IRMAA · Mesa County · Colorado's Western Slope

What Are the IRMAA Brackets for 2027? Start at $111,000

One 2027 line is public; the rest arrive in November. Here is the line that is published, the 2026 table it replaces, the federal actuaries' projection for the rest, and why the top bracket has not moved since 2019.

Medicare On Main Data Desk

Published October 3, 2026 · 8 min read · Reviewed by Brian Penner

Here is the honest state of the 2027 IRMAA brackets as of early October: one number is published, four are not, and one is frozen. That is not a gap in anyone's research; it is how the calendar works every year. Medicare prints the first threshold in the handbook that mails in September, and CMS announces the full table when it announces the Part B premium, usually in the second week of November. If you are planning a year-end Roth conversion or wondering whether a 2025 house sale is about to show up on your Social Security statement, you do not have to wait for November to know roughly where you stand. Below is what is published, what the federal actuaries project, and how the lines are built.

What is published for 2027

The 2027 edition of Medicare & You says, on the Part D costs page: "If your income is above a certain limit (in 2027 it's $111,000 if you file individually or $222,000 if you're married and file jointly), you'll pay an extra amount in addition to your plan premium (sometimes called 'Part D IRMAA'). You'll also have to pay this extra amount if you're in a Medicare Advantage Plan that includes drug coverage" (Medicare & You 2027, p. 86). Part B and Part D use the same income thresholds, so that sentence sets the first Part B line too.

Two cautions on reading the handbook. Page 23 of the same book still quotes the 2026 Part B premium ($202.90) and the 2026 thresholds ($109,000 / $218,000), because CMS had not set the 2027 premium when it went to print, so quote each figure with its year. And "the first line" is the only one the handbook gives; nothing in it tells you where the 35% tier ends and the 50% tier begins for 2027.

The 2026 table the 2027 one will replace

For orientation, here is the full 2026 table from CMS's November 14, 2025 fact sheet, based on 2024 returns. The "share of program cost" column is the percentage of the average Part B cost you pay at each tier; the standard premium covers 25%.

Source: CMS — 2026 Medicare Parts A & B Premiums and Deductibles / 2026 Part D IRMAA (Nov 14, 2025). Married filing separately (and lived with your spouse during the year): $0 up to $109,000; $446.30 from $109,001 to $390,999; $487.00 at $391,000 and above. Part D surcharges are paid to Medicare, not to the plan, and apply to Advantage plans with drug coverage too — see the Advantage-plan post.

What the 2027 table will look like: published, projected, frozen

The table below separates the three kinds of 2027 information so nothing projected gets mistaken for something official. The dollar surcharges in the right-hand columns are the intermediate estimates from Tables V.E3 and V.E4 of the 2026 Medicare Trustees Report, prepared by CMS's Office of the Actuary in spring 2026. They are the federal actuaries’ own projection; they are not the November announcement.

Sources: first line, Medicare & You 2027; top line, 42 U.S.C. § 1395r(i)(5)(C); surcharge estimates, 2026 Trustees Report, Tables V.E3 and V.E4, intermediate assumptions. The same report estimates the 2027 standard Part B premium at $209.50 — covered here.

Read the surcharge columns as a shape, not a quote. The actuaries' 2027 estimates run about 3% above 2026 at every tier, which is simply the projected growth in Part B costs; the final numbers will differ by some dollars once CMS sets the actual 2027 premium. The projection also counts about 6.6 million people paying a Part B surcharge in 2027, up from 6.1 million in 2026 — the thresholds rise with general inflation while retirement incomes, especially required minimum distributions, often rise faster.

How the missing lines get set

The thresholds are not chosen each fall; they are calculated. Federal law says each dollar amount is increased by the percentage by which "the average of the Consumer Price Index for all urban consumers (United States city average) for the 12-month period ending with August of the preceding calendar year" exceeds the same average for the base period, and the result is "rounded to the nearest multiple of $1,000" (42 U.S.C. § 1395r(i)(5)(A)–(B)). The regulation repeats the rule in plain words: "CMS will set all modified adjusted gross income threshold amounts for the following year by increasing the preceding year's threshold amounts by any percentage increase in the Consumer Price Index rounded to the nearest $1,000" (20 CFR § 418.1105(c)).

