Medicare Part B

Coverage, costs, enrollment, and late-enrollment penalties explained.

Medicare Part B is the medical-insurance portion of Original Medicare. It covers doctor and specialist services, outpatient care, preventive services, durable medical equipment and many other medically necessary services.

Unlike premium-free Part A, Part B ordinarily requires a monthly premium. In 2026, most beneficiaries pay $202.90 per month and have a $283 annual deductible.

Understanding when to enroll is just as important as understanding the coverage. Delaying Part B without the correct employment-based insurance can cause coverage gaps and a permanent late-enrollment penalty.

What Does Medicare Part B Cover?

Medicare Part B primarily covers medically necessary services used to diagnose or treat a medical condition and preventive services intended to help detect or prevent illness.

Covered services may include:

  • Doctors and specialists
  • Outpatient hospital care
  • Emergency-room services
  • Observation stays
  • Outpatient surgery
  • Diagnostic tests and imaging
  • Clinical laboratory tests
  • Preventive screenings
  • Mental-health and substance-use treatment
  • Physical and occupational therapy
  • Ambulance transportation
  • Durable medical equipment
  • Certain home health services
  • Limited medications administered in a medical setting

Coverage depends on whether the service is medically necessary, whether the provider is properly enrolled and whether applicable coverage requirements are satisfied.

Doctor and Specialist Services

Part B covers medically necessary services provided by doctors and other qualified healthcare professionals.

This can include:

  • Primary-care appointments
  • Specialist consultations
  • Surgeon services
  • Anesthesiology
  • Second surgical opinions
  • Outpatient treatment
  • Certain telehealth services
  • Physician services received during an inpatient hospital stay

During an inpatient hospital stay, Part A generally covers the hospital facility. Part B ordinarily covers the doctors, surgeons, anesthesiologists and other medical professionals treating you.

Outpatient and Observation Care

Part B generally covers services received without formal inpatient admission, including:

  • Emergency-room treatment
  • Observation services
  • Outpatient surgery
  • Outpatient hospital procedures
  • Diagnostic imaging
  • Outpatient rehabilitation
  • Hospital-clinic services

Spending a night in the hospital does not automatically make you an inpatient. You can remain under observation even if you occupy a hospital bed overnight.

Observation status can affect which deductible applies, how much you owe and whether the stay satisfies the inpatient requirement for subsequent skilled-nursing facility coverage.

Preventive Services

Part B covers numerous preventive and screening services.

Examples include:

  • A one-time “Welcome to Medicare” preventive visit
  • Yearly wellness visits
  • Cardiovascular screenings
  • Cancer screenings
  • Diabetes screenings
  • Bone-mass measurements
  • Depression screenings
  • Certain vaccines
  • Tobacco-use counseling
  • Obesity counseling
  • Medical nutrition therapy for eligible patients

The “Welcome to Medicare” visit must occur within the first 12 months after your coverage begins. It is a preventive visit, not a comprehensive physical examination.

The yearly wellness visit is also not a routine physical. It focuses on developing or updating a personalized prevention plan.

Many preventive services have no deductible or coinsurance when you meet the eligibility requirements and receive the service from a provider who accepts assignment. Additional diagnostic or treatment services performed during the same appointment may create a separate charge.

Durable Medical Equipment

Part B may cover medically necessary durable medical equipment prescribed for use in your home.

Examples include:

  • Wheelchairs
  • Walkers
  • Hospital beds
  • Oxygen equipment
  • Continuous positive airway pressure equipment
  • Blood-sugar monitors
  • Certain prosthetic and orthotic devices
  • Patient lifts

The prescribing practitioner and equipment supplier generally must be properly enrolled. After satisfying the deductible, you ordinarily pay 20 percent of the approved amount.

Mental-Health and Therapy Services

Covered outpatient mental-health services may include:

  • Individual and group psychotherapy
  • Psychiatric evaluations
  • Medication-management appointments
  • Certain substance-use disorder treatments
  • Partial hospitalization
  • Intensive outpatient services
  • Depression screenings

Part B may also cover medically necessary physical therapy, occupational therapy and speech-language pathology services.

There is no fixed annual dollar limit for medically necessary outpatient therapy. Documentation and additional review requirements can apply as the cost of treatment increases.

Ambulance Services

Part B may cover ambulance transportation when another form of transportation could endanger your health.

Coverage may include:

  • Emergency ground ambulance transportation
  • Certain nonemergency ambulance transportation
  • Air ambulance transportation when rapid transport is medically necessary and ground transportation cannot reasonably provide it

Ambulance coverage is based on medical necessity. Transportation provided mainly for convenience is not covered.

Limited Outpatient Prescription Drugs

Part B covers a limited group of medications under specific circumstances.

These may include:

  • Drugs administered in a doctor’s office
  • Certain injectable or infused medications
  • Some medications used with durable medical equipment
  • Certain cancer medications
  • Immunosuppressive medications in qualifying situations
  • Flu, pneumococcal, COVID-19 and certain hepatitis B vaccines

Most medications you obtain from a pharmacy and take yourself are covered through Part D rather than Part B.

