What Is the Maximum Income to Avoid IRMAA?

The maximum income to stay off IRMAA entirely in 2026 is $109,000 of MAGI for a single filer and $218,000 for a married couple filing jointly, based on your 2024 tax return. That's the whole answer for whether you owe anything at all. The more useful question for most people, though, is how close to that line they can safely operate, because the penalty for guessing wrong isn't proportional to how far over you land.

Because IRMAA works as a cliff, one dollar of MAGI over $109,000 doesn't cost you a few cents of extra premium, it costs you the full jump to the first tier: $81.20 more per month for Part B and $14.50 more for Part D, or about $1,148 a year, for that one person. If both spouses are on Medicare and the household crosses the joint threshold, that cost applies to both of them independently, roughly $2,296 a year in total, triggered by a single dollar of MAGI.

The income sources that most often push someone over the line unexpectedly aren't the deliberate, plannable ones. A mutual fund's year-end capital gain distribution, an unanticipated bonus or RSU vest, tax-exempt municipal bond interest (which counts toward MAGI even though it's federally tax-free), or the taxable portion of a large one-time item like a home sale gain can all push MAGI over the threshold without a single Roth conversion or IRA withdrawal decision being involved.

There's a common misconception that a legitimate income drop can get an IRMAA determination reversed after the fact. It can, but only through SSA's life-changing-event appeal process (Form SSA-44), and only for specific qualifying events: marriage, divorce, death of a spouse, work stoppage or reduction, loss of income-producing property, loss of pension income, or an employer settlement payment. A one-time capital gain that inflated MAGI two years ago, with income back to normal since, does not qualify for that appeal. The number that mattered was locked in on the return for that specific year.

Staying under the line requires planning ahead by roughly two years, which is longer than most retirement income decisions get modeled for. If you or your spouse will be enrolling in Medicare in the next two to three years, or already are, any Roth conversion, capital gain harvest, or large IRA withdrawal in the current tax year should be checked against these thresholds before it happens, not discovered on next year's IRMAA determination letter.

Don't plan a Roth conversion or capital gains harvest to land exactly at $108,999 or $217,999. Build in a real buffer, several thousand dollars at minimum, to absorb a year-end capital gain distribution, an interest rate surprise, or a rounding difference between your projection and your actual 1099s.

If you're within two to three years of Medicare enrollment for yourself or a spouse, start modeling your MAGI against these thresholds now. The decision you make this tax year is really a decision about your Medicare premium two years from now, and by the time you see the IRMAA letter, the year that caused it is already closed.

• Planning income to land exactly at the threshold instead of leaving a buffer for year-end capital gain distributions or other surprises.
• Assuming a temporary income spike that gets reversed the next year will automatically be corrected; SSA's appeal process only covers specific life-changing events, not ordinary income fluctuation.
• Forgetting that tax-exempt municipal bond interest still counts toward the MAGI threshold even though it isn't taxed federally.
• Modeling this year's income against this year's Medicare premium instead of the premium two years out, which is what your current MAGI actually determines.