The Income-Related Monthly Adjustment Amount (known as IRMAA) is a surcharge Medicare adds to your Part B and Part D premiums once your income passes a set threshold, $109,000 for a single filer or $218,000 for a couple in 2026. It is set by the income you reported two years earlier, so your 2026 premium follows from your 2024 tax return.
The surcharge matters for planning because the income that triggers it is partly yours to control. A Roth conversion, a large capital gain, or a required minimum distribution can push you over a line and raise your premiums for a full year. This guide lays out the 2026 brackets, explains why crossing a threshold works like a cliff, and covers the levers that hold your income under the next tier.
IRMAA keys off one number, your modified adjusted gross income, or MAGI. For Medicare's purposes, MAGI is your adjusted gross income plus any tax-exempt interest, mostly municipal bond interest. Nearly everything that lands in AGI counts toward it, including wages, pensions, taxable Social Security, interest, dividends, capital gains, and withdrawals from traditional IRAs and 401(k)s.
The IRMAA number. MAGI equals your adjusted gross income plus tax-exempt interest, taken from your tax return two years before the premium year. Your 2026 surcharge is set by your 2024 MAGI.
Social Security uses the most recent return the IRS has passed along, which runs about two years behind. The lag is why a change in income shows up in your premium so late, and why a one-time spike in a single year can raise your premiums even after your income has dropped back down.
The surcharge climbs through five tiers above the standard premium, and the 2026 figures below are set by 2024 MAGI. The standard Part B premium is $202.90 a month; the Part D column is the surcharge added on top of whatever your drug plan already charges.
| Single MAGI (2024) | Married filing jointly (2024) | Part B premium | Part D surcharge |
|---|---|---|---|
| $109,000 or less | $218,000 or less | $202.90 | $0 |
| $109,001 to $137,000 | $218,001 to $274,000 | $284.10 | +$14.50 |
| $137,001 to $171,000 | $274,001 to $342,000 | $405.80 | +$37.50 |
| $171,001 to $205,000 | $342,001 to $410,000 | $527.50 | +$60.40 |
| $205,001 to $500,000 | $410,001 to $750,000 | $649.20 | +$83.30 |
| Above $500,000 | Above $750,000 | $689.90 | +$91.00 |
At the top tier a single retiree pays $689.90 a month for Part B against the standard $202.90, plus roughly $91 more for Part D. Over a year the gap runs close to $6,900 for one person, and about double for a couple who both cross the line. Retirees who file married-separately face a steeper schedule, with the surcharge starting at $109,000 and reaching the top tiers far sooner, so filing status itself is worth checking before a high-income year.
IRMAA is a cliff, not a phase-in. Cross a threshold by a single dollar and you owe the whole surcharge for that tier, not a prorated slice of it. A single filer with MAGI of $109,000 pays the standard $202.90; at $109,001 the Part B premium jumps to $284.10, an extra $81.20 a month, or about $975 across the year, before the Part D add-on. One dollar of income can cost more than a thousand.
The cliff turns the last few thousand dollars of income before a threshold into the most expensive money in your plan. A Roth conversion sized to land $500 under the line and one sized to land $500 over it differ by a rounding error in taxable income but by a four-figure premium bill. Knowing where the next line sits is what makes the difference plannable.
Some income raises your MAGI and some does not, and the split is what makes the surcharge manageable, because it lets you pick which accounts to draw from in a year when you are close to a line. Several common sources of retirement cash flow feed MAGI.
Other money you live on stays out of the calculation.
A retiree living partly on Roth withdrawals and taxable-account principal can report far less MAGI than one pulling the same spending from a traditional IRA. Holding both Roth and traditional money is what gives you that choice, because it lets you decide how much taxable income to show in any given year.
A few moves keep MAGI under the next tier, and most of them work best in the years before required distributions begin.
The window between leaving work and starting Social Security or RMDs is often your lowest-income stretch, and it is the natural time to convert traditional money to Roth. Size the conversion to fill the space up to the next IRMAA line rather than blow past it, and you shift money out of accounts that will later force taxable RMDs. Our guide to Roth versus traditional accounts works through the tax math; the point for IRMAA is that Roth dollars never show up in MAGI again.
A qualified charitable distribution lets someone 70½ or older send money straight from an IRA to a charity, up to an inflation-indexed cap of just over $100,000 a year. The amount can satisfy your required distribution but never enters AGI, so it lowers the income IRMAA measures. For retirees who give to charity anyway, a QCD is one of the few ways to cut MAGI dollar for dollar.
Large one-time events are the usual IRMAA triggers, so spreading them out helps. Realizing a big capital gain, selling a property, or taking an extra-large withdrawal in one year can spike that year's MAGI and your premium two years on. Splitting a sale across two tax years, or pairing gains with offsetting losses, can keep any single year under a threshold. Required minimum distributions are harder to steer because the IRS sets the floor, but our guide to required minimum distributions covers the moves that shrink them before age 73, from earlier Roth conversions to QCDs.
The two-year lookback creates a common trap. You retire, your income falls, but your premium is still set by the higher salary you earned two years earlier. Social Security lets you appeal in that situation through a life-changing event.
Form SSA-44 covers a specific list of events that reduce income, including work stoppage or reduction (retirement counts), marriage, divorce, the death of a spouse, and loss of pension income. If one applies, you file the form with a recent tax return or a pay stub showing the lower income, and Social Security recalculates the surcharge from your current figures rather than the two-year-old return. Retirement itself is the most common ground, so a retiree hit with IRMAA in the first year or two off the job should check whether an appeal fits.
Losing a spouse can raise the survivor's Medicare premium even as household income falls. When one spouse dies, the survivor files as single the following year, and the single brackets start at half the married thresholds. A widow or widower with the same investment and pension income the couple had can land in a higher IRMAA tier on a smaller total income. The death of a spouse is a qualifying event on Form SSA-44, which can offset part of the jump, but the bracket shift is worth planning for while both spouses are alive, one more reason to build Roth balances that keep future MAGI down.
IRMAA is a surcharge you can plan around once you know where the lines sit. Track your MAGI against the 2026 brackets, remember the two-year lag, and treat the room under the next threshold as a budget for Roth conversions and capital gains rather than a line to cross by accident. If your income has fallen since the return that set your premium, file Form SSA-44 and ask for a recalculation. For the wider picture of what coverage costs once you are on Medicare, our guide to health care costs in retirement sets IRMAA alongside premiums, deductibles, and the gaps Medicare leaves.
The cleanest way to see how a conversion or a large withdrawal moves your income is to model it. Build your plan in the calculator, which draws down your accounts in a tax-aware order, and watch how shifting money between traditional and Roth changes the taxable income IRMAA measures. The rest of our health care guides cover Medicare and the pre-65 gap in more depth.
Model a Roth conversion or a large withdrawal in the calculator and watch how it moves the taxable income that sets your Medicare premiums.
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