Comparing Plans

Medicare Part A vs. Medicare Part B

Medicare Part A and Part B have a number of differences in cost, coverage, eligibility and more. Read a breakdown of Part A vs. Part B and get to better know your Medicare.

Medicare Part A and Part B are the two parts that make up “Original Medicare.”

Let’s take a look at Medicare Part A vs. Part B to see how they differ in terms of coverage, cost, eligibility and more. You can compare Part A, Part B and other types of Medicare plans as you decide which types of coverage are right for you.

A woman smiles as she speaks with her doctor

Find a $0 premium Medicare Advantage plan today.

Speak with a licensed insurance agent


What does Medicare Part A cover?

Medicare Part A is hospital insurance.

Part A covers many of the costs for your covered inpatient care at:

  • Hospitals
  • Mental health care facilities
  • Skilled nursing facilities
  • Inpatient care you receive as part of a clinical research study

Some of the items and services that Medicare Part A covers while you’re admitted as an inpatient can include:

  • Meals
  • Nursing care
  • A semi-private room
  • Drugs that are used as part of your inpatient treatment

Part A covers skilled nursing care you receive in a skilled nursing facility (SNF). The services that Part A covers can include (but aren’t limited to):

  • Meals
  • A semi-private room
  • Medications
  • Physical therapy, occupational therapy and/or speech-language pathology
  • Dietary counseling
  • Ambulance transportation (in certain circumstances)

Part A covers certain home health care services if you meet specific requirements, such as being homebound or having a doctor certify that you need intermittent skilled nursing care at home.

Part A also provides coverage for hospice care, which can include (but aren’t limited to) services such as:

  • Social work services
  • Grief counseling
  • Short term respite care
  • Prescription drugs that are used to control your symptoms or relieve pain 

Check with your doctor to learn more about how Medicare Part A may or may not cover your services.

How much does Medicare Part A cost in 2021?

Most people do not pay a premium for their Part A coverage. 

Medicare Part A premiums are based on how many years you worked and paid Medicare taxes.

  • Anyone who paid Medicare taxes for more than 40 quarters (the equivalent of 10 years) receives premium-free Part A.

  • Beneficiaries who only paid Medicare taxes for 30 to 39 quarters must pay $259 per month for Part A in 2021.

  • Anyone who paid Medicare taxes for fewer than 30 quarters must pay $471 per month in 2021.

Medicare Part A also includes a deductible of $1,484 per benefit period (in 2021), which is not annual. This means that you could potentially be required to pay the Part A deductible more than once in a year.

If you are admitted to a hospital for inpatient care, you must first meet your Part A deductible for each given benefit period before your Part A coverage kicks in.

If your hospital stay lasts for more than 60 days, you will pay the following Part A coinsurance costs in 2021:

  • Days 61-90: $371 per day for each benefit period
  • Days 91 and beyond: $742 per day for each lifetime reserve day
  • Beyond your lifetime reserve days: all hospital costs

You only have 60 lifetime reserve days to use in your lifetime. Once you use them, they are gone.

What is Medicare Part B and what does it cover?

Medicare Part B is medical insurance.

Part B covers outpatient care, which can include:

  • Doctor’s appointments
  • Physical therapy
  • Various types of rehab
  • Outpatient surgeries
  • Ambulance services

Part B covers durable medical equipment (DME), which can include things like wheelchairs, crutches, blood sugar test strips and other equipment that your doctor prescribes for use in your home.

Medicare Part B also covers some preventive care services, which can include (but aren’t limited to):

  • Diabetes screenings
  • Depression screenings
  • Mammograms
  • Bone mass/bone density measurements
  • Prostate cancer screenings
  • STI/STD screenings and counseling
  • Flu shots
  • Hepatitis B shots
  • Pneumococcal shots (pneumonia vaccine)

You should talk to your doctor or health care provider to find out more about how Medicare may or may not cover your tests, screenings or health care services and devices.

How much does Medicare Part B cost in 2021?

The standard Part B premium in 2021 is $148.50 per month.

Part B premiums are based on your reported modified adjusted gross income (MAGI) from two years prior if you're a higher income earner. So your 2021 Part B premiums may be based on your reported income from 2019. 

  • Individuals with a reported 2019 income of less than $88,000 per year and couples with a combined income of less than $176,000 per year pay the standard Part B premium of $148.50 per month in 2021.

