Medicare Part B is the portion of Medicare that covers most doctor visits and other outpatient medical services. It also covers durable medical equipment and preventive services.
Most people pay a premium of $170.10 per month in 2022 ($164.90 in 2023). You might pay more if your income exceeds certain thresholds.
Here’s what you should know about Medicare Part B.
Medicare Part B eligibility
You become eligible for Medicare Part B at age 65 and should sign up during the initial enrollment period, the seven-month period around your birthday[0]. Hitting the deadline is important. If you delay, you may face an expensive penalty.
What does Medicare Part B cover?
Original Medicare is made up of two parts: Part A and Part B. Part A generally covers care at hospitals and some skilled nursing facilities. Part B generally covers care and services delivered at clinics or other outpatient locations.
Medicare Part B covers two kinds of services: medically necessary outpatient care and preventive services[0].
Medically necessary outpatient care
Medicare Part B covers a variety of outpatient care and services when they’re medically necessary. According to the Centers for Medicare & Medicaid Services, medically necessary services are “services or supplies that are needed to diagnose or treat your medical condition and that meet accepted standards of medical practice.”
After you’ve paid your Medicare Part B deductible for the year, Part B generally pays for 80% of covered medically necessary services. You’re responsible for a 20% Part B coinsurance for most covered services.
Here are some examples of medically necessary services covered by Medicare Part B:
Outpatient services like visits to a health care provider at an office or clinic and services such as X-rays, stitches and casts that you get at a hospital without being admitted as an inpatient.
Ambulance services to the nearest appropriate medical facility to get medically necessary care, if traveling in any other vehicle could endanger your health.
Prescription drugs you don’t give yourself, like infusions or injections you have to get at a doctor’s office or hospital outpatient department. (Most prescription drugs, which you take yourself, are covered by Medicare Part D or Medicare Advantage plans that include prescription drug coverage instead.)
Mental health services like therapy or counseling, psychiatric evaluations, medication management and partial hospitalization for mental health issues. (Part A covers mental health care if you’re admitted as an inpatient.)
Medicare preventive services
Medicare Part B also covers preventive care and services including certain disease and cancer screenings, tests, shots and counseling.
While most medically necessary services require a 20% Part B coinsurance, you don’t pay anything for most preventive services.
Here are a few examples of preventive services for which you’ll pay nothing under Medicare Part B[0]:
Screening colonoscopies (you may need to pay coinsurance for additional services like polyp removal or barium enemas).
Certain preventive services are limited to certain sexes and/or have conditions on how often Medicare covers them. To pay nothing for some services, you need to get them from a health care provider who accepts Medicare assignment. You can find specific details for how individual services are covered at medicare.gov/coverage.
What Part B doesn’t cover
There are a number of services Medicare Part B doesn’t cover. You’d be responsible for paying for these services out of pocket unless you have other insurance that covers them.
Here are a few examples of services not covered by Medicare Part B:
You need to pay the premiums each month, regardless of what care or services you get.
You need to pay your deductible out of pocket before Part B will start paying for most covered services.
You pay a 20% coinsurance for most medically necessary services covered by Part B, but there’s no coinsurance for most preventive care.
Most people pay the standard Medicare Part B monthly premium: $170.10 per month in 2022 ($164.90 in 2023). (Premium amounts usually change from year to year.)
High-income beneficiaries may pay more than that. If your modified adjusted gross income from two years ago is above a certain threshold, you also need to pay an income-related monthly adjustment amount, or IRMAA.
For 2022, beneficiaries whose 2020 income exceeded $91,000 (individual return) or $182,000 (joint return) will pay a premium amount ranging from $238.10 to $578.30, depending on income. In 2023, the thresholds are $97,000 and $194,000 based on 2021 income, and premiums range from $230.80 to $560.50.
The tables below show the income levels that qualify for the different IRMAA amounts[0].
2022 Medicare Part B IRMAA
Individual tax return (2020 income)
Joint tax return (2020 income)
Married & separate tax return (2020 income)
Monthly Medicare Part B premium
Above $91,000 up to $114,000.
Above $182,000 up to $228,000.
Above $114,000 up to $142,000.
Above $228,000 up to $284,000.
Above $142,000 up to $170,000.
Above $284,000 up to $340,000.
Above $170,000 and less than $500,000.
Above $340,000 and less than $750,000.
Above $91,000 and less than $409,000.
2023 Medicare Part B IRMAA
Individual tax return (2021 income)
Joint tax return (2021 income)
Married & separate tax return (2021 income)
Monthly Medicare Part B premium
Less than or equal to $97,000.
Less than or equal to $194,000.
Less than or equal to $97,000.
Greater than $97,000 and less than or equal to $123,000.
Greater than $194,000 and less than or equal to $246,000.
Greater than $123,000 and less than or equal to $153,000.
Greater than $246,000 and less than or equal to $306,000.
Greater than $153,000 and less than or equal to $183,000.
Greater than $306,000 and less than or equal to $366,000.
Greater than $183,000 and less than $500,000.
Greater than $366,000 and less than $750,000.
Greater than $97,000 and less than $403,000.
Greater than or equal to $500,000.
Greater than or equal to $750,000.
Greater than or equal to $403,000.
2023 Medicare Part B IRMAA for immunosuppressive drug coverage only
Starting in 2023, Medicare enrollees who are 36 months post-kidney transplant can choose to get Part B coverage of immunosuppressive drugs by paying a monthly premium of $97.10. These enrollees can no longer get full Medicare coverage.
