IRMAA brackets for 2028
CMS has not published them. Anyone showing you an exact 2028 threshold today is estimating — and the arithmetic they need does not exist yet. Here is what is actually known, what is still missing, and when the real numbers arrive.
What is known today
| Item | Status | Detail |
|---|---|---|
| Income that counts | Still open | Your 2026 MAGI — the year you are in now, so still changeable |
| Part D national base premium | Not published | Due mid-2027 |
| Top-tier floors | Now indexed | Unlike 2027, the $500,000 and $750,000 top-tier floors DO become indexed for years beginning after 2027, so 2028 is the first year they can move. |
| MAGI thresholds | Not published | Expected October-November 2027 |
| Standard Part B premium | Not published | Same release |
| Part B and Part D IRMAA amounts | Not published | Same release |
CMS has published nothing at all for 2028 yet. Even the Part D national average bid, which lands mid-year, is not due until 2027.
Why nobody can give you the number yet
The MAGI thresholds are indexed under Social Security Act §1839(i)(5), 42 U.S.C. §1395r(i)(5) using the Consumer Price Index for all urban consumers (CPI-U), United States city average, measured over the 12-month period ending with August of the preceding calendar year, versus the 12-month period ending with August 2018 (for years beginning with 2020).
For 2027 that means the 12-month average ending August 2026. The Bureau of Labor Statistics publishes the August figure in mid-September. Until then the final input to the formula does not exist — so an exact 2027 threshold cannot be computed by us, by CMS, or by any of the sites currently publishing one.
That is why their numbers disagree. Surveying pages ranking for this query, the first single-filer threshold is variously given as $109,000, $111,000, $112,000 and $113,000, and the joint figure as $222,000, $224,000 and $226,000. Each is a different unstated inflation assumption. None shows its working.
When BLS publishes the August 2026 CPI-U, we will compute the projection properly — against the statutory 2018 base, with the inputs shown — and publish it here. When CMS releases the official figures in October-November 2027, this page becomes the official table, dated and sourced.
Illustrative range, clearly labelled
You probably came here for a number, so here is the honest version: what the 2026 thresholds would look like at a few rates of increase. For scale, the thresholds actually rose 2.83% from 2025 to 2026 ($106,000 → $109,000 single).
Two years of unknown inflation sit between the published 2026 figures and 2028, so these are wider bounds than a projection - they show what a sustained rate would produce, not what will happen. The top-tier floors are shown moving because they become indexed for 2028; for 2027 they do not.
| Tier | 2026 single (official) | at +0% | at +2% | at +3% | at +5% |
|---|---|---|---|---|---|
| Standard | $109,000 | $109,000 | $111,000 | $112,000 | $114,000 |
| Tier 1 | $137,000 | $137,000 | $140,000 | $141,000 | $144,000 |
| Tier 2 | $171,000 | $171,000 | $174,000 | $176,000 | $180,000 |
| Tier 3 | $205,000 | $205,000 | $209,000 | $211,000 | $215,000 |
| Tier 4 | $500,000 | $500,000 | $510,000 | $515,000 | $525,000 |
| Top tier | $500,000 | $500,000 | $510,000 | $515,000 | $525,000 |
Joint thresholds are double the single figures at every tier except the top. Unlike 2027, the $500,000 and $750,000 top-tier floors DO become indexed for years beginning after 2027, so 2028 is the first year they can move. The married-filing-separately floor moved DOWN from $394,000 (2025) to $391,000 (2026), so it does not track the same index as the other lines. We do not project it.
What you can actually act on
2028 is the year you can still change. Because IRMAA looks back two years, your 2028 surcharge will be set by the income you are earning right now, in 2026. That return has not been filed. Nothing about it is fixed yet.
Every other year on this site is already decided. This one is not — which makes it the only one where a decision you take this month changes what you pay. A Roth conversion, a property sale, an inherited IRA withdrawal or a large capital gain booked before 31 December lands in 2026 MAGI and shows up as a higher premium in 2028.
The thresholds are not published, so you cannot aim at an exact line. But the mechanism is fixed and the 2026 lines are the best available reference: if you are anywhere near one, the cost of crossing it is real money and the 2026 table shows exactly how much.
If your income has since dropped because of a life-changing event — retirement, a spouse’s death, divorce, loss of a pension — you may be able to have the surcharge reduced using Form SSA-44, rather than waiting two years for it to unwind on its own. How that works.