The Medicare Surcharge Nobody Calls a Tax — But Your Bank Account Can't Tell the Difference

It is not called a tax. It doesn't come from the IRS. It shows up as a higher Medicare premium — and it hits because of something you did two years ago.

Meet IRMAA: the income-related monthly adjustment amount. Cross certain income thresholds and your Medicare premiums increase. Congress didn't call it a tax. Your bank account can't tell the difference.

What is an IRMAA surcharge?

Medicare premiums are not flat for everyone. Above certain income levels, you pay an income-related surcharge on top of the standard premium. It works in tiers, not on a gentle slope — which is the part that stings. One dollar over a threshold can move you into the next tier for a full year.

It also runs on a delay. Medicare generally looks at a prior-year income measure to set your current premium. So the bill arrives long after the decision that caused it, when nobody remembers making a decision at all.

What triggers a Medicare surcharge?

• A large retirement account withdrawal
• A Roth conversion done without watching the thresholds
• A one-time event: selling a rental, a business, a big appreciated position
• Required Minimum Distributions arriving bigger than expected (why they do)
• Simply having more ongoing income than the plan assumed

Notice that most of these are things a reasonable person does on purpose. Selling the shore house isn't a mistake. Selling it in the same year you convert an IRA and start a pension might be.

Why does IRMAA feel so unfair?

Because it is invisible until it isn't. Nobody connects "I sold the rental property in 2024" with "my Medicare premium went up in 2026." There's no line item explaining the cause. It just quietly reduces your net retirement income, month after month, for a year.

And it's a cliff, not a ramp. Being slightly over costs the same as being well over. Which means the fix is often measured in a few thousand dollars of timing.

How do you plan around it?

• Smooth your income. Avoid unnecessary spikes. Two moderate years usually beat one enormous one.
• Coordinate big events. If you know a sale is coming, build the year around it — including which accounts you don't touch.
• Check thresholds before you convert. A Roth conversion sized to a bracket but blind to IRMAA can be a win on one line and a loss on another (and conversions have other costs too).
• Know the two-year lag. Plan the year, not the month.

Questions to ask

• "Could my current income plan trigger a Medicare surcharge?"
• "Which upcoming years should we deliberately keep income lower?"
• "How do we time a major sale around Medicare costs?"

Bottom line: even genuinely smart strategies can trigger higher premiums when they're executed without coordination. That's trap three of four.

Educational only — not tax or legal advice. Tax rules change and outcomes depend on your situation. Talk to a qualified tax professional and an advisor before you move money.