Medicare Premium Estimator

Why are two retired couples with nearly identical net worth paying wildly different Medicare premiums? Because Medicare doesn’t price on wealth. It prices on the income you reported two years ago, and one dollar over a threshold raises the bill for an entire year. This tool tells you which tier you’re in and how close you are to the next cliff.

The decision it solves

Most people assume the Medicare premium is the Medicare premium. It isn’t. Parts B and D carry an income surcharge called IRMAA, the income-related monthly adjustment amount, and it’s built as a staircase, not a ramp. Cross a threshold by a single dollar and you pay the full higher tier for all twelve months.

The decision this drives is income timing. A Roth conversion, a big capital gain, a property sale, or a fat RMD in one year quietly resets your Medicare premium two years out. Knowing the brackets before you act is the difference between a planned cost and a nasty surprise.

How the math works

The estimator takes your modified adjusted gross income and finds your tier. The key wrinkle is the two-year lookback: your 2026 premium is set by the income on your 2024 tax return. So the number that matters today is the one you’re building this year for two years from now.

For 2026 the standard Part B premium is $202.90 a month, and a married couple stays there as long as their MAGI is at or below $218,000 (or $109,000 single). Above that, the surcharges climb in steps:

• MAGI to $274,000 (couple): +$81.20/mo Part B, +$14.50/mo Part D per person
• MAGI to $342,000: +$202.90/mo Part B, +$37.50/mo Part D
• MAGI to $410,000: +$324.60/mo Part B, +$60.40/mo Part D
• MAGI to $750,000: +$446.30/mo Part B, +$83.30/mo Part D
• MAGI at $750,000 and above: +$487.00/mo Part B, +$91.00/mo Part D

The tool flags how many dollars of headroom sit between your income and the next step up.

A worked example

A married couple’s 2024 MAGI came in at $272,000. That sits inside the first surcharge tier, so in 2026 each spouse pays $202.90 plus $81.20 on Part B, about $284 a month each, plus the Part D surcharge.

Now suppose a Roth conversion had pushed their 2024 MAGI to $276,000 instead. That extra $4,000 vaults them into the next tier. Part B jumps to $405.80 a month each, more than $120 a month higher per person than the tier they just left. Across two people for a full year, that $4,000 of income bought them roughly $2,900 in added Part B premiums alone, more once the higher Part D surcharge is counted. The surcharge didn’t phase in. It snapped to the next rung the moment they crossed the line.

The part most people miss

IRMAA is a one-year event tied to one year’s income, which cuts both ways. A single high-income year, a home sale or a large conversion, raises your premium for just one year and then it resets. And a life-changing event like retirement itself can be appealed, because Medicare will sometimes use a more recent, lower income instead of the two-year-old figure. The tool helps you see the spike coming so you can decide whether to smooth the income, appeal it, or simply accept it as the toll on a smart move.

If your income is high

For affluent retirees the IRMAA staircase is a planning constraint, not a wall. Sometimes punching into a higher tier is worth it, when a Roth conversion that triggers one year of surcharge saves a decade of higher-taxed RMDs. The job is to cross the line on purpose, with the price tag in front of you, never by accident. See Medicare IRMAA brackets explained for the full tier-by-tier breakdown.

Check the bracket before you trigger the income, not after the premium notice arrives. Two years is plenty of time to plan, and zero time to undo.