Part D IRMAA is a separate surcharge on Medicare drug coverage for people over the income line. Medicare bills it separately from the plan, even if the drug plan itself has a $0 premium.
This bill catches people off guard because the drug plan can look free. The plan may show a $0 premium, but Medicare can still add a separate Income-Related Monthly Adjustment Amount, called IRMAA, for Part D drug coverage.
For 2026, the Part D surcharge ranges from $0 to $91.00 a month per person, according to the Centers for Medicare & Medicaid Services (CMS) 2026 premium tables released November 14, 2025. The table on this page shows the surcharge by income.
Revised: 9/8/26
Jason Baar
Fee-Only Medicare Advisor
NPN #2033715
This free printable PDF explains the Medicare surcharge in plain language for people seeing it for the first time, with the Part B and Part D tables in one place. No email address or form.
The long answer
How Part D IRMAA works
Part D IRMAA uses the same income test as Part B IRMAA. Medicare looks at modified adjusted gross income, which means adjusted gross income plus tax-exempt interest, from the tax return two years back. That means 2026 uses 2024 income.
The same six tiers and the same income thresholds apply to both surcharges. For 2026, IRMAA starts above $109,000 for a single filer or $218,000 for a joint return, according to the Social Security Administration. The surcharge is per person, and Medicare decides it again each year from the newer tax return.
How Medicare bills it
The Part D surcharge is not paid to the drug plan. Medicare bills it separately. It can come out of the Social Security payment, or Medicare can bill the person directly if Social Security benefits have not started.
The surcharge applies to drug coverage inside a Medicare Advantage plan as well as to a stand-alone Part D plan. A person with no Medicare drug coverage does not pay the Part D surcharge. But if the surcharge applies and is not paid, Medicare can end the person's Part D coverage.
2026 Part D IRMAA amounts
The table below shows the 2026 Part D surcharge amounts by income tier. These are the same income thresholds used for Part B.
| 2024 income, single | 2024 income, married filing jointly | Part D surcharge per month, 2026 |
|---|---|---|
| $109,000 or less | $218,000 or less | $0 |
| $109,001 to $137,000 | $218,001 to $274,000 | $14.50 |
| $137,001 to $171,000 | $274,001 to $342,000 | $37.50 |
| $171,001 to $205,000 | $342,001 to $410,000 | $60.40 |
| $205,001 to $499,999 | $410,001 to $749,999 | $83.30 |
| $500,000 or more | $750,000 or more | $91.00 |
Amounts are monthly and per person. The 2026 Part D surcharge amounts are $0, $14.50, $37.50, $60.40, $83.30, and $91.00, according to CMS 2026 premium tables released November 14, 2025. The 2027 figures are expected in the fall of 2026.
Appealing Part D IRMAA after income drops
If a life event such as retirement lowered income, Form SSA-44 asks Social Security to use current income instead of the older tax return. One Form SSA-44 covers both the Part B and Part D surcharge. The form is free at ssa.gov/forms.
When a call helps
A call can help if the bill does not match what you expected, if income changed after retirement, or if you need to understand how the Part B and Part D surcharges fit together. Jason Baar, Fee-Only Medicare Advisor, is paid a flat fee by clients, with no commissions, and can be reached at (850) 810-1000.
Printed from JasonKnowsMedicare.com — “Part D IRMAA: Why Medicare Is Billing You”. The free guide What Medicare Actually Costs at Higher Incomes is available at JasonKnowsMedicare.com/pages/free-medicare-guides · Questions: (850) 810-1000
You can find all 10 free Medicare guides as PDFs on the Free Medicare Guides page.
This page is educational information, not personal financial, tax, or legal advice. For decisions about your own situation, talk with a qualified professional.