How much will 2025 Medicare Part B and Part D premiums increase for each IRMAA bracket?

1. How IRMAA works and which tax year matters

IRMAA is a surcharge applied on top of Medicare Part B and Part D premiums for beneficiaries whose modified adjusted gross income (MAGI) from two years earlier exceeds statutory thresholds. For 2025, the Social Security Administration looks at 2023 tax returns to decide who pays IRMAA; the same income brackets apply to both Part B and Part D ^{[3] [2]}. CMS publishes the finalized IRMAA adjustment amounts each year; the 2025 Part B base premium and Part D IRMAA tables were released in CMS materials ^[1].

2. The 2025 baseline: standard Part B premium

CMS set the standard monthly Part B premium at $185.00 for 2025 — an increase of $10.30 from $174.70 in 2024 — and the Part B deductible and other cost figures were also updated in the CMS fact sheet ^[1]. That $185 is the starting point; higher‑income beneficiaries pay that plus an IRMAA surcharge ^{[1] [2]}.

3. The income thresholds that trigger IRMAA in 2025

For 2025, IRMAA applies once MAGI exceeds $106,000 for an individual filer and $212,000 for a joint filer; thresholds are indexed and change each year ^{[2] [3]}. Numerous outlets repeat that the IRMAA brackets are the same for Parts B and D and are based on the two‑year lag of tax data ^{[3] [4]}.

4. How much the surcharges add to premiums (what sources report)

Available sources describe that IRMAA is a sliding scale with multiple brackets and that the surcharge is added to the $185 Part B premium and to Part D plan premiums, with top surcharges reaching substantial amounts — for example, some summaries and charts show Part D IRMAA can add up to about $85.80 and Part B combined premiums for IRMAA payers can reach hundreds of dollars a month depending on bracket ^{[2] [5]}. CMS’s 2025 fact sheet provides the finalized Part B standard premium and states that 2025 Part D IRMAA amounts were released, but the specific per‑bracket dollar amounts and full bracket table are presented in CMS tables rather than quoted verbatim in the aggregated summaries provided here ^{[1] [2]}.

5. What reliable sources explicitly list versus what they omit

CMS explicitly gives the 2025 standard Part B premium ($185.00) and states it released Part D IRMAA amounts ^[1]. Consumer outlets (Kiplinger, NerdWallet, Humana) confirm the bracket start points and that surcharges are added on top of the standard premiums, and they note the five‑bracket sliding scale and top thresholds ^{[2] [3] [4]}. However, the search results provided do not include a clear, single citation with the complete per‑bracket surcharge dollar amounts reproduced directly from CMS tables within these snippets; therefore, a complete line‑by‑line breakdown of each IRMAA bracket’s exact added dollar amount for Parts B and D is not found in the current reporting supplied here ^{[1] [2]}.

6. Numbers reported elsewhere (context and caution)

Several secondary sites summarize ranges: one source shows Part B total premiums for IRMAA payers ranging broadly (examples cited elsewhere include Part B totals as high as several hundred dollars monthly and Part D surcharges up to roughly $85–$91 in some summaries) ^{[6] [5]}. These summaries reflect the sliding‑scale nature of IRMAA but vary in the exact figures and sometimes mix years; treat them as interpretive summaries that should be checked against CMS’s official tables ^{[6] [5]}.

7. Practical advice and disputes in the reporting

If you want the precise dollar increase for each IRMAA bracket in 2025, consult the CMS fact sheet and the Social Security Administration IRMAA tables, because secondary summaries repeat the structure but either paraphrase or present ranges rather than the official per‑bracket surcharge list ^{[1] [7]}. Sources note that IRMAA thresholds and surcharge amounts change annually with inflation and policy updates, and that appeals or income‑change procedures exist if your current income no longer reflects the two‑year‑old tax return ^{[2] [3]}.

Limitations: this analysis relies only on the provided search results. The CMS fact sheet confirms the $185 standard Part B premium and says Part D IRMAA amounts were released ^[1], and other sources confirm the bracket structure and MAGI year ^{[2] [3]}. A full, authoritative line‑by‑line table of each 2025 IRMAA bracket surcharge in dollars is not reproduced in the snippets supplied here — consult the CMS IRMAA tables or SSA POMS IRMAA sliding‑scale tables for the definitive per‑bracket dollar amounts ^{[1] [7]}.