There's also an IRMAA amount for enrollees opting in to immunosuppressive drug coverage only:
Individual tax return (2021 income)
Joint tax return (2021 income)
Married & separate tax return (2021 income)
Monthly Medicare Part B premium
Less than or equal to $97,000.
Less than or equal to $194,000.
Less than or equal to $97,000.
Greater than $97,000 and less than or equal to $123,000.
Greater than $194,000 and less than or equal to $246,000.
Greater than $123,000 and less than or equal to $153,000.
Greater than $246,000 and less than or equal to $306,000.
Greater than $153,000 and less than or equal to $183,000.
Greater than $306,000 and less than or equal to $366,000.
Greater than $183,000 and less than $500,000.
Greater than $366,000 and less than $750,000.
Greater than $97,000 and less than $403,000.
Greater than or equal to $500,000.
Greater than or equal to $750,000.
Greater than or equal to $403,000.
Part B premiums with Medicare Advantage
Many people who sign up for Medicare choose a Medicare Advantage plan, also known as Medicare Part C. Medicare Advantage plans are sold by private insurance companies, and they must have at least the same coverage as Original Medicare (Part A and Part B). Often these policies include Medicare Part D prescription drug coverage and extra benefits not covered by Original Medicare, which may include some coverage for dental, vision, wellness and some home-care benefits.
You’re still responsible for your Medicare Part B premium even if you choose a Medicare Advantage plan[0]. However, some Medicare Advantage plans will pay for some or all of your Part B premiums.
To see whether a plan will pay for some or all of your Part B premium, look for Medicare Advantage plans with “Part B premium reduction” or “Giveback” benefits.
Medicare Part B deductibles and coinsurance
Medicare Part B comes with an annual deductible: $233 in 2022 ($226 in 2023)[0].
After you meet the deductible for the year, you typically pay 20% of the Medicare-approved amount for doctor services and other Medicare benefits. Medicare Part B pays the other 80%. This assumes your doctor or other provider accepts Medicare assignment. In other words, your provider will accept the amount Medicare agrees to pay for the treatment or service. Some providers who charge more than the Medicare-assigned amount may bill patients for the difference. Always check with a new physician or other health care provider that they accept the amount Medicare pays.
Many Original Medicare enrollees purchase Medicare Supplement Insurance, also called Medigap, to help pay the out-of-pocket costs associated with Medicare Part B.
The Medicare Part B penalty
It’s extremely important to sign up for Medicare Part B on time. If you decide not to sign up for Part B at age 65 when you become eligible and later change your mind, you’ll pay an extra 10% above the standard premium cost for every 12-month period you delayed[0]. What’s more, you’ll pay extra for the entire time you're covered by Medicare. That extra premium can add up to a significant amount over the course of your retirement.
Read more about the different parts of Medicare and what they cover.
If you have additional questions about Medicare, visit Medicare.gov or call 800-MEDICARE (800-633-4227, TTY 877-486-2048).
Frequently asked questions
When should you enroll in Medicare Part B?
If you’re already receiving Social Security or Railroad Retirement Board benefits, you’ll automatically start receiving Original Medicare, Part A and Part B, the month you turn 65.
Everyone else must choose among these enrollment period options:
Initial enrollment period: This is the seven-month period starting three months before the month you turn 65, including your birthday month and ending three months after your birthday month. So if you turn 65 in July, you’ll have from April 1 to Oct. 31 to enroll.
Special enrollment period: This is when you’re allowed to join Medicare or make changes to your coverage based on specific life events, such as leaving a job or moving out of your plan’s coverage area.
General enrollment period: This runs from Jan. 1 through March 31 every year and is the time when people who are already receiving Medicare benefits can make limited changes to their coverage. It’s also when people who miss the deadline for initial enrollment can sign up.
Note: You still need to sign up for Medicare Part B if you’re receiving health care continuation coverage under COBRA. Otherwise, you’ll pay the Part B penalty. COBRA beneficiaries aren't eligible for the special enrollment period. In other words, COBRA isn't the same as if you were covered under a large employer health plan.
Can I keep my doctor on Medicare?
If you have health care coverage through Medicare Part B (medical insurance), you can see any health care provider who accepts Medicare and who is accepting new Medicare patients. You’ll want to ask your doctor if they can take you as a new Medicare patient.
That said, not all providers accept Medicare as full payment. Medicare classifies health care providers three ways:
Participating: They accept Medicare and Medicare approved payment for services.
Nonparticipating: They accept Medicare but may charge more than Medicare’s approved payment for services.
Opt-out: They don’t accept Medicare at all, and patients are responsible for all costs for care, except for emergency care or urgently needed care.
How does Medicare Part B work with employer insurance?
You can choose to have both Medicare Part B and employer insurance, or you can choose to delay enrolling in Part B while you’re covered by the employer plan.
If you choose not to sign up for Medicare Part B right away and you’re covered by employer-sponsored insurance (yours or your spouse’s) from a company with 20 or more employees, you won’t need to pay the Part B late enrollment penalty. In those cases, unless you’re already receiving Social Security or Railroad Retirement Board benefits, you don’t have to do anything when you turn 65. (If you’re receiving Social Security or those benefits, and you want to delay Medicare Part B, follow the instructions that come with the Medicare card you’ll receive near your 65th birthday or call Social Security at 800-772-1213.)
If you decide to stick with employer-sponsored coverage without signing up for Medicare Part B, make sure you know when your coverage will end. You’ll need to take action when your employer-sponsored insurance ends. You have eight months to sign up for Part B before incurring the penalty.
If you sign up for Medicare Part B and keep your employer insurance, both of them can pay for your covered medical bills. Which coverage applies first depends on your plan and your employer, so check with your plan for information on how it coordinates with Medicare.