What are the 2025 Medicare Part B and Part D standard premiums and deductibles?

1. The headline numbers: Part B premium and deductible for 2025

CMS set the 2025 standard monthly premium for Medicare Part B at $185.00 — an increase of $10.30 from the $174.70 standard premium in 2024 — and established the Part B annual deductible at $257 for 2025, up $17 from $240 in 2024, with CMS attributing the rise mainly to projected price changes and assumed utilization increases ^[1]. Some beneficiaries, however, may pay less than the $185 standard premium because the law limits how much a current enrollee’s Part B premium can increase in a year to the Social Security cost‑of‑living adjustment, an important caveat highlighted by the Railroad Retirement Board and other agencies ^{[4] [5]}.

2. Part D is not one number: plan variation, average premium, and the deductible cap

Medicare Part D costs are set by individual prescription drug plans, so monthly premiums vary plan to plan and many enrollees pay nothing extra beyond their Part B premium depending on plan choice, but CMS and aggregators report a 2025 average Part D premium around $46.50 — a useful working figure though not universal for all enrollees ^[2]. The statutory maximum deductible for Part D in 2025 was $590 — plans can and often do set lower or no deductibles, but no plan may charge a deductible higher than that cap (the 2026 cap was raised to $615, underscoring year‑to‑year movement) ^{[3] [6]}.

3. Who pays more: IRMAA and the income squeeze

Higher‑income beneficiaries pay income‑related monthly adjustment amounts (IRMAA) on both Part B and Part D in addition to the standard premiums; for 2025 Part B income‑adjusted premiums ranged from $259.00 to $628.90 depending on MAGI, and CMS estimates roughly 8 percent of beneficiaries pay these higher amounts ^[4]. The IRMAA surcharges for Part B in 2025 add from tens to several hundred dollars to the base premium, and Part D carries a parallel surcharge structure based on the same IRS income thresholds and a two‑year lookback to tax returns ^{[2] [4]}.

4. The practical picture for beneficiaries and policy context

Nearly 99 percent of beneficiaries pay no Part A premium because they have sufficient Medicare‑covered employment history, but they face the Part A inpatient deductible ($1,676 in 2025) and Part B cost sharing (20% coinsurance after the deductible) — framing why Part B and Part D changes matter to out‑of‑pocket exposure ^[1]. Advocacy groups and resources stress that many beneficiaries can lower drug costs by choosing plans with low or no deductibles, by qualifying for state Extra Help, or by contesting IRMAA determinations if circumstances changed, reflecting CMS, SSA, and nonprofit guidance on mitigation options ^{[7] [8]}.

5. Limits of available reporting and what is not asserted

CMS and related sources provide authoritative calendar‑year figures for the standard Part B premium ($185) and deductible ($257) and for Part D average premiums and statutory deductible caps, but plan‑level variation for Part D premiums and deductibles means any individual’s true bill depends on the specific PDP or Medicare Advantage drug benefit chosen — a fact the sources emphasize and which prevents a single definitive Part D “standard” beyond the statutory cap and averages ^{[2] [3]}. Where sources note legal protections (cost‑of‑living hold‑back for current enrollees) or percentage estimates of IRMAA payers, those are reported here as given rather than extrapolated to individual circumstances ^{[4] [9]}.