  • Anyone with incomes above those thresholds pay more for their Part B coverage based on the Income-Related Monthly Adjusted Amount, or Medicare IRMAA.

The table below breaks down 2021 Medicare Part B premiums according to income. 

Medicare Part B IRMAA
2019 Individual tax return 2019 Joint tax return 2019 Married and separate tax return 2021 Part B monthly premium

$88,000 or less

$176,000 or less

$88,000 or less


More than $88,000 and up to $111,000

More than $176,000 and up to $222,000



More than $111,000 up to $138,000

More than $222,000 up to $276,000



More than $138,000 up to $165,000

More than $276,000 up to $330,000



More than $165,000 up to $500,000

More than $330,000 up to $750,000

More than $88,000 up to $412,000


More than or equal to $500,000

More than or equal to $750,000

More than or equal to $412,000


The premiums for Part A and Part B can potentially increase every year. 

Part B also includes a deductible, which is $203 per year in 2021.

After you meet your Part B deductible, you typically pay 20 percent of the Medicare-approved amount for most covered services. This is called the Part B coinsurance or copayment.

Who is eligible for Medicare Part A and Part B?

In order to be eligible for Medicare Part A and/or Part B, you must meet each of the following eligibility requirements:

  • You are at least 65 years old OR have a qualifying disability

  • You are a U.S. citizen OR a permanent legal resident of at least five consecutive years

  • You are eligible for retirement benefits from either the Social Security Administration or the Railroad Retirement Board, OR you have been receiving disability benefits from either one for at least two years

As mentioned above, Medicare Part B is optional. 

How do I sign up for Medicare Part A and Part B?

Some people are automatically enrolled in Medicare Part A and Part B. You are typically automatically enrolled if you’re already receiving Social Security or Railroad Retirement Board retirement benefits when you turn 65.

If you’re under 65 and eligible for Medicare due to a disability, you’ll be automatically enrolled the 25th month you’ve been receiving Social Security disability benefits.

  • If you are eligible for premium-free Part A, you will receive your red, white and blue Medicare card and welcome packet in the mail approximately three months before your 65th birthday.

    You will also typically be automatically enrolled in both Part A and Part B, with your coverage beginning on the first day of your birthday month. 

    Although you may be automatically enrolled in Part B, you may opt out of coverage before your first monthly premium comes due. 

  • If you aren’t automatically enrolled, you must take steps to manually enroll in both Part A and B.

    When you first become eligible for Medicare, you will be granted an Initial Enrollment Period (IEP). This 7-month period begins three months before you turn 65, includes the month of your birthday and continues on for three more months. You may apply for Medicare Part A and B during this time. 

  • You may also be able to sign up during a Special Enrollment Period if you qualify based on certain specific circumstances

*Note: If you do not sign up for Part B when you first become eligible, you may be subject to a Part B late enrollment penalty if you choose to sign up at a later time.

Medicare Advantage plans can offer benefits that Original Medicare doesn’t cover

Original Medicare doesn’t typically cover prescription drugs. Part A and Part B also don’t cover certain health care services such as:

If you want coverage for prescription drugs or other health services not covered by Original Medicare, you may have to pay entirely out of pocket.

Some Medicare Advantage plans (Medicare Part C), however, may offer coverage for services not covered by Original Medicare.

Medicare Advantage plans are sold by private insurance companies and cover everything that Part A and Part B cover.

Most Medicare Advantage plans offer prescription drug coverage. Some plans cover things like bathroom grab bars and may offer allowances for things like glasses and hearing aids.

Part C plan availability can vary from one location to the next. A licensed insurance agent can help you compare Medicare Advantage plans that may be available where you live.

Find Medicare Advantage plans in your area

Compare Plans

Or call TTY Users: 711 to speak with a licensed insurance agent. We accept calls 24/7!


About the author

Christian Worstell is a licensed insurance agent and a Senior Staff Writer for He is passionate about helping people navigate the complexities of Medicare and understand their coverage options.

His work has been featured in outlets such as Vox, MSN, and The Washington Post, and he is a frequent contributor to health care and finance blogs.

Christian is a graduate of Shippensburg University with a bachelor’s degree in journalism. He currently lives in Raleigh, NC.

Where you've seen coverage of Christian's research and reports:

MarketWatch logo

Yahoo Finance logo 


WebMD Logo

South Florida Sun Sentinel Logo Logo

Deseret News Logo

Healthcare Finance Logo