IRMAA — the Income-Related Monthly Adjustment Amount — is the surcharge that higher-income retirees pay on top of their standard Medicare Part B and Part D premiums. For 2026, the standard Part B premium is $202.90 per month, and the tables below show exactly how much extra each income tier owes. Social Security determines your tier from the MAGI on your 2024 tax return — the two-year lookback that catches many people by surprise.
Single & Married Filing Jointly
| MAGI — Single | MAGI — Married Joint | Part B / mo | Part B IRMAA | Part D IRMAA |
|---|---|---|---|---|
| ≤ $109,000 | ≤ $218,000 | $202.90 | $0.00 | $0.00 |
| $109,001–137,000 | $218,001–274,000 | $284.10 | $81.20 | $14.50 |
| $137,001–171,000 | $274,001–342,000 | $405.80 | $202.90 | $37.50 |
| $171,001–205,000 | $342,001–410,000 | $527.50 | $324.60 | $60.40 |
| $205,001–499,999 | $410,001–749,999 | $649.20 | $446.30 | $83.30 |
| ≥ $500,000 | ≥ $750,000 | $689.90 | $487.00 | $91.00 |
"Part B / mo" is the total monthly Part B premium — the standard $202.90 plus the Part B IRMAA in the next column. The Part D IRMAA is billed on top of whatever your drug plan already charges.
Married Filing Separately
Couples who file separately but lived together during the year face a much narrower set of brackets — the surcharge jumps to a high tier almost immediately, with no gradual middle steps.
| MAGI — Married, filing separately | Part B / mo | Part B IRMAA | Part D IRMAA |
|---|---|---|---|
| ≤ $109,000 | $202.90 | $0.00 | $0.00 |
| $109,001–393,999 | $649.20 | $446.30 | $83.30 |
| ≥ $394,000 | $689.90 | $487.00 | $91.00 |
How to read this table
Find the row your 2024 MAGI falls into for your filing status. Remember the brackets are cliffs, not gradual phase-ins — one dollar over a threshold moves you to the next row and applies the full surcharge for the entire year, on both Part B and Part D. Use the IRMAA calculator to see how close you are to the next cliff, or read how to appeal with Form SSA-44 if your income has since dropped.
What counts as MAGI for IRMAA
The income figure that sets your bracket is your Modified Adjusted Gross Income. For IRMAA, that is your Adjusted Gross Income (Form 1040, line 11) plus tax-exempt interest (line 2a) — for example, interest from municipal bonds. That add-back surprises many retirees, because income they think of as "tax-free" still counts toward the surcharge. Common items that raise MAGI include traditional IRA and 401(k) withdrawals, Roth conversions, capital gains from selling a home or investments, pension and annuity income, and the taxable portion of Social Security benefits.
Worked example: a single filer
Suppose a single filer had a 2024 MAGI of $150,000. That lands in the third row ($137,001–171,000). Their total Part B premium is $405.80/month — the $202.90 base plus a $202.90 Part B IRMAA — and they also owe a $37.50 Part D IRMAA. The IRMAA portion alone adds up to ($202.90 + $37.50) × 12 = $2,884.80 for the year, on top of the standard premiums they would have paid anyway.
Worked example: a married couple
Now take a couple filing jointly with a 2024 MAGI of $300,000, both enrolled in Medicare. That falls in the $274,001–342,000 joint row: a $202.90 Part B IRMAA and $37.50 Part D IRMAA — per person. Because IRMAA is charged individually, the household pays ($202.90 + $37.50) × 2 people × 12 months = $5,769.60 in surcharges for the year. Had their MAGI been $218,000 or less, they would have owed none of it — a vivid illustration of why the cliff matters.
How IRMAA is billed
Your Part B premium (standard amount plus any Part B IRMAA) is usually deducted directly from your monthly Social Security check. The Part D IRMAA works differently: even though your drug plan premium goes to a private insurer, Medicare bills the Part D surcharge separately, either by deducting it from Social Security or by sending you a bill. If you are not yet collecting Social Security, Medicare bills you directly for both.
Frequently asked questions
What income year is used for 2026 IRMAA?
Your 2024 federal tax return. Social Security uses a two-year lookback because it is the most recent return the IRS can share, so 2026 premiums are set by 2024 MAGI.
Do both spouses pay IRMAA?
Yes. IRMAA is charged per person enrolled in Medicare. If both spouses are enrolled and household MAGI is over the joint threshold, each pays the surcharge, roughly doubling the annual cost.
Does tax-exempt interest count?
Yes. Tax-exempt interest (such as from municipal bonds) is added back to your AGI when calculating MAGI for IRMAA, so it can push you over a threshold even though it isn't taxed.
Can these brackets change?
The first four brackets adjust for inflation each year; the top bracket is currently fixed. The 2026 figures shown here are the official amounts CMS published in November 2025. See the projected 2027 brackets for planning ahead.
Figures are the official 2026 amounts published by CMS. This page is general educational information, not financial, tax, or legal advice. Verify your own premium with Medicare.gov or SSA.gov.