IRMAA means Income-Related Monthly Adjustment Amount. It is a surcharge Social Security adds to your monthly Medicare Part B premium and, separately, to your Part D drug premium when your income from two years earlier is above a threshold. For 2026, it starts when income is above $109,000 for a single filer or above $218,000 for a married couple filing jointly, according to the Social Security Administration.
If Social Security sent you a letter about an "income-related monthly adjustment amount," this is the charge the letter means. The letter can be confusing because it is about Medicare premiums, but the decision comes from your tax return.
For 2026, the standard Medicare Part B premium is $202.90 a month, according to the Centers for Medicare & Medicaid Services (CMS). IRMAA is added on top of that. The combined Part B plus Part D surcharge runs from $95.70 a month to $578.00 a month per person, according to CMS 2026 premium tables.
This page explains who pays IRMAA, why an old tax return decides your current premium, how this year's brackets work, and when the surcharge can be appealed.
Revised: 9/8/26
Jason Baar
Fee-Only Medicare Advisor
NPN #2033715
See how the 2026 IRMAA brackets work, why Medicare looks back two years, and which planning moves can help you stay under the lines. No email address or form.
The long answer
Who pays IRMAA
IRMAA applies when your modified adjusted gross income is above the Medicare threshold. For Medicare, modified adjusted gross income means adjusted gross income from line 11 of Form 1040 plus tax-exempt interest from line 2a, so municipal bond interest counts. For 2026, the thresholds are income above $109,000 for a single filer and above $218,000 for a married couple filing jointly, according to the Social Security Administration. About 8 percent of people on Medicare pay IRMAA, according to CMS.
IRMAA applies per person. If both spouses are on Medicare and their joint income is over the line, both spouses pay it. If only one spouse is on Medicare, only that spouse pays it. There are two separate surcharges, one added to the Medicare Part B premium and one added to the Part D drug premium.
The Part D IRMAA surcharge is separate from your drug plan's own premium. Medicare bills it, not the drug plan, and it can apply even when your drug plan premium is $0. If you have no Medicare drug coverage, you pay only the Part B part. There is a separate page on this site about Part D IRMAA. There is a Part D IRMAA: Why Medicare Is Billing You.
Why IRMAA uses an old tax return
Social Security does not use this year's income to set this year's IRMAA. For 2026 premiums, Social Security uses the 2024 tax return because that is the most recent complete return the IRS can provide. For 2027 premiums, Social Security will use the 2025 return.
That delay is why the system often misfires after retirement. The old return may show peak working income, even though the person is now living on lower retirement income.
The 2026 IRMAA brackets
Use the table below to see which 2026 tier your 2024 income falls in and what surcharge applies.
| 2024 income, single | 2024 income, married filing jointly | Part B premium per month | Part D surcharge per month | Total surcharge per month | Surcharge per year |
|---|---|---|---|---|---|
| $109,000 or less | $218,000 or less | $202.90 | $0 | $0 | $0 |
| $109,001 to $137,000 | $218,001 to $274,000 | $284.10 | $14.50 | $95.70 | $1,148 |
| $137,001 to $171,000 | $274,001 to $342,000 | $405.80 | $37.50 | $240.40 | $2,885 |
| $171,001 to $205,000 | $342,001 to $410,000 | $527.50 | $60.40 | $385.00 | $4,620 |
| $205,001 to $499,999 | $410,001 to $749,999 | $649.20 | $83.30 | $529.60 | $6,355 |
| $500,000 or more | $750,000 or more | $689.90 | $91.00 | $578.00 | $6,936 |
The amounts shown are the combined Medicare Part B plus Part D surcharge per person enrolled. Single filers use the same surcharge amounts, with tiers starting above $109,000. Married filing separately has its own much steeper structure. Source: CMS 2026 premium tables, released November 14, 2025. CMS publishes the 2027 figures in the fall of 2026, and this table is updated the week they are released.
IRMAA tiers are cliffs
IRMAA tiers are cliffs, not slopes. One dollar over a line puts you in the next tier for the whole year. For example, $274,001 of 2024 joint income instead of $274,000 raises the 2026 surcharge from $95.70 to $240.40 a month, about $1,736 more for the year, per person.
When IRMAA can be appealed
There are three main situations.
- Social Security used wrong or outdated tax data. This can happen after an amended return or an IRS error. You can ask Social Security for a new determination, and that request runs on a 60-day clock from the date of the letter.
- The tax numbers are right, but your income dropped because of a life-changing event Social Security recognizes. In that case, you can ask Social Security to recalculate the surcharge from your current, lower income using Form SSA-44.
- The tax numbers are right, and there was no qualifying event. This can happen after a business sale or a large Roth conversion. In that situation, no relief is available, but the spike falls out of the calculation after one year.
Social Security recognizes eight life-changing events.
- Work stoppage, meaning retirement
- Work reduction
- Marriage
- Divorce or annulment
- Death of a spouse
- Loss of income-producing property
- Loss of pension income
- Employer settlement payment
Form SSA-44
Form SSA-44 is the Social Security form used when your income dropped because of a life-changing event. It is free from Social Security at ssa.gov/forms, at any Social Security office, or by phone at 1-800-772-1213. The current packet is eight pages, about half of it instructions.
The form moves through five steps: the event and its date, the income estimate for the affected year, next year's estimate if income drops further, evidence, and signature and filing. Build the income estimate from real components, because Social Security later compares it with the tax return you actually file. If Social Security agrees, the correction applies to the year in question, including months already overcharged.
When doing it yourself works
Doing it yourself can work when the situation fits one of Social Security's eight life-changing events cleanly. That usually means one form, proof of the event, and an income estimate you can defend.
When professional help is worth a call
Professional help is worth a call when it is not clear which event or which year fits, when you are married filing separately, when your income sits near a line where a Roth conversion or a capital gain would move you into another tier, or when a filing came back denied.
Jason Baar, Fee-Only Medicare Advisor works for a flat, client-paid fee. He accepts no commissions from insurance companies and sells no insurance plans. Florida license W149493. NPN #2033715. Call (850) 810-1000.
IRMAA questions, answered
Is IRMAA recalculated every year?
Yes. Social Security recalculates IRMAA every year using the newer tax return, so a one-time high-income year usually affects one year and then drops out.
Do both spouses pay IRMAA?
If both spouses are on Medicare and their joint income is over the line, both spouses pay IRMAA. If only one spouse is on Medicare, only that spouse pays it.
Is IRMAA based on AGI or MAGI?
IRMAA is based on modified adjusted gross income. For Medicare, that means adjusted gross income from line 11 of Form 1040 plus tax-exempt interest from line 2a.
Does IRMAA apply to Part D?
Yes. IRMAA can apply to Part D separately from Part B, and Medicare bills the Part D surcharge separately from the drug plan's own premium.
Is Form SSA-44 really free?
Yes. Form SSA-44 is free from Social Security at ssa.gov/forms, at any Social Security office, or by phone at 1-800-772-1213.
Printed from JasonKnowsMedicare.com — “IRMAA, Explained: What It Is and Who Pays It”. The free IRMAA Planning Guide is available at JasonKnowsMedicare.com/pages/free-medicare-guides · Questions: (850) 810-1000
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This page is educational information, not personal financial, tax, or legal advice. For decisions about your own situation, talk with a qualified professional.