What’s the Difference Between Medicare Part A and Part B?

The 30-second answer (because life is short and waiting rooms are long)

• Medicare Part A (Hospital Insurance): Mainly covers inpatient carehospital stays, skilled nursing facility care after a qualifying hospital stay, hospice, and some home health care.
• Medicare Part B (Medical Insurance): Mainly covers outpatient caredoctor visits, preventive services, tests, outpatient procedures, ambulance services, durable medical equipment (DME), and more.
• Big cost difference: Part A is premium-free for most people who have enough work history, while Part B usually has a monthly premium.
• Big billing difference: Part A has a deductible tied to a benefit period; Part B has an annual deductible and often 20% coinsurance for covered services.

Part A vs. Part B at a glance

Medicare Part A: what it covers (and why it’s called “hospital insurance”)

Think of Part A as “admitted” coverage

Medicare Part A mainly helps pay for care when you’re officially admitted as an inpatient.
That one wordinpatientmatters a lot. It can be the difference between Part A paying like it’s got
your back, versus you discovering you were technically “under observation” (which is usually billed under Part B).

What Part A generally covers

• Inpatient hospital stays (including critical access hospitals)
• Skilled nursing facility (SNF) care after a qualifying inpatient hospital stay (this is not long-term custodial nursing home care)
• Hospice care for people who meet eligibility requirements
• Some home health care (when you qualify)

What Part A usually does not cover (common surprises)

• Long-term custodial care in a nursing home (help with bathing, dressing, eating, etc.)
• Most routine dental, vision, and hearing services
• Private-duty nursing (in most situations)
• Many non-medically necessary add-ons (yes, even if they come with a comforting pillow)

Part A costs: the benefit period is the plot twist

Part A costs aren’t primarily “per year.” They’re tied to something called a benefit period.
A benefit period starts the day you’re admitted as an inpatient in a hospital (or SNF) and ends after you’ve gone
60 days in a row without inpatient hospital or skilled SNF care. If you start a new benefit period,
you can owe the deductible againyes, even in the same year.

For example, if you’re hospitalized, recover at home for 70 days, and then get hospitalized again, that can be a
new benefit period with a fresh deductible. Not funbut very important to understand.

Part A cost example (2026 numbers, because specifics help)

In 2026, the Part A inpatient hospital deductible is $1,736 per benefit period.
After you meet that deductible, hospital days 1–60 are typically $0 coinsurance. Longer stays can trigger daily
coinsurance amounts (for example, days 61–90 and beyond). Skilled nursing facility coinsurance can also apply for
days 21–100 in a benefit period.

Translation: Part A can be generous early in a stay, but it’s not an unlimited “all you can eat” buffet of hospital coverage.

Part A premium: “free for most people” doesn’t mean “free for everyone”

Many people pay $0 for Part A because they (or a spouse) have enough work history paying Medicare taxes.
If you don’t qualify for premium-free Part A, you may be able to buy Part A and pay a monthly premium.

Medicare Part B: what it covers (and why it’s the “everyday healthcare” side)

Think of Part B as “boots on the ground” healthcare

Part B is where most day-to-day healthcare lives: primary care visits, specialist appointments, outpatient surgeries,
imaging, lab work, and preventive services. If Part A is “the building” (hospital/SNF), Part B is “the services”
(doctors, tests, treatments) that happen in and out of that building.

What Part B generally covers

• Doctor and other health care provider services
• Outpatient care (including outpatient surgery and hospital outpatient services)
• Preventive services (screenings, vaccines, annual wellness-type visits, etc.)
• Ambulance services in covered situations
• Durable medical equipment (DME) like walkers, wheelchairs, oxygen equipment (when medically necessary)
• Mental health and substance use disorder services (in many outpatient settings)
• Limited outpatient prescription drugs (certain situationsmost retail prescriptions are typically Part D territory)

Part B costs: annual deductible + coinsurance (often 20%)

Part B generally has:
(1) a monthly premium,
(2) a yearly deductible, and
(3) coinsurance for many services after the deductible is met.

In 2026, the standard Part B premium is $202.90/month, and the
Part B deductible is $283/year. After you meet the deductible, you typically pay
20% coinsurance of the Medicare-approved amount for many covered services.

Part B premium isn’t one-size-fits-all: meet IRMAA

If your income is above certain thresholds, you may pay more than the standard Part B premium. This is called the
Income-Related Monthly Adjustment Amount (IRMAA), and it’s generally based on your
modified adjusted gross income (MAGI) from two years ago. So yesyour 2024 income can influence your 2026 Part B premium.

