IRMAA: The Income-Related Medicare Premium Surcharge
IRMAA is the extra amount higher-income beneficiaries pay on top of the standard Medicare Part B and Part D premiums. In 2025 the standard Part B premium is $185 a month — but above an income threshold, surcharges stack on top. The detail almost nobody sees coming: it's based on your income from two years ago, and it's a cliff, not a slope.
- The rule: in 2025, a single filer with MAGI at or below $106,000 (married ≤ $212,000) pays the standard $185 Part B premium. Above that, IRMAA adds surcharges in tiers, rising to a top tier above $500,000 single / $750,000 married.
- The two-year lookback: 2025 IRMAA uses your 2023 MAGI. A one-time spike — a Roth conversion or a home sale in 2023 — can raise your Medicare premiums in 2025.
- It's a cliff: $1 over a threshold moves you into the next tier for the whole year. After a life-changing event like retirement, you can appeal with SSA Form SSA-44.
Where the AI summary above gets this wrong
"Higher earners pay more for Medicare."
True as far as it goes — but the three details that actually matter for planning are missing:
- It uses income from two years ago — 2025 IRMAA is set from your 2023 MAGI, so a one-time event like a Roth conversion or a home sale shows up as higher premiums two years later, not in the year it happened.
- It's a cliff, not a phase-in — the tiers are hard brackets. A single dollar over a threshold can cost you hundreds of dollars across Part B and Part D for the entire year.
- It's appealable — if a life-changing event such as retirement or divorce dropped your income, you can ask Social Security to use a more recent year by filing Form SSA-44.
When a near-retiree who wrote in turned 64, she did a large Roth conversion in a low-income year — smart on its own terms. What she didn't model was that the same conversion would push her MAGI over an IRMAA threshold, and that the bill would arrive on her Medicare premiums two years later. Here's the version that would have flagged it.
01 What IRMAA is and the two-year lookback
IRMAA stands for the Income-Related Monthly Adjustment Amount. It's an extra charge added to your Medicare Part B and Part D premiums when your income is above a set threshold. Most beneficiaries never pay it — they pay only the standard premium, which is $185 a month for Part B in 2025. Higher-income beneficiaries pay that standard amount plus a tiered surcharge.
The key mechanic is the two-year lookback. Social Security sets your IRMAA from your modified adjusted gross income (MAGI) from two years prior. So your 2025 IRMAA is based on the MAGI reported on your 2023 tax return — adjusted gross income plus any tax-exempt interest. That lag is why IRMAA catches people off guard: an income event today reshapes a Medicare bill that doesn't arrive for two years.
- Standard, no surcharge (2025, based on 2023 MAGI): single MAGI at or below $106,000, or married filing jointly at or below $212,000.
- Above the threshold: a surcharge is added to both the Part B and the Part D premium, in tiers that climb with income.
- Top tier: single MAGI above $500,000, or married above $750,000, pays the highest surcharge.
Source: SSA — Medicare Premiums: Rules for Higher-Income Beneficiaries
02 Worked example: your tier and premium
Enter your MAGI and filing status to see which IRMAA tier you land in and the resulting total monthly Part B premium. Tier thresholds are approximate 2025 figures, based on your 2023 MAGI.
Shows: your 2025 IRMAA tier and the total monthly Part B premium (standard $185 plus the tier surcharge), using approximate 2025 thresholds based on 2023 MAGI. Ignores: the Part D IRMAA amount, the appeal process, future inflation adjustments to the brackets, and the exact published dollar surcharges.
Run $90,000 single: you're under the $106,000 threshold, so there's no surcharge and you pay the standard $185. Now nudge MAGI to $107,000 — just over the line — and you jump into Tier 1, adding roughly $74 a month to Part B (plus a separate Part D surcharge). That's the cliff in action: $1,000 of extra income, none of it taxed at a punitive rate, still tips you into a full year of higher premiums.
On the defaults above, the worked example shows: You are in the Standard tier — no IRMAA surcharge. You pay the standard $185 Part B premium.
