Medicare Part A covers hospital and inpatient care, while Part B covers doctor visits, outpatient services, and preventive care. Together, they form what’s known as Original Medicare, and understanding exactly what falls under each part helps you anticipate both your coverage and your costs.
What Part A Covers
Part A is hospital insurance. It pays for care you receive as an inpatient, meaning you’ve been formally admitted to a facility. This includes semi-private rooms, meals, general nursing, medications administered during your stay, and other hospital services tied to your treatment. For 2025, you pay a $1,676 deductible per benefit period before Part A kicks in.
Part A also covers three other major categories: skilled nursing facility care, home health services, and hospice care.
Skilled Nursing Facility Care
If you need daily skilled care like IV medications or physical therapy after a hospital stay, Part A covers up to 100 days in a skilled nursing facility per benefit period. There’s an important catch: you typically need a qualifying inpatient hospital stay of at least 3 consecutive days first, and you must enter the facility within 30 days of leaving the hospital. Time spent under observation or in the ER does not count toward those 3 days, even if you stayed overnight.
The first 20 days cost you nothing beyond your Part A deductible. Days 21 through 100 come with a daily coinsurance of $217 in 2026. After day 100, Medicare stops paying entirely. Some Medicare Advantage plans and certain doctor-led care organizations can waive the 3-day hospital stay requirement, so it’s worth asking before you assume you don’t qualify.
Home Health Services
Medicare covers part-time skilled nursing and therapy in your home if you’re considered “homebound,” meaning leaving your home is a major effort due to illness or injury, requiring a wheelchair, walker, cane, special transportation, or help from another person. Coverage allows up to 8 hours of combined skilled nursing and home health aide services per day, with a maximum of 28 hours per week. Short bursts of more intensive care (up to 35 hours weekly) are possible if your provider deems it necessary. If you need full-time skilled care, home health services won’t cover it.
Hospice Care
For patients with a terminal illness, Part A covers hospice care with very low out-of-pocket costs. This includes pain management medications (with a copay of no more than $5 per prescription), emotional and spiritual support, family counseling, and short-term respite care so caregivers can take a break. Respite stays last up to 5 days at a time, and you pay roughly 5% of the Medicare-approved amount for them.
What Part B Covers
Part B is medical insurance. It handles the outpatient side of your care: doctor visits, lab tests, diagnostic imaging, outpatient surgeries, and medically necessary supplies. The standard monthly premium for 2025 is $185, and the annual deductible is $257. After you meet that deductible, you generally pay 20% of the Medicare-approved amount for most services.
Specific covered services include ambulance transport, outpatient mental health care (individual and group therapy, psychiatric evaluations, partial hospitalization programs), and a limited set of outpatient prescription drugs. Part B also covers durable medical equipment when your doctor orders it. That category includes wheelchairs and scooters, walkers, canes, crutches, hospital beds, oxygen equipment, CPAP machines, blood sugar monitors and test strips, and infusion pumps. You pay 20% coinsurance on equipment from a supplier that accepts Medicare assignment.
Preventive Services at No Cost
One of Part B’s most valuable features is its preventive care coverage. You pay nothing for most preventive services when you see a provider who accepts assignment. The list is extensive:
- Cancer screenings: mammograms, colonoscopies, lung cancer screenings, cervical and vaginal cancer screenings, prostate cancer screenings, and stool-based colorectal tests
- Cardiovascular care: cholesterol and lipid screenings, plus behavioral counseling for heart disease risk
- Diabetes: diabetes screenings, self-management training, medical nutrition therapy, and a diabetes prevention program
- Vaccines: flu shots, COVID-19 vaccines, pneumococcal shots, and hepatitis B shots
- Mental health: depression screenings, alcohol misuse screenings and counseling, tobacco cessation counseling
- Other screenings: HIV, hepatitis B and C, glaucoma, bone density, obesity counseling, and sexually transmitted infection screenings
Every Medicare beneficiary also gets a one-time “Welcome to Medicare” preventive visit shortly after enrolling, plus a yearly wellness visit to update your prevention plan with your doctor. These visits are designed to catch problems early, and they cost you nothing.
What Original Medicare Does Not Cover
The gaps in Parts A and B matter just as much as the coverage. Original Medicare does not pay for routine dental care, including cleanings, fillings, extractions, and dentures. It doesn’t cover eye exams for prescription glasses, hearing aids, or exams to fit them. And despite what many people assume, it does not cover long-term care, meaning ongoing custodial help with daily activities like bathing or dressing when you don’t also need skilled medical care.
These are the gaps that lead many people to add supplemental coverage. Medigap (Medicare Supplement) plans can help with cost-sharing like deductibles and coinsurance. Medicare Advantage plans, which replace Original Medicare, sometimes include dental, vision, and hearing benefits. Standalone Part D plans cover outpatient prescription drugs, which Parts A and B largely do not.
How Costs Break Down in Practice
Most people don’t pay a premium for Part A if they or a spouse paid Medicare taxes for at least 10 years. Part B’s $185 monthly premium in 2025 is automatically deducted from Social Security checks for most enrollees, though higher earners pay more through income-related surcharges.
After your deductibles, the cost-sharing structure is straightforward but can add up. Part B’s 20% coinsurance has no annual cap in Original Medicare, which means a major illness or surgery could leave you responsible for a significant share of costs. That’s the primary reason many beneficiaries carry supplemental insurance. For Part A, the $1,676 hospital deductible resets with each benefit period (which begins when you’re admitted and ends after you’ve been out of a hospital or skilled nursing facility for 60 consecutive days), so multiple hospitalizations in a year could mean paying that deductible more than once.