Editorial note: Figures on this page reflect the 2026 Medicare program year and are cross-referenced against the official Centers for Medicare & Medicaid Services (CMS) publications. Always confirm current numbers before making enrollment decisions.
Last Reviewed: July 2026
What Part B covers
Part B is the "medical insurance" side of Original Medicare. It helps pay for services you receive from doctors and outpatient providers. For the full official list, see the Medicare.gov "What Part B covers" page.
- Doctor visits (primary care and specialists).
- Preventive care like flu shots, cancer screenings, and the annual wellness visit.
- Outpatient surgery and procedures.
- Durable medical equipment (wheelchairs, walkers, oxygen, CPAP).
- Laboratory services, X-rays, and most imaging.
- Ambulance services (in qualifying situations).
- Mental health services, including therapy and psychiatric care.
- Some limited outpatient prescription drugs (e.g., certain infusions).
What Part B costs
- Monthly premium: $202.90 for most people in 2026. Higher earners pay more (see IRMAA below).
- Annual deductible: $283 per year.
- Coinsurance: after the deductible is met, you typically pay 20% of the Medicare-approved amount for most covered services, and Medicare generally pays 80%.
- No out-of-pocket maximum: that 20% is unlimited — a key reason many beneficiaries add a Medicare Supplement (Medigap) policy or consider Medicare Advantage.
Confirm current figures at Medicare.gov.
Late enrollment penalties
What is IRMAA?
IRMAA stands for the Income-Related Monthly Adjustment Amount. In plain English: if your reported income is above certain thresholds, you'll pay a higher Part B (and Part D) premium. The Social Security Administration determines this based on your tax return from two years ago. The current brackets are published on Medicare.gov.
Eligibility & enrollment
- Eligible at age 65, or after 24 months on SSDI, or immediately with ALS or ESRD.
- Auto-enrolled if you're already receiving Social Security when you turn 65 — otherwise you must sign up through the Social Security Administration.
- Your Initial Enrollment Period is the 7 months around your 65th birthday.
- If you're still working with creditable employer coverage, you may be able to delay Part B without penalty — confirm your plan's creditable status in writing before delaying.
- After qualifying employer coverage ends, you generally have an 8-month Special Enrollment Period to sign up without a late-enrollment penalty.
Sign-up runs through the Social Security Administration, not the health-insurance marketplace.
Preventive services Part B covers at 100%
- One-time "Welcome to Medicare" visit in your first 12 months of Part B.
- Annual wellness visit.
- Flu, pneumonia, COVID-19, and Hepatitis B shots.
- Cardiovascular, diabetes, and cancer screenings when medically indicated.
- Depression and alcohol misuse screenings.
Common mistakes to avoid
- Assuming COBRA, retiree, or ACA marketplace coverage counts as 'creditable' — often it does not, and delaying Part B can trigger a lifetime penalty.
- Missing the 8-month Special Enrollment Period after qualifying employer coverage ends.
- Not budgeting for IRMAA if a one-time income event (like a Roth conversion or home sale) pushes you above a threshold two years before.
- Overlooking the once-per-lifetime 'Welcome to Medicare' preventive visit in your first 12 months of Part B.
- What: Part B helps cover outpatient care — doctors, preventive services, durable medical equipment, and mental health.
- Why it matters: Part B works together with Part A to form Original Medicare, and it's typically required before you can enroll in Medicare Supplement (Medigap) or Medicare Advantage.
- How: Enroll through the Social Security Administration during your Initial Enrollment Period; the standard premium is income-adjusted; there is no out-of-pocket cap without supplemental coverage.
Medicare has neither reviewed nor endorsed this information. For a complete list of plans in your area, call 1-800-MEDICARE (TTY: 1-877-486-2048).