Source: Medicare.gov — Part B costs
03 The cliff — and how to appeal with SSA-44
IRMAA is structured as a series of hard brackets, not a smooth phase-in. Cross a threshold by a single dollar and you owe the full surcharge for that tier for the entire year — across both Part B and Part D. That's what makes income events near a bracket edge so expensive: there's no partial step, just the next full tier.
One dollar matters. Because the tiers are cliffs, a Roth conversion or capital gain that pushes MAGI even slightly over a threshold can cost hundreds of dollars in surcharges. When you're near a bracket, the last few thousand dollars of income are the ones to watch.
The relief valve is the appeal. If your income dropped because of a life-changing event — retirement, marriage, divorce, the death of a spouse, or loss of a pension or income-producing property — you can ask Social Security to use a more recent year instead of the two-year-old figure. You do this by filing Form SSA-44, attaching evidence of the event and your lower expected income. If approved, your IRMAA is recalculated on the newer, lower income.
Retiring is a qualifying event. The single most common reason IRMAA looks wrong is that the lookback year still reflects your full salary. If you've since retired, SSA-44 lets you base the premium on your actual retirement income rather than your old paycheck.
IRMAA is the reason I model the two-year lookback before any big income event in my 60s. A Roth conversion that nudges MAGI one dollar over a tier can cost more in Medicare surcharges, two years later, than the conversion itself saves in tax — and people almost never connect the two because of the lag. So whenever I'm sizing a conversion, a home sale, or a large capital gain near Medicare age, I check where it lands me against the IRMAA brackets first. The brackets are public; the surprise is entirely avoidable. And if life genuinely changed — you retired — don't just absorb a wrong bill. File SSA-44.
FAQ
What income does IRMAA use to set my 2025 Medicare premiums?
IRMAA for 2025 is based on your modified adjusted gross income (MAGI) from two years prior — your 2023 tax return. That two-year lookback means a one-time income spike in 2023, such as a Roth conversion or a home sale, can raise your Medicare premiums in 2025.
Is IRMAA a cliff or a gradual phase-in?
It is a cliff. The IRMAA tiers are hard brackets, so going one dollar over a threshold moves you into the next tier for the entire year. A single dollar of extra MAGI can add hundreds of dollars in surcharges across Part B and Part D.
Can I appeal IRMAA after I retire?
Yes. If a life-changing event such as retirement, marriage, divorce, or the death of a spouse reduced your income, you can ask Social Security to use a more recent year by filing Form SSA-44. If approved, your IRMAA is recalculated on the lower income.
Sources
Regulator references
- SSA — Medicare Premiums: Rules for Higher-Income Beneficiaries · Social Security Administration · 2025 · how IRMAA works, the two-year lookback, and the tier thresholdsThe income-related monthly adjustment amount and the two-year lookback that sets it.Last verified: 2026-06-21
- Medicare.gov — Part B costs · Centers for Medicare & Medicaid Services · 2025 · the $185 standard Part B premium and what IRMAA addsWhat Medicare costs: the Part B premium, deductibles, and the income-related surcharge.Last verified: 2026-06-21
- SSA — Form SSA-44 (Life-Changing Event) · Social Security Administration · 2025 · how to appeal IRMAA after a qualifying life-changing eventForm SSA-44, used to ask Social Security to reconsider IRMAA after a life-changing event.Last verified: 2026-06-21
- cms.govThe CMS newsroom, where the year's Medicare premium and deductible figures are announced.Last verified: 2026-09-07
Calculator unit tests · the assertions this page's worked example is checked against, and their last result
Changelog
- 2026-06-21 — initial publish (new format)
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Jordan Reeves
Founder of Talk Through Wealth. A software engineer for over a decade before turning to retirement planning, Jordan built the projection engine after watching family members get fragmented, country-by-country advice that never reconciled. He writes about retirement the way the engine computes it: month-by-month, lifetime-long, and skeptical of any rule of thumb that hasn't been run through the math.