Medicare IRMAA: Why Your Income at 62 or 63 Matters Now

If you're 62 or 63, Medicare probably feels like something to think about later. But one part of it isn't later — it's happening right now, based on your tax return this year. Here's why.

Quick facts

• Medicare premiums are based on your tax return from two years earlier — your income at 63 can set your premium at 65

• IRMAA is a cliff, not a gradual increase — going $1 over a threshold moves you into the entire next bracket

• For 2026, the standard Part B premium is $202.90/month; IRMAA can push that as high as $689.90/month, plus a separate Part D surcharge up to $91.00/month

• A one-time income spike (Roth conversion, business sale, large capital gain) can trigger a higher premium two years later — even if your income drops back down after

What IRMAA actually is

Medicare Part B and Part D premiums are income-adjusted. If your income is above certain thresholds, you pay extra on top of the standard premium — this is IRMAA, the Income-Related Monthly Adjustment Amount.

IRMAA starts once your modified adjusted gross income (MAGI) exceeds a threshold (i.e., $109,000 for single filers or $218,000 for joint filers in 2026). Above that, premiums step up through five brackets — reaching as high as $689.90/month for Part B and an additional $91.00/month for Part D, per person, at the top bracket. See the current IRMAA brackets and surcharges for up-to-date figures, since these thresholds adjust most years. (Source: CMS, effective January 1, 2026.)

The part that catches people off guard: the two-year lookback

Medicare doesn't look at your income the year you enroll. It looks at your tax return from two years earlier. For 2026, Medicare is charging IRMAA based on 2024 tax returns.

So if you're 63 this year, the income on this year's tax return is what could determine your premium when you turn 65. There's no way to fix it after the fact except by appealing through a documented life-changing event (job loss, divorce, death of a spouse) using Form SSA-44 — normal income fluctuation doesn't qualify.

Why this matters for decisions you're making right now

If you're planning a Roth conversion, selling a business, taking a large capital gain, or doing anything else that spikes your taxable income in the next year or two, that decision could follow you into a higher Medicare premium bracket two years later — even in a year when your actual income is lower.

> This is general education, not tax advice. Talk to a CPA or financial advisor about the timing of any income-generating move before you make it. I can help you understand how a given income level affects your Medicare premium, but I can't advise you on the tax strategy itself.

When you actually get to enroll

Separately from IRMAA, it's worth knowing your enrollment timeline now so you're not scrambling at 65. Your Initial Enrollment Period (IEP) is a 7-month window:

• Starts 3 months before the month you turn 65

• Includes your birthday month

• Runs 3 months after your birthday month

Since 2023, if you enroll during the 3 months after your birthday month, coverage now starts the first of the month after you sign up — a change from the old rules, which could delay coverage by two to three months. (Source: Social Security Administration.)

What to actually do at 62 or 63

• If you're doing a Roth conversion or any major income event in the next couple of years, loop in a tax advisor on the timing — not just the tax bill, but the Medicare premium two years out

• Mark your Initial Enrollment Period on your calendar now — 3 months before your 65th birthday month

• If a life-changing event affects your income later (job loss, divorce, death of a spouse), know that Form SSA-44 exists to appeal an IRMAA determination — you don't have to wait two years for it to self-correct

For more on what else to think through before 65, see Considerations Before You Turn 65 and What Does Medicare Cost in 2026?.

Premium and IRMAA figures reflect 2026 amounts and adjust most years. See the current IRMAA brackets or verify at medicare.gov.