Medicare is a federal health insurance program for those that are 65 and older and other specific groups. It consists of several parts, one of which is Part B.

Medicare Part B is the part of Medicare that provides medical insurance. You can use it to cover various outpatient services. Continue reading to learn more details about Part B, including what it covers, how much it costs, and when to enroll.

Along with Part A, Part B makes up what’s called original Medicare. It’s estimated that at the end of 2016, 67 percent of people using Medicare were enrolled in original Medicare.

Part B covers a wide variety of medically necessary outpatient services. A service is determined to be medically necessary if it’s needed to effectively diagnose or treat a health condition.

Some examples of services covered by Part B are:

Part B also covers some preventative services as well. Examples include:

There are some services that aren’t covered by Part B. If you need these services, you’ll need to pay for them out of pocket. Some examples of these include:

If you’d like prescription drug coverage, you can purchase a Medicare Part D plan. Part D plans are offered by private insurance companies and include most prescription drugs.

Additionally, Medicare Part C (Medicare Advantage) plans include all services covered under original Medicare as well as some additional services like dental, vision, and even fitness programs. If you know you’ll need these services frequently, consider a Part C plan.

Generally speaking, these groups are eligible for Part B:

An individual must qualify for premium-free Part A to also be eligible for Part B when they’re first able to enroll in Medicare. Because people often pay Medicare taxes while they’re working, most people are eligible for premium-free Part A and can also enroll in Part B when they’re first eligible for Medicare.

If you need to buy Part A, you can still enroll in Part B. However, you must meet the following requirements:

  • be age 65 or older
  • be a resident of the United States, either a citizen or a legal permanent resident for at least 5 continuous years

Now let’s look at each of the costs associated with Part B in 2022.

Monthly premium

Your monthly premium is what you pay each month for Part B coverage. For 2022, the standard Part B monthly premium is $170.10.

People with higher yearly incomes may have to pay higher monthly premiums. Your yearly income is determined based on your tax return from two years ago. So for 2022, this would be your 2020 tax return.

There’s also a late enrollment penalty that can affect your Part B monthly premium. You’ll pay this if you didn’t enroll in Part B when you were first eligible.

When you need to pay the late enrollment penalty, your monthly premium can increase up to 10 percent of the standard premium for each 12-month period that you were eligible for Part B but didn’t enroll. You’ll pay this as long as you’re enrolled in Part B.


A deductible is what you need to pay out-of-pocket before Part B starts to cover services. For 2022, the deductible for Part B is $233.


Coinsurance is the percentage of the cost of a service that you pay out of pocket after meeting your deductible. This is typically 20 percent for Part B.


A copay is a set amount that you pay for a service. Copays aren’t typically associated with Part B. However, there are some cases where you may need to pay one. An example is if you use hospital outpatient services.

Out-of-pocket maximums

An out-of-pocket maximum is a limit on how much you’ll have to pay out of pocket for covered services during the year. Original Medicare doesn’t have an out-of-pocket maximum.

Some people are automatically enrolled in original Medicare while others will need to sign up. Let’s explore this further.

Who is automatically enrolled?

Groups that are automatically enrolled in original Medicare are:

  • those who are turning age 65 and already getting retirement benefits from the Social Security Administration (SSA) or the Railroad Retirement Board (RRB)
  • people under age 65 with a disability who have been receiving disability benefits from the SSA or RRB for 24 months
  • individuals with amyotrophic lateral sclerosis (ALS) who are getting disability benefits

It’s important to note that even though you’ll be automatically enrolled, Part B is voluntary. You can choose to delay Part B if you wish. One situation where this may occur is if you’re already covered by another plan through work or a spouse.

Who must sign up?

Remember that not everyone who is eligible for original Medicare will be automatically enrolled. Some will need to sign up through the SSA office:

  • Those who are turning 65 years old and are not currently getting retirement benefits from the SSA or RRB can sign up beginning 3 months before they turn age 65.
  • People with ESRD can sign up at any time — when your coverage will begin may vary.

When can I apply?

  • Initial enrollment period. This is a 7-month window around your 65th birthday when you can sign up for Medicare. It begins 3 months before your birth month, includes the month of your birthday, and extends 3 months after your birthday. During this time, you can enroll for all parts of Medicare without a penalty.
  • Open enrollment period (October 15–December 7). During this time, you can switch from original Medicare (parts A and B) to Part C (Medicare Advantage), or from Part C back to original Medicare. You can also switch Part C plans or add, remove, or change a Part D plan.
  • General enrollment period (January 1–March 31). You can enroll in Medicare during this time frame if you didn’t enroll during your initial enrollment period.
    • Special enrollment period. If you delayed Medicare enrollment for an approved reason, you can later enroll during a special enrollment period. You have 8 months from the end of your coverage or the end of your employment to sign up without penalty.
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Medicare Part B is the part of Medicare that covers medically necessary outpatient services. It also covers some preventative services. It’s part of original Medicare

People who are age 65 or older, have a disability, or ESRD are eligible for Part B. The costs of part B include monthly premiums, a deductible, and coinsurance or copay. Some services aren’t covered by Part B and will need to be paid out of pocket.

Many people are automatically enrolled in original Medicare. Some will have to sign up through the SSA. For these individuals, it’s important to pay attention to enrollment deadlines.

Medicare plan options and costs are subject to change each year.