Why your Medicare premium is higher than your neighbor's

Two people on the same Medicare Supplement plan, seeing the same doctors, with the same everything — and one of them is paying a noticeably higher Part B premium. It comes up more often than you'd think.

The usual explanation is IRMAA, which stands for Income-Related Monthly Adjustment Amount. It's a surcharge added to Part B and Part D premiums for higher earners.

Where it starts

For 2026, IRMAA kicks in once your modified adjusted gross income crosses $109,000 if you file as an individual, or $218,000 if you file jointly.

The thing to understand about it is that it's a cliff rather than a slope. One dollar over a threshold moves you into the next bracket for the whole year — there's no partial step and no averaging across the line. From there the surcharge climbs in bands as income climbs, and Social Security publishes those bands, so it's worth looking yours up rather than estimating it.

The part that catches people out

The income year Medicare uses isn't this one. It's your tax return from two years earlier, so your 2026 premium is based on what you reported for 2024.

That lag is why the bill so often feels wrong. A retirement, a divorce, the death of a spouse, selling a business, the year you finally stopped working — any one of those can leave your current income looking nothing like the return being used against you.

The form most people never hear about

If one of those life-changing events applies to you, you can ask Social Security to recalculate using your current income instead. The form is SSA-44, and the events it covers are quite specific: marriage, divorce or annulment, death of a spouse, work stoppage, work reduction, loss of income-producing property, loss of pension income, and employer settlement payments.

Filing it is how you avoid paying a surcharge for a full year on money you no longer earn. Plenty of people just pay it instead, because nothing in the letter they got suggested there was a form at all.

What to do if your bill looks wrong

The first question isn't whether Medicare made a mistake, because it usually hasn't. The question is whether your current income matches the return being used.

If it doesn't, and one of those events is the reason, then what you have is a fixable gap rather than a permanent cost. Send us the letter and we'll tell you whether SSA-44 applies to you. No charge — and if the number is correct after all, we'll tell you that too.