Three practical consequences:

• The August CPI data is in, so the 2027 lines are already determined — they are just not announced. The first line moving from $109,000 to $111,000 tells you the indexing step for this year was small; because every line is rounded to the nearest $1,000 separately, the higher lines may move by a different number of thousands than the first one did. Do not assume the second line is exactly $137,000 plus the same increase.
• Joint-return lines are exactly double the single lines for the first four thresholds (§ 1395r(i)(3)(C)(ii)), which is why the handbook can give $111,000 and $222,000 together. The exception is the top line, where the joint amount is 150%, not 200%: $750,000.
• The regulation says September; practice says November. § 418.1105(c) says CMS "will publish the amounts in the Federal Register in September of each year." In recent years the full IRMAA table has come out with the Part B premium announcement in mid-November instead. Plan on November, and treat anything you read before then (including the projections above) as an estimate.

Why the top bracket never moves

If you have watched the lower lines climb every year while the $500,000 line sat still, that is the law working as written. Section 1395r(i)(5)(C)(i) says the inflation adjustment "shall not apply with respect to each dollar amount in paragraph (3) of $500,000." Paragraph (ii) adds that "in the case of any calendar year beginning after 2027," the $500,000 amount is finally indexed, measured from the 12-month CPI-U average ending August 2026 (42 U.S.C. § 1395r(i)(5)(C)). So 2027 is the last year the 85% tier starts at exactly $500,000 single / $750,000 joint; from 2028 it drifts upward with inflation like the others.

The Trustees Report notes the same thing in its own words: the thresholds "were not indexed to inflation in the years 2011 through 2019 but are indexed thereafter," and the Bipartisan Budget Act of 2018 "established an additional premium level beginning in 2019" (2026 Trustees Report, Table V.E3 notes). For a Mesa County household that sold a business or a ranch in 2025 and landed above $750,000, the frozen line means there is no inflation relief this year, and the 85% tier applies in full for 2027.

What this means in Grand Junction

Sources: Medicare & You 2027 · CMS Medicare Monthly Enrollment · CMS 2026 fact sheet ("roughly 8% of people with Medicare Part B"). The county estimate is 8% of 41,709; Mesa County's income mix may differ from the national one in either direction.

The people who get surprised by IRMAA in Mesa County are rarely the ones with steady high incomes; they budgeted for it. The surprises come from one-year spikes on the 2025 return that show up in the 2027 premium: a PERA or federal retiree who also took a lump-sum payout, a couple who sold a long-held Redlands or Palisade home with a gain above the exclusion, a Roth conversion sized for the tax bracket but not for the IRMAA bracket, a first required minimum distribution at 73, or a capital gain from rebalancing. With a couple's first line at $222,000, a household with $160,000 of pension and Social Security income has about $62,000 of room before a 2025 event starts a 2027 surcharge; the same event in 2026 lands on the 2028 premium instead.

If the spike was a one-time event, the surcharge is also one-time: the 2028 premium will be based on your 2026 return, and the tier resets on its own. If the spike came with retirement — you stopped working or cut back — that is a life-changing event, and Social Security can use your lower current income instead of the 2025 return if you file Form SSA-44 with proof (SSA). The appeal post walks through the form; the short version is that retirement counts and a sale does not.

What I would do between now and November

1. Find your 2025 MAGI. Adjusted gross income plus tax-exempt interest from your 2025 return. If it is under $111,000 single or $222,000 joint, you are done; no 2027 surcharge.
2. If it is over, know your approximate tier now. Use the 2026 lines as a floor — the 2027 lines will be at or a little above them. If you are within a few thousand dollars of a 2026 line, wait for November before concluding which tier you are in.
3. Watch the mail in late November and December. Social Security's initial determination letter tells you the tier and the year of the return it used. Check the year; if SSA used an older return because the 2025 one was not yet on file, you can ask it to use the 2025 return.
4. Retired in 2025 or 2026? Start the SSA-44 paperwork now. A life-changing event with a lower current-year estimate is the one appeal that works.
5. Planning 2026 income with your tax advisor? Everything you do before December 31 lands on the 2028 premium, which the actuaries project at a standard $224.50. Qualified charitable distributions, the size and timing of conversions, and which account a withdrawal comes from are the usual levers. We stay on the Medicare side of that conversation.

How we know all this: the Medicare On Main Data Desk frames every article with public data — here, the 2027 Medicare & You handbook, CMS's November 14, 2025 fact sheet on 2026 premiums and IRMAA, Tables V.E3 and V.E4 of the 2026 Medicare Trustees Report, the IRMAA statute and regulations, and CMS's county enrollment data. Projections are labeled as projections; the Mesa County estimate is our arithmetic from a national share. IRMAA is set by Social Security from your tax return, not by any plan or agent, and nothing here is tax advice; confirm your figures with SSA, Medicare.gov or a licensed agent, and tax strategy with your tax advisor. We take no payment from any carrier to feature a plan.