1 | $109,001 – $137,000 | $218,001 – $274,000 | $81.20 | $14.50 | $95.70 |
| 2 | $137,001 – $171,000 | $274,001 – $342,000 | $202.90 | $37.50 | $240.40 |
| 3 | $171,001 – $205,000 | $342,001 – $410,000 | $324.60 | $60.40 | $385.00 |
| 4 | $205,001 – $499,999 | $410,001 – $749,999 | $446.30 | $83.30 | $529.60 |
| 5 (top) | $500,000 and above | $750,000 and above | $487.00 | $91.00 | $578.00 |
Surcharges shown per Medicare-enrolled person. Couples with both spouses on Medicare pay 2× these amounts.
How the 2-year lookback works
Each fall, Social Security pulls your Modified AGI from the IRS for the tax return TWO years prior to the upcoming premium year. For 2028 Part B and Part D premiums, that's your 2026 return (filed in April 2027). The lookback is a hard cliff, not a marginal ramp — one dollar over an IRMAA threshold pushes the entire year's surcharge up to the next tier.
If you've had a life-changing event (retirement, work stoppage, loss of pension, divorce, death of spouse), file Form SSA-44 with Social Security to use a more recent year for the calculation.
Related calculators & guides
- RMD & IRMAA combined calculator — see how RMDs at 73+ stack into IRMAA tiers
- Roth conversion optimizer — find the conversion size that minimizes lifetime IRMAA + federal tax
- IRMAA brackets explained (2026)
- SSA-44 appeal: the lookback trap
- Full RMD & IRMAA Guide
Primary sources cited
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