2027 IRMAA Brackets: Projected Medicare Part B & D Chart

Not official yet — CMS typically confirms them around November 2026. The MAGI thresholds are computed from the final CPI-U under the statutory formula (Social Security Act §1839(i)(5)): six tiers from Standard (MAGI up to $112,000 single / $224,000 joint) up through Tier 5 ($500,000 single / $750,000 joint and above). The entry threshold is firm; Tiers 2-4 may land $1,000 higher ($142,000 / $177,000 / $212,000 single) depending on how CMS handles the October 2025 CPI-U that BLS never published.

Your 2025 MAGI. IRMAA always runs on a two-year lookback: your 2027 Medicare premium is set by the MAGI on your 2025 tax return (the one filed in early 2026), not your 2026 or 2027 income. That means the number that actually determines your 2027 premium is already fixed — it was locked in when you filed your 2025 return.

No — none of it is a CMS determination yet, and the figures come from two different processes. Part B premium and surcharges: CMS's own actuarial projection under the intermediate set of assumptions, Tables V.E2 and V.E3 of the 2026 Medicare Trustees Report — official figures, but a forecast, not the binding fact-sheet determination. Part D surcharges: derived from that report's projected Part D base beneficiary premium using the statutory formula in section 1860D-13(a)(7) of the Social Security Act. MAGI thresholds: computed, not estimated — the statutory base amounts indexed by the final CPI-U for September 2025 to August 2026 under section 1839(i)(5) of the Social Security Act and rounded to the nearest $1,000, the same calculation that reproduces every published year from 2020 to 2026. They are not official until CMS publishes them, and Tiers 2-4 depend by $1,000 on how CMS treats the October 2025 CPI-U that BLS never published (the top tier is fixed by statute through 2027 and carried forward unchanged).

~$209.50/month, up from a confirmed $202.90/month in 2026. That is the 2026 Medicare Trustees Report's intermediate estimate for 2027 — CMS's own actuaries, not a ustax.tools trend line. It is still a forecast: the binding figure arrives with the CMS Parts A & B fact sheet around November 2026.

On these figures, married-filing-separately filers who lived with their spouse during the lookback year would skip straight from Standard to Tier 4 once MAGI passes ~$112,000 — the same "no gradual climb" structure as every prior year. An MFS filer who lived apart from their spouse for the entire lookback year uses the regular single-filer table instead.

Still a hard cliff, regardless of the exact 2027 dollar thresholds — this structural feature of IRMAA is settled law, not something subject to projection. Crossing a boundary by even one dollar moves your ENTIRE MAGI into the next tier's full surcharge, not just the dollar over the line.

Typically November 2026, when CMS releases its annual Medicare Parts A & B Premiums and Deductibles fact sheet alongside SSA's updated POMS HI 01101.020 sliding-scale tables (the 2026 figures were confirmed the same way). This page will be updated with the official thresholds — and its "projected" framing removed — as soon as those sources publish.