If you're on Original Medicare in 2025, two deductibles shape how much you pay before your coverage starts doing the heavy lifting. The Centers for Medicare & Medicaid Services (CMS) adjusts these amounts annually, and both went up for 2025. Understanding exactly how each deductible works — and where the real financial exposure lies — can help you plan your healthcare spending and decide whether supplemental coverage makes sense for your situation.
The Medicare Part B deductible for 2025 is $257 per calendar year. That's an increase of $17 from the $240 deductible that applied in 2024. Part B covers outpatient care: doctor visits, preventive services, lab work, durable medical equipment, and outpatient surgery, among other things. Once you've paid $257 out of pocket for covered Part B services in a calendar year, Medicare picks up 80% of the Medicare-approved amount for most services — and you're responsible for the remaining 20% coinsurance. That 20% has no annual cap under Original Medicare alone, which is a critical detail many beneficiaries don't realize until they face a major procedure.
The Part A deductible is where things get more complicated — and potentially more expensive. In 2025, the Part A deductible is $1,676 per benefit period. This is not an annual deductible. A benefit period begins the day you're admitted to a hospital or skilled nursing facility and ends when you've been out of that facility for 60 consecutive days. If you're hospitalized, recover at home for 45 days, and then are admitted again, that's a new benefit period — and a new $1,676 deductible. There is no limit to how many benefit periods you can have in a single year, which means a beneficiary with multiple hospitalizations could theoretically owe this deductible several times over. For 2024, the Part A deductible was $1,632, so the 2025 increase is $44.
Beyond the deductible, Part A also includes coinsurance for longer hospital stays. In 2025, days 1 through 60 of a hospital stay are covered after you pay the deductible. From days 61 to 90, you owe $419 per day in coinsurance. If your stay extends beyond 90 days, you can draw on your 60 lifetime reserve days, but those come with a $838-per-day coinsurance charge. Once those lifetime reserve days are exhausted, Medicare pays nothing for inpatient hospital care. These numbers underscore why a single extended hospitalization can create serious financial strain for someone on Original Medicare without supplemental coverage.
For skilled nursing facility (SNF) care — the kind of short-term rehabilitation stay that often follows a hospitalization — Part A covers the first 20 days in full after you've met the inpatient hospital deductible and had a qualifying hospital stay of at least three days. From days 21 through 100, you owe $209.50 per day in coinsurance in 2025. After day 100, Medicare pays nothing for SNF care. This is a common source of financial shock for beneficiaries and their families who assume Medicare covers long-term nursing home costs — it does not, except in this limited post-acute window.
The standard Medicare Part B premium in 2025 is $185.00 per month, separate from the deductible. Higher-income beneficiaries pay more through the Income-Related Monthly Adjustment Amount (IRMAA). If your modified adjusted gross income from two years prior (meaning your 2023 tax return affects your 2025 premium) exceeded $106,000 for an individual or $212,000 for a married couple filing jointly, you'll pay a surcharge on top of the standard premium. The highest IRMAA tier in 2025 brings the Part B premium to $628.90 per month for individuals with income above $500,000. If you've had a significant income change — retirement, loss of a spouse, or reduced work hours — you can request a review using IRS Form SSA-44 to potentially lower your IRMAA tier.
One of the most effective ways to manage deductible exposure is through a Medicare Supplement Insurance plan, commonly called Medigap. These are standardized private insurance plans sold alongside Original Medicare. Medigap Plan G, one of the most popular options available to beneficiaries who became eligible for Medicare on or after January 1, 2020, covers the Part A deductible, Part A coinsurance, Part B coinsurance, and several other cost-sharing items — but not the Part B deductible. Medigap Plan N covers similar costs but requires copays of up to $20 for some office visits and up to $50 for emergency room visits. The now-discontinued Plan F, still available to those who were Medicare-eligible before 2020, covered both deductibles in full. Medigap premiums vary significantly by insurer, your age, and where you live, so comparing plans through Medicare.gov's plan finder or your State Health Insurance Assistance Program (SHIP) counselor is worth the time.
Medicare Advantage plans — the private insurance alternative to Original Medicare — handle deductibles differently. Many Medicare Advantage plans in 2025 have $0 deductibles for medical services, which sounds appealing, but they typically use copays and coinsurance structures instead, and they restrict you to provider networks. The out-of-pocket maximum for Medicare Advantage plans in 2025 is capped at $9,350 for in-network services and $14,000 for combined in- and out-of-network costs — protections that Original Medicare alone does not offer. Whether a Medicare Advantage plan saves you money compared to Original Medicare plus a Medigap plan depends heavily on how much care you use, which doctors you see, and what your local plan options look like.
If you have limited income and assets, you may qualify for programs that help cover Medicare cost-sharing. The Medicare Savings Programs (MSPs) — administered through your state Medicaid office — can pay your Part B premium, and in some cases your deductibles and coinsurance, depending on your income level. The four MSP tiers are Qualified Medicare Beneficiary (QMB), Specified Low-Income Medicare Beneficiary (SLMB), Qualifying Individual (QI), and Qualified Disabled and Working Individuals (QDWI). QMB, the most comprehensive tier, covers Part A and Part B premiums, deductibles, and coinsurance for beneficiaries with income at or below 100% of the federal poverty level. In 2025, that's roughly $1,255 per month for an individual. Applying through your state Medicaid office costs nothing and can result in substantial savings.
The Annual Enrollment Period (AEP), which runs October 15 through December 7 each year, is your primary window to switch between Original Medicare and Medicare Advantage, or to change Medicare Advantage plans. Changes made during AEP take effect January 1. If you're already in a Medicare Advantage plan and want to return to Original Medicare, you can also do so during the Open Enrollment Period (OEP), which runs January 1 through March 31 — but be aware that switching back to Original Medicare mid-year may make it harder to get a Medigap plan if you're not in a guaranteed issue situation, since insurers in most states can use medical underwriting to deny or price your application. Reviewing your coverage each fall with these deductible amounts in mind is one of the most practical steps you can take to avoid surprise costs in the year ahead.