If your income crosses certain thresholds, Medicare adds a surcharge to your Part B and Part D premiums. Enter your income to see your tier, what you'd pay, and how much headroom you have before the next cliff.
IRMAA — the Income-Related Monthly Adjustment Amount — is a surcharge Medicare adds to your Part B and Part D premiums once your income passes certain thresholds. Higher earners pay more for the same coverage. The surcharge is set in tiers, and it applies per person, so a married couple on Medicare can each owe it.
Medicare doesn't use your current income — it uses your modified adjusted gross income from two years earlier, the most recent return available when premiums are set. This lookback is what makes IRMAA sneaky: a large Roth conversion or a big capital gain at 63 can raise your Medicare premiums at 65, long after you've forgotten the transaction. Planning conversions with this lag in mind is a core retirement-tax skill.
IRMAA tiers are hard edges. Earn one dollar over a threshold and you pay the full higher surcharge for the entire year — there's no gradual phase-in. That makes the headroom to the next tier genuinely valuable: keeping income just below a line can save hundreds or thousands. People manage this by timing conversions, spreading gains across years, or using qualified charitable distributions, often with a tax professional.