Practical tip: if you had a major life change (like retirement), you may be able to request a redetermination so your premium reflects your current situation.

The sneaky part: inpatient vs. outpatient (and why “observation status” matters)

Here’s a classic Medicare “gotcha” that catches smart people all the time:
you can spend the night in a hospital and still be considered outpatient.
Hospitals may place you under observation while deciding whether to admit you as an inpatient.

Why you should care:

• If you’re inpatient, Part A is typically the main payer for the facility stay.
• If you’re outpatient/observation, Part B usually applies, which can change your cost-sharingand can affect eligibility for certain follow-up care rules (like SNF coverage requirements).

The takeaway: don’t be afraid to ask, “Am I admitted as an inpatient?” It’s not rude. It’s financial self-defense.

Enrollment timing: when you sign up affects what you pay

The Initial Enrollment Period (IEP): your first big window

When you first become eligible for Medicare (often around age 65, or earlier in some disability situations),
you typically get an Initial Enrollment Period. Missing it can mean delayed coverage and potential penalties,
especially for Part B.

Special Enrollment Periods (SEP): the “I’m still working” exception

If you (or your spouse) are still working and you’re covered by an employer plan, you might be able to delay Part B
and enroll later without penaltyif you qualify for a Special Enrollment Period. This is one of those “details matter”
situations where the size and type of employer coverage can change the right answer.

General Enrollment Period (GEP): the “I missed it” backup plan

If you miss your chance to enroll and don’t qualify for a Special Enrollment Period, you may have to use the
General Enrollment Period (which happens early each year) and your coverage may not start immediately.

Late enrollment penalties: the price of procrastination (Part B is the strict parent)

Part B has a well-known late enrollment penalty: generally, your premium can increase by
10% for each full 12-month period you could have had Part B but didn’t sign upand you may pay that higher premium
for as long as you have Part B.

There can also be penalties for late enrollment in premium Part A (for people who must pay for Part A), but the Part B penalty is the one that tends to surprise people the mostbecause it can stick around.

How Part A and Part B work together in real life

In the real world, Part A and Part B often tag-team the same medical event. Here’s a simple example:

Example: knee replacement surgery

• Part B may cover: surgeon fees, anesthesia, outpatient pre-op visits, imaging, and follow-up appointments.
• Part A may cover: your inpatient hospital stay (if you’re admitted), plus certain inpatient facility costs.
• Part B may also cover: durable medical equipment like a walker, and outpatient physical therapy afterward.

The point: Part A vs. Part B is less “either/or” and more “which piece pays for which slice.”

What Original Medicare (A + B) still doesn’t cover well

Original Medicare is solid, but it’s not a magical healthcare blank check. Common gaps include:

• Most routine dental, vision, and hearing care
• Most prescription drugs you pick up at a pharmacy (often covered through Part D instead)
• A built-in annual out-of-pocket maximum (Original Medicare doesn’t cap your cost-sharing the way many private plans do)

Because of these gaps, many people add coverage. Which brings us to the Medicare “extended universe.”

Common add-ons (so you don’t confuse “Medicare” with “all of Medicare”)

Part D (Prescription Drug Coverage)

Part D is optional drug coverage offered through private plans approved by Medicare. If you stick with Original Medicare,
you typically add Part D separately for retail prescription coverage.

Medigap (Medicare Supplement Insurance)

Medigap policies (sold by private insurers) can help pay some of the costs Original Medicare doesn’tlike deductibles,
copayments, and coinsurance. If you like the flexibility of Original Medicare but hate surprise bills, Medigap is the
“seatbelt” many people consider.

Part C (Medicare Advantage)

Medicare Advantage plans are offered by private companies and bundle your Part A and Part B benefits (and often Part D).
Many include extra benefits (like dental/vision/hearing), and they typically have an annual out-of-pocket limit.
But they often use provider networks and may require referrals or prior authorization for some services.

Frequently asked questions (asked by real humans, not robots)

Do I “need” Part B if I have Part A?

It depends, but many people do enroll in Part B because it covers the majority of routine medical services
(doctor visits, outpatient care, preventive services, and medical equipment). If you delay Part B, you’ll want to be
very sure you have other coverage that keeps you protected and avoids penalties.

Is Part A always free?