What Are the 2026 Medicare Part B Costs?

The principal 2026 costs are:

  • Standard monthly premium: $202.90
  • Annual deductible: $283
  • General coinsurance: Usually 20 percent of the approved amount after the deductible

These amounts can change each year.

The Monthly Premium

Most beneficiaries pay the standard $202.90 monthly premium in 2026.

You pay the premium every month, even if you do not receive any covered medical services during that month.

The premium is usually deducted automatically from:

  • Social Security benefits
  • Railroad Retirement Board benefits
  • Certain federal retirement benefits

People who do not receive one of these benefit payments are ordinarily billed directly.

Higher-income beneficiaries may pay more because of IRMAA. A late-enrollment penalty can also increase the monthly amount.

The Annual Deductible

The 2026 annual deductible is $283.

Unlike the Part A hospital deductible, the Part B deductible generally applies once per calendar year rather than once per benefit period.

After you meet the deductible, the program ordinarily pays 80 percent of the approved amount for most covered services. You are responsible for the remaining 20 percent unless another policy pays it.

Some services, including many preventive services and covered clinical laboratory tests, may not require the deductible or 20-percent coinsurance.

Outpatient Hospital Charges

Outpatient hospital care can involve more than the standard 20-percent coinsurance.

You may owe:

  • Coinsurance for the doctor or healthcare professional
  • A separate hospital outpatient copayment
  • Charges for noncovered services
  • Costs for certain self-administered medications

An outpatient procedure performed at a hospital can sometimes cost more than the same service performed in a doctor’s office or independent facility.

Does Part B Have an Out-of-Pocket Maximum?

Original Medicare does not place an annual maximum on your Part A and Part B expenses.

Without supplemental coverage, your responsibility can include:

  • The annual deductible
  • Twenty-percent coinsurance
  • Outpatient hospital copayments
  • Durable medical equipment coinsurance
  • Therapy expenses
  • Legally permitted excess charges
  • Noncovered services

A Medicare Supplement can help pay many of these expenses. Medicare Advantage plans establish their own annual maximum for covered Part A and Part B services.

Why Do Some People Pay a Higher Premium?

IRMAA stands for Income-Related Monthly Adjustment Amount. It is an additional amount paid by beneficiaries whose modified adjusted gross income exceeds specified thresholds.

For 2026, Social Security generally uses income reported on your 2024 federal tax return.

For individual filers and married couples filing jointly, the 2026 monthly amounts are:

  • Income up to $109,000 individual or $218,000 joint: $202.90
  • Above $109,000 through $137,000 individual or above $218,000 through $274,000 joint: $284.10
  • Above $137,000 through $171,000 individual or above $274,000 through $342,000 joint: $405.80
  • Above $171,000 through $205,000 individual or above $342,000 through $410,000 joint: $527.50
  • Above $205,000 and below $500,000 individual or above $410,000 and below $750,000 joint: $649.20
  • $500,000 or more individual or $750,000 or more joint: $689.90

Different thresholds apply to certain married people who file separate returns.

If your income has fallen because of retirement, marriage, divorce, the death of a spouse, loss of income-producing property or another qualifying life-changing event, you may be able to request a new determination using Social Security Form SSA-44.

IRMAA is separate from the late-enrollment penalty. Someone can be subject to one, both or neither.

When Should You Enroll in Part B?

Your correct enrollment date depends on whether you are receiving Social Security, whether you are still working and what kind of health insurance you currently have.

Automatic Enrollment

If you are already receiving Social Security or Railroad Retirement Board benefits at least four months before turning 65, you will generally be enrolled automatically in Parts A and B.

Your card should arrive before coverage begins.

If you do not want Part B because you have qualifying employment-based insurance, follow the instructions included with the card. Do not decline it until you have confirmed how the employer plan coordinates with coverage at age 65.

Initial Enrollment Period

If you are not receiving Social Security benefits, you generally must enroll yourself.

Your Initial Enrollment Period ordinarily lasts seven months:

  • Three months before the month you turn 65
  • The month you turn 65
  • Three months after the month you turn 65

Applying before your birthday month can help prevent a delay in coverage.

People eligible because of disability, ALS or End-Stage Renal Disease may have different enrollment rules.

Can You Delay Part B While Still Working?

Many people can delay enrollment while covered by a group health plan based on their own or their spouse’s current employment.

The important phrase is current employment.

“Creditable coverage” is primarily a Part D prescription-drug term. Simply having health insurance does not automatically protect your right to delay Part B.

Consider:

  • Whether you or your spouse are actively employed
  • The number of employees working for the employer
  • Whether the group plan pays before or after Medicare
  • The cost of adding Part B
  • The employer-plan premium, deductible and network
  • Whether you are contributing to an HSA
  • When the employment or group coverage will end

For a person age 65 or older:

  • An employer plan from a company with 20 or more employees generally pays first.
  • Medicare generally pays first when the employer has fewer than 20 employees.

If Medicare should be primary and you delay Part B, the employer plan may calculate claims as though Medicare had paid first. That can leave a substantial unpaid balance.

Always confirm the coordination rules with the employer’s benefits administrator before delaying enrollment.

