Understanding Medicare Part B
What you need to know
The basics
Medicare Part B is also known as Medical Insurance. Part B helps cover two types of services:
- Medically necessary services: Services or supplies that meet accepted standards of medical practice to diagnose or treat your condition.
- Preventive services: Health care to help prevent illness (like the flu) or detect it at an early stage when treatment is likely to work best. See Medicare.gov’s list of preventive services to learn more.
Note: You pay nothing for most preventive services if you get them from a provider who accepts Part B insurance.
If you're in a Medicare Advantage or other Medicare plan, your plan may have different rules. But your plan must give you at least the same coverage as Original Medicare.
Visit Medicare.gov for a complete list of services Medicare Part B covers.
Medicare coverage
Part A Inpatient medical needs
Part B Outpatient medical needs
Part D Prescription medicines
Medicare Part B coverage
Covered drugs
Medicare Part B covers a limited number of outpatient prescription drugs under certain conditions. Outpatient drugs are those given at clinics, hospitals or other facilities for a person who does not stay overnight.
These include the following Part B drugs:
- Oral (by mouth) anti-nausea drugs
- Drugs you give yourself in hospital outpatient settings (like some injections)
- New Alzheimer’s drugs
- Drugs approved and used for HIV PrEP (preexposure prophylaxis)
- Drugs used with an item of durable medical equipment (DME) (like nebulized drugs)
- Some antigens, which help your body build up an immune response (like allergy shots)
- Preventive shots (vaccinations)*
- Transplant/Immunosuppressive drugs
- Injected osteoporosis drugs
- Erythropoiesis-stimulating agents, which help your bone marrow make more red blood cells
- Blood clotting factors, which help your blood clot better
- Injectable and infused drugs (like insulin or chemotherapy infused with a pump)
- Oral cancer drugs
- Oral end-stage renal disease (ESRD) drugs
- Parenteral and enteral nutrition (intravenous and tube feeding)
- Intravenous immunoglobulin (IVIG), as well as other items and services that help you get IVIG at home
* You pay nothing for COVID-19 vaccines or for flu or pneumococcal shots. If you are at intermediate or high risk for hepatitis B, you also pay nothing for these shots. Your Part B deductible also doesn’t apply to these drugs.
Covered durable medical equipment
Part B covers medically necessary durable medical equipment (DME) if your Medicare-enrolled doctor or other health care provider prescribes it for use in your home.
DME is defined as equipment that is:
- Durable (can withstand repeated use)
- Typically only useful to someone who is sick or injured
- Used in your home
- Expected to last at least three years
- Used for a medical reason
You must rent most items, but in some circumstances, you can also buy them. Some items become your property after you’ve made a certain number of rental payments. For more information visit Medicare.gov
Medicare-covered DME includes, but isn’t limited to:
- Blood sugar meters and test strips
- Canes, crutches and walkers
- Commode chairs
- Continuous passive motion machines, devices and accessories
- Continuous positive airway pressure (CPAP) machines
- Hospital beds
- Infusion pumps and supplies
- Nebulizers and nebulizer drugs
- Oxygen equipment and accessories
- Patient lifts
- Pressure-reducing support surfaces
- Suction pumps
- Wheelchairs and scooters
Important insulin benefit
Your cost for a month’s supply of insulin for your insulin pump can’t be more than $35 if one or more of the following are true:
- You use an insulin pump that's covered under Part B's DME benefit
- You get your covered insulin through a Medicare Advantage plan
In either of these cases, the Part B deductible won't apply.
If you get a three-month supply of Part B-covered insulin, your costs can't be more than $35 for each month's supply. This means you'll typically pay no more than $105 for a three-month supply of covered insulin.
If you have Part B and Medicare Supplement Insurance (Medigap) that pays your Part B coinsurance, your Medigap plan should cover the cost for insulin.
Medicare Part B costs
You may have a deductible for Part B-covered services and supplies before Medicare begins to pay its share. Your deductible is the amount you pay for health care services before your plan begins to pay.
After you pay your deductible, you may have a coinsurance on your Part B drugs. Coinsurance is a percentage of a covered health care service that you pay after you’ve met your deductible. Your coinsurance amount can sometimes change depending on where you receive Part B drug, the type of Part B drug you’re getting and your prescription drug's price.
In most cases, after you meet the Part B deductible, you pay up to 20% of the Medicare-approved amount for covered Part B prescription drugs and DME.
Visit the Medicare.gov outpatient drugs page and DME page for more cost info.
Make sure your provider accepts Medicare insurance
Check that your doctors, other health care providers and DME suppliers are enrolled in Medicare. It’s important to ask a supplier if they participate in Medicare before you get your DME. If they do participate, they can only charge you the coinsurance and Part B deductible for the Medicare-approved amount. If DME suppliers aren’t participating, there’s no limit on the amount they can charge you.