Part A is premium-free for many people, but not everyone. If you don’t have enough work history (or a spouse’s work history)
to qualify, you may pay a monthly premium to buy Part A.

Why do I keep hearing “20% coinsurance” with Part B?

Because after you meet the Part B deductible, many covered services generally require you to pay 20% of the Medicare-approved amount.
That can be manageable for routine visitsand a bigger deal for expensive outpatient treatments.

Does Part A cover nursing homes?

Part A can cover limited skilled nursing facility care under specific conditions (usually after a qualifying hospital stay),
but it generally doesn’t cover long-term custodial nursing home care.

Decision guide: Which costs should you plan for?

If you want a practical mental model, try this:

• Plan A costs for “big events”: hospital stays, rehab stays, hospice-related care.
• Plan B costs for “ongoing life”: monthly premiums, doctor visits, tests, preventive care, outpatient treatments.
• Plan for gaps: prescriptions (Part D), cost-sharing (Medigap), or bundled coverage (Medicare Advantage).

And if you’re still unsure, talk with a trusted benefits counselor (like a State Health Insurance Assistance Program),
especially if you’re working past 65, have retiree coverage, or have a complex medication list.

Wrapping it up (without billing you 20% coinsurance for reading)

The difference between Medicare Part A and Part B is simple at the headline level:
Part A helps cover inpatient/hospital-related care and Part B helps cover outpatient/medical services.
The detailsbenefit periods, deductibles, premiums, coinsurance, enrollment timingare where people either feel confident
or feel like they’re trying to assemble IKEA furniture without the instructions.

Get the basics right, enroll on time, and choose add-on coverage that matches your health needs and budget.
Your future self will thank youpossibly from the comfort of a doctor’s office that you can afford to visit.

Experiences and real-world scenarios (common stories that make the difference “click”)

You don’t truly understand Part A vs. Part B until you see how it plays out in everyday decisions. Below are
composite scenarios based on common situations people run intonames changed, drama preserved,
and paperwork implied.

1) “I stayed overnight, so Part A covered it… right?”

One of the most common “Medicare moments” is the overnight hospital stay that isn’t technically inpatient.
In this scenario, someone goes to the ER, gets admitted to a bed, receives tests, and sleeps thereonly to learn later
they were under observation. That can shift billing toward Part B instead of Part A.
The lesson people take away is wonderfully simple: ask the hospital staff, “Am I inpatient or outpatient?”
It feels awkward for five seconds and can save you from weeks of confusion later.

2) Surgery: Part A and Part B both show up with clipboards

After a joint replacement, many people expect “the hospital bill” to be one thing. In reality, it can be multiple
layers: facility charges (often Part A if inpatient), professional fees (often Part B), anesthesia (Part B),
imaging (Part B), and then physical therapy after discharge (Part B). This is where people start appreciating add-on
coverage like Medigap, because that 20% Part B coinsurance can feel small until you multiply it by “outpatient everything.”

3) “I’m healthyI’ll skip Part B and save money” (the future-you plot twist)

Some people delay Part B because they rarely see a doctor and don’t want another monthly bill. Then a health issue pops up:
new medications, specialist visits, imaging, outpatient proceduresservices that are typically Part B territory.
The experience that sticks is realizing that Part B is less about “how sick am I today?” and more about “how quickly could
I need outpatient care tomorrow?” If you can delay Part B safely (with qualifying employer coverage), great. If not,
the late enrollment penalty can turn “saving money” into “paying extra forever.”

4) Rehab after hospitalization: SNF coverage is not the same as a nursing home

After a hospital stay, some people need short-term rehab in a skilled nursing facility. This is where Part A can help,
but only under specific rules and time limits. The lived experience here is emotional: families hear “nursing facility”
and assume long-term care is covered. Then they learn Medicare is focused on skilled care and recovery,
not indefinite custodial support. The most useful takeaway is planning earlyasking discharge planners what qualifies,
what the expected length is, and what costs could look like if recovery takes longer than expected.

5) The IRMAA surprise: “Why is my Part B premium higher than my friend’s?”

Another common story: two retirees compare Part B premiums at brunch. One pays the standard amount; the other pays more.
Cue confusion, followed by the discovery of IRMAA (income-related premium adjustments) based on income from two years ago.
People often feel blindsided if they had a one-time income spikeselling property, taking large IRA withdrawals,
or a big capital gain. The “experience lesson” is to coordinate retirement income decisions with Medicare timing,
and to know that a major life change may allow you to request a premium redetermination.