What Is Medicare Part B, and What Does It Cover?

Medicare Part B is part of Original Medicare. Part B is an optional medical insurance plan for adults 65 and older, younger people who have disabilities, and people with end-stage renal disease (permanent kidney failure). It helps pay for preventive care, like flu shots and cancer screenings, and medically necessary services such as doctor visits, lab tests, medical equipment, and outpatient procedures.

In 2024, the standard Part B premium is $174.70 per month, but some people with higher incomes may pay more.^[1]

What does Medicare Part B cover?

If you decide to enroll in it — you can choose not to enroll — Medicare Part B covers a wide range of medically necessary outpatient services and preventive care, such as:

• Doctor visits: Doctor visits for diagnosis, treatment, and consultations with specialists qualify for coverage through Part B.

• Outpatient procedures: Part B covers many outpatient surgeries and procedures, such as X-rays, lab tests, stitches, casts, and endoscopies.

• Certain prescription medications: If they’re part of your service or procedure, Part B will cover certain prescription drugs.

• Medical equipment: Part B helps pay for things like blood sugar monitors, wheelchairs, walkers, hospital beds, and CPAP machines if your doctor prescribes it.

• Ambulance services: If it’s medically necessary for you to travel by ambulance, airplane, or helicopter, Part B would pay for your transportation. In some cases, it may cover non-emergency ambulance services, too.

• Preventative care: Part B covers many screenings and preventive services like flu shots, mammograms, colonoscopies, bone density scans, and annual wellness visits.

• Clinical research: Part B covers certain office visits and tests as part of qualifying clinical research studies.

• Mental health care: You can use your Part B coverage for outpatient mental health, care like therapy, counseling, and partial hospitalization programs.

• Home healthcare: In limited situations, Part B covers someone to care for you in your own home.

Other parts of Medicare

Part B is an important component of Medicare, but it’s just one piece of the program. Other parts of Medicare include:^[2]

• 

  Part A (hospital insurance)

  Part A covers things like inpatient stays, skilled nursing facility care, hospice care, and some home healthcare. It doesn’t cover outpatient visits like Part B.

• 

  Part C (Medicare Advantage)

  As an alternative to Original Medicare, Part C bundles Part A, Part B, and (usually) Part D. Private companies offer Medicare Advantage plans, and they can include extra benefits like vision, hearing, and dental services that Part B doesn’t cover.

• 

  Part D (prescription drug coverage)

  Part D covers medications that Part B won’t pay for. Private insurance companies run these programs.

• 

  Medigap (Medicare supplemental insurance)

  Medigap plans are available from private insurance companies in addition to Original Medicare. Plans help cover your share of costs like copayments, co-insurance, and deductibles. You might find Medigap plans with names like Plan G or Plan K.

What won’t Medicare Part B cover?

Medicare Part B is limited and leaves some gaps in your healthcare coverage. Some examples of what Part B doesn’t cover include:

• Long-term care: Part B doesn’t cover extended nursing home stays or assisted living.

• Routine dental, vision, and hearing care: Part B doesn’t cover dental care, eyeglasses, or hearing aids. Some exceptions apply, like vision care after cataract surgery.

• Most prescription drugs: Part B only covers certain outpatient drugs under limited conditions. For most prescriptions, you need Part D.

• Cosmetic surgery: Unless medically necessary, Part B doesn’t pay for procedures like nose reshaping.

• Care outside of the U.S.: Medicare doesn’t cover you if you’re outside the U.S.

How much Medicare Part B costs

Medicare aims to provide low-cost health insurance for seniors on limited incomes. But you’ll have to kick in some of your own cash for Part B, similar to employer-sponsored plans and Affordable Care Act Plans (also called Obamacare) plans. Here’s a breakdown of key costs as of 2024.

Medicare Part B premiums

Your tax-filing status and annual income determine how much you pay for Medicare Part B. Your cost is usually deducted from your Social Security benefits. Most people pay $174.70 per month, which is the cheapest premium available. If you earn a higher income, you may pay more, as shown here.

Medicare Part B deductibles

The annual Part B deductible is $240. You pay this amount out of your own pocket before Medicare starts covering services.

Unlike Part A, in which a deductible applies each time you’re hospitalized, you’ll only pay your Part B deductible once each year. The deductible resets each year.

Medicare Part B co-insurance

Co-insurance comes into play after you meet the deductible. For most doctor services, outpatient therapy, and durable medical equipment, you’ll pay 20% of the cost.

Unfortunately, Medicare Part B doesn’t limit the annual co-insurance costs.

How to enroll in Medicare Part B

To enroll in Medicare Part B, you’ll apply with the Social Security Administration. The program encourages you to apply online, but you can also send your application by mail or fax.^[3] After signing up, you’ll get a welcome package, including your Medicare card, in the mail.

Enrollment periods

Medicare offers three enrollment periods throughout the year:

• Initial Enrollment Period: It lasts for seven months and includes the three months before you turn 65, the month you turn 65, and the three months after your 65th birthday. 

• General Enrollment Period: It runs from Jan. 1–March 31 each year.

• Special Enrollment Period: It has a limited window if you lost Medicaid or employer healthcare coverage, were incarcerated, or meet other specific conditions.

If you don’t enroll during your Initial Enrollment Period and don’t qualify for a Special Enrollment Period, you may have to pay a penalty — and it isn’t a one-time fee. You’ll pay an extra 10% on top of your monthly premium for every year that you fail to sign up for Part B.

Eligibility requirements

You must meet certain eligibility requirements to enroll in Medicare Part B:^[3]

• Age 65 or older

• U.S. resident

• U.S. citizen or permanent legal resident who’s lived in the U.S. for at least five years before applying

If you’re younger than 65, you may be eligible for Part B if you have Social Security disability insurance for 24 months, have end-stage renal disease, or have Lou Gehrig’s disease (also called amyotrophic lateral sclerosis, or ALS).

Original Medicare vs. Medicare Advantage plans

You can choose between two main paths for your Medicare coverage: Original Medicare or Medicare Advantage. The federal government runs Original Medicare, while private insurance companies offer Medicare Advantage as an alternative to Original Medicare.

What is Original Medicare?

Original Medicare includes Part A and Part B. Together, it covers inpatient hospital stays, skilled nursing facility care, hospital care, some home healthcare, doctor visits, outpatient care, and medical supplies. You can see any provider that accepts Medicare, and you have the option to add Part D prescription drug coverage.

What is Medicare Advantage?

Also known as Part C, Medicare Advantage is an “all-in-one” plan available through private insurers that bundles Part A, Part B, and usually Part D benefits. You typically need to see doctors in the plan’s network, but you may pay less from your own pocket than with Original Medicare.

What is Medicare supplemental insurance (Medigap)?

Medigap is a supplemental insurance policy that helps pay for costs Original Medicare doesn’t cover, like your Part A and Part B deductibles, copays, and co-insurance. Private insurers offer Medigap plans with letter names (like Plan G or Plan K).

If you opt for Original Medicare and expect high medical costs, a Medigap plan may be a good idea since Part B doesn’t have a cap on how much you’ll pay out of pocket.

Medicare Part B FAQs