IRMAA Medicare Surcharge
A 5-tier Medicare surcharge applied to Part B and Part D premiums — based on your income from two years ago.
What it is
IRMAA (Income-Related Monthly Adjustment Amount) is a surcharge added to standard Medicare Part B and Part D premiums for higher-income beneficiaries. The standard Part B premium in 2026 is $202.90/month. IRMAA adds a fixed monthly surcharge on top of that amount — the higher your income, the higher the tier.
There are 5 IRMAA surcharge tiers above the standard premium. Each tier applies to your entire premium for the year — crossing a tier boundary by even $1 immediately places you in the higher tier, affecting a full 12 months of premiums.
IRMAA uses its own MAGI definition that differs from ACA MAGI. IRMAA MAGI adds back tax-exempt municipal bond interest. ACA MAGI does not. Using the wrong definition produces the wrong threshold.
How it triggers
CMS (Centers for Medicare & Medicaid Services) uses your MAGI from two years prior — not the current year. Your 2026 Medicare premiums are determined by your 2024 income. A Roth conversion you do today won't affect Medicare premiums until two years from now.
Tier 1 begins at $114,000 IRMAA MAGI for single filers and $228,000 for married filing jointly. Each tier adds a fixed monthly surcharge to both Part B and Part D premiums.
- IRMAA MAGI = AGI + tax-exempt muni bond interest (different from ACA, which does not add this back)
- CMS uses your MAGI from exactly two calendar years prior (the "lookback")
- Tier boundaries are adjusted annually by CMS — usually confirmed in November
- Both spouses pay the surcharge independently if MFJ and above threshold
- MFS filers face a compressed schedule that jumps directly to Tier 4
What it costs
Projected · low confidence — Premium Year 2028
Projected estimate only. Tier boundaries are encoded at the 0% inflation (conservative) scenario floor. CMS confirms 2028 brackets in November 2027. Actual thresholds may be higher if inflation continues. Part B premium amounts for 2028 are estimated — set by CMS annual rulemaking, not derived from CPI.
| Tier | MAGI range (Single) | MAGI range (MFJ) | Part B/mo | Part D/mo | Annual total |
|---|---|---|---|---|---|
| 0 | $0 – $114,000 | $0 – $228,000 | $0.00 | $0.00 | $0/yr ($0.00/mo) |
| 1 | $114,001 – $144,000 | $228,001 – $288,000 | $81.20 | $14.50 | $1,148/yr ($95.70/mo) |
| 2 | $144,001 – $179,000 | $288,001 – $358,000 | $202.90 | $37.50 | $2,885/yr ($240.40/mo) |
| 3 | $179,001 – $215,000 | $358,001 – $430,000 | $324.60 | $60.40 | $4,620/yr ($385.00/mo) |
| 4 | $215,001 – $507,999 | $430,001 – $761,999 | $446.30 | $83.30 | $6,355/yr ($529.60/mo) |
| 5 | $508,000+ | $762,000+ | $487.00 | $91.00 | $6,936/yr ($578.00/mo) |
Verified 2026-06-17 · The Finance Buff — IRMAA threshold CPI-U projections (0% conservative floor used)
At the top IRMAA tier, a single beneficiary pays approximately $5,844 more per year in Part B surcharges alone, before Part D. A couple pays more than double that. Even the first surcharge tier adds several hundred dollars per year.
A one-time Roth conversion that crosses an IRMAA tier boundary locks in the higher premium for a full calendar year. The present value of crossing even the first tier can exceed $3,000 per person over a decade.
If your income drops — due to retirement, a qualifying life-changing event, or an unusually high prior year — you can appeal IRMAA using SSA Form SSA-44, which allows CMS to use more recent income.
How to see your own IRMAA Medicare Surcharge headroom
CliffEdge computes your IRMAA MAGI, identifies which tier you are in, shows your headroom to the next tier, and calculates the present value of crossing a tier boundary. It uses a three-year lookback grid so you can see how past income affects current premiums.
Enter your income details — Roth conversion amounts, Social Security, IRA withdrawals, and municipal bond interest — to see your IRMAA position in real time.
Frequently asked questions
Does IRMAA apply to Medicare Advantage plans?+
Yes. IRMAA applies to Part B and Part D premiums regardless of whether you have Original Medicare or a Medicare Advantage (Part C) plan. Your MA plan premium is separate; IRMAA is added on top of the standard Part B premium.
Can I appeal IRMAA if my income dropped?+
Yes. If you had a qualifying life-changing event (retirement, divorce, death of spouse, reduction in work hours), you can file SSA Form SSA-44 requesting that CMS use a more recent tax year rather than the lookback year.
Is IRMAA the same for both Medicare Part B and Part D?+
IRMAA applies to both, but the surcharge amounts differ. Part B surcharges are larger. Part D surcharges are added on top of whatever your Part D plan premium is. Both are determined by the same MAGI lookback and tier thresholds.
Sources & data currency
The Finance Buff — IRMAA threshold CPI-U projections (0% conservative floor used)
https://thefinancebuff.com/medicare-irmaa-income-brackets.htmlVerified 2026-06-17
42 U.S.C. §1395r (Social Security Act §1839(i)) — IRMAA statutory authority
https://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-title42-section1395r&num=0&edition=prelimVerified 2026-06-17
All thresholds sourced from IRS, CMS, and HHS publications. Not financial advice — verify critical numbers before acting. See full methodology →