Medicare IRMAA in 2026: The Income Cliff Inside the Part B and Part D Premium

An add-on to the premium, priced from two years ago

Medicare Part B has one published price and a second, hidden price list. The published price for 2026 is a standard monthly premium of $202.90, up $17.90 from $185.00 in 2025, with a $283 annual deductible.[1] The hidden list is the income-related monthly adjustment amount (IRMAA): an extra amount that is added to that premium when the modified adjusted gross income (MAGI) reported on your IRS tax return from two years earlier is above a threshold.[2]

Three properties matter for the price. First, it is a surcharge, not a tax and not a plan premium: it sits on top of the Part B premium and, for drug coverage, on top of the Part D plan premium.[2] Second, the income test lags: for the 2026 premium year the tested income is the MAGI of tax year 2024, or 2023 if 2024 was not available.[3] Third, it is priced centrally: the Social Security Administration states that the Centers for Medicare & Medicaid Services (CMS) calculates both the Part B premium amounts and the adjustment amount, and publishes them in the Federal Register each year.[3] CMS notes the surcharge reaches roughly 8% of people with Medicare Part B.[1]

The 2026 price list, step by step

CMS released the 2026 amounts on 14 November 2025. For a beneficiary filing an individual return, MAGI of $109,000 or less (or $218,000 or less for a joint return) pays the standard $202.90. Above that, the adjustment is charged in five steps: $81.20, $202.90, $324.60, $446.30 and $487.00 a month, producing total Part B premiums of $284.10, $405.80, $527.50, $649.20 and $689.90.[1] The Part D side is priced the same way and is charged in addition to whatever the drug plan itself costs: $14.50, $37.50, $60.40, $83.30 or $91.00 a month, calculated against a 2026 Part D national base premium of $38.99.[2]

One row in that table behaves differently. For a person who is married, lived with their spouse at some point in the year, and files a separate return, there is no middle ground: MAGI of $109,000 or less pays $202.90, anything above $109,000 and up to $391,000 pays an adjustment of $446.30 for a total of $649.20, and $391,000 or more pays $487.00 for a total of $689.90.[1] The CMS table marks the intermediate brackets for that filing status as not applicable; the surcharge does not climb in steps there, it jumps.

Why the steps are so steep

The step shape is not arbitrary. SSA's operating manual states that Part B beneficiaries usually pay about 25% of the true cost for Part B, and that the true cost an IRMAA beneficiary pays is 35% for level 1, 50% for level 2, 65% for level 3, 80% for level 4 and 85% for level 5.[3] The dollar figures are therefore the price of moving a household from paying a quarter of the program's cost to paying most of it.

The cost of a single dollar of income is easy to price. Crossing the first individual threshold by $1 costs $81.20 a month, or $974.40 a year (our arithmetic: 81.20 x 12). Sitting in the top step costs $689.90 a month, which is $8,278.80 for a year, against $2,434.80 for the standard premium - a difference of $5,844.00 a year (our arithmetic on the CMS amounts).[1] Because the test uses a two-year-old tax return, a single high-income year - a business sale, a large Roth conversion, a separation payment - can be charged twice: once in the year it is earned, and again in the premium year that follows.

The notice, the data and the lag

The first document most people see is a determination notice. SSA says it uses information from the Internal Revenue Service to make an initial determination based on MAGI data and tax filing status for a specific year, and that the notice informs the beneficiary of the determination and their appeal rights.[4] The same notice tells the beneficiary what to do if they have other information about their income, or if their circumstances have changed.[4]

SSA publishes the arithmetic of the total bill: the total Medicare Part B premium consists of the standard premium, plus late filing surcharges (applied to the standard premium, but not to the adjustment amount), plus the adjustment amount, minus any reduction for enrolling in a Medicare Advantage plan that offers a Part B premium reduction as a benefit.[3] Its own example is a $202.90 standard premium plus a $324.60 level 3 adjustment for a $527.50 total, and a second example in which a 10% late filing surcharge of $20.29 raises the bill to $547.79 before an estimated $70.00 Medicare Advantage reduction brings it to $477.79.[3] The manual also carries a warning worth pricing in: beneficiaries who pay the adjustment amount lose variable SMI premium protection.[3]

What can move the number

The determination is appealable on a clock. SSA's manual states that a beneficiary or the beneficiary's representative can file a request for reconsideration within 60 days of receipt of an IRMAA determination notice, and that date received means 5 days after the date on the notice unless the individual shows that they did not receive it within the 5-day period.[4] In practice that is 65 days from the date printed on the letter, unless receipt can be shown otherwise. Beyond the initial determination, the appeals process is set out at 20 CFR 418.1301 through 418.1355.[4]

Two levers change the bill without an appeal. A late enrollment or re-enrollment surcharge is calculated on the standard monthly premium rather than on the adjustment amount, so it stacks on the base, not on the surcharge.[3] And a Medicare Advantage plan that returns part of the Part B premium as a benefit reduces the total, as in SSA's $70.00 example above.[3] What does not change the amount is the plan you pick: the adjustment is set by CMS from tax data, not by the insurer.

Scope, dates and method

All figures on this page are 2026 premium-year amounts released by CMS on 14 November 2025 and restated in the Medicare costs fact sheet dated December 2025.[1][2] The scope is United States Medicare Part B and Part D enrollees with income above the published thresholds; the thresholds and dollar amounts are re-set every year, so a table copied from an earlier year is not a price for 2026.

This is a definition note, not enrollment, tax or investment advice, and not a quote from any insurer or agent. Where this page does arithmetic - annualised surcharges, the cost of one dollar of income - it is labelled as our arithmetic on the CMS amounts, and the underlying monthly figures are cited. Sources were read on 24 September 2026; the SSA manual sections cited carry their own effective dates (2 December 2025 and 5 June 2026).