The Eight-Month Special Enrollment Period

When qualifying current-employment coverage ends, you generally receive an eight-month Special Enrollment Period.

The eight-month period begins when the employment ends or the group health coverage ends, whichever happens first.

You can also enroll while the current-employment coverage remains active.

Do not automatically wait until the end of the eight months. Coordinate the effective date so the employer plan and Part B coverage do not leave a gap.

COBRA and Retiree Coverage

COBRA and retiree insurance are not considered coverage based on current employment for this enrollment rule.

The eight-month period generally begins when the employment or active-employment coverage ends—not when COBRA ends.

Waiting until COBRA or retiree coverage expires can cause:

  • A late-enrollment penalty
  • A gap in medical coverage
  • Delayed access to a Medicare Supplement
  • The need to use the General Enrollment Period

Marketplace coverage, most individual insurance and VA healthcare also do not ordinarily protect the current-employment Special Enrollment Period.

TRICARE and CHAMPVA have separate coordination rules and generally require enrollment in Parts A and B once eligible, subject to specific exceptions.

Part B and HSA Contributions

You cannot make or receive HSA contributions for months in which you are enrolled in any part of Medicare.

Delaying Part B does not preserve HSA eligibility if you have already enrolled in premium-free Part A.

Because Part A can become retroactive when someone applies after age 65, coordinate HSA contributions carefully before applying for Social Security or Medicare benefits.

What Is the Part B Late-Enrollment Penalty?

The penalty generally adds 10 percent of the standard monthly premium for each full 12-month period you could have enrolled but did not.

In most cases, you pay the penalty for as long as you have Part B.

For example, someone who delayed enrollment for two full years without qualifying for a Special Enrollment Period would have a 20-percent penalty.

Using the 2026 standard premium:

  • Standard premium: $202.90
  • Twenty-percent penalty: $40.58
  • Total before rounding: $243.48
  • Monthly amount after Medicare’s rounding: $243.50

The dollar amount can change when the standard premium changes. IRMAA, if applicable, is added separately.

What Is the General Enrollment Period?

The General Enrollment Period runs from January 1 through March 31 each year.

It is available to people who missed their initial enrollment opportunity and do not qualify for a Special Enrollment Period.

Coverage ordinarily begins the first day of the month after you enroll.

A late-enrollment penalty may still apply. Although the newer coverage-start rules reduce the waiting time, missing the proper enrollment window can still create a costly gap.

Assignment and Excess Charges

A provider who accepts assignment agrees to accept the Medicare-approved amount as payment in full for a covered service.

You remain responsible for the applicable deductible and coinsurance, but the provider cannot add an excess charge.

A non-participating provider is enrolled but has not agreed to accept assignment on every claim. The provider may still accept assignment for an individual service.

When assignment is not accepted, federal law generally allows a non-participating provider to charge up to 15 percent above the approved amount. This is called the limiting charge.

An opt-out provider is different. An opt-out provider generally does not bill Medicare and may ask you to sign a private contract agreeing to pay the provider directly. A private-contract charge is not a Part B excess charge.

Pennsylvania prohibits healthcare practitioners from balance billing beneficiaries above the approved amount for covered services received in Pennsylvania. However, private contracts with opt-out providers and healthcare received in another state are separate situations.

What Does Part B Not Cover?

Part B generally does not cover:

  • Routine physical examinations
  • Most routine dental care
  • Dentures
  • Routine eye examinations for prescription glasses
  • Most eyeglasses and contact lenses
  • Hearing aids
  • Examinations for fitting hearing aids
  • Long-term custodial care
  • Most outpatient medications taken at home
  • Massage therapy
  • Most cosmetic surgery
  • Concierge or membership fees
  • Personal-comfort items
  • Most healthcare received outside the United States
  • Services that are not medically necessary
  • Nonemergency services from providers who have opted out

Specific exceptions exist. For example, coverage may be available for eyeglasses following cataract surgery and for certain dental services that are directly connected to covered medical treatment.

Part A vs Part B

Parts A and B together make up Original Medicare.

Part A primarily covers:

  • Inpatient hospital care
  • Limited skilled-nursing facility care
  • Hospice care
  • Certain home health services

Part B primarily covers:

  • Doctors and specialists
  • Outpatient care
  • Preventive services
  • Diagnostic testing
  • Therapy
  • Durable medical equipment
  • Ambulance services
  • Certain medications administered in a medical setting

A hospital visit can involve both. Part A may cover the inpatient facility while Part B covers the doctors treating you.

How Does Part B Work With a Medicare Supplement?

A Medicare Supplement works alongside Original Medicare.

To purchase a Medicare Supplement, you generally must be enrolled in both Parts A and B and continue paying the Part B premium.

Your six-month Medigap Open Enrollment Period generally begins on the first day of the month in which you are both:

  • Age 65 or older
  • Enrolled in Part B

During this period, insurance companies generally cannot use your health history to deny standardized Medigap coverage or increase the premium because of medical conditions.

After the annual deductible:

  • Plan G generally covers the remaining Part B coinsurance.
  • Plan N generally covers the coinsurance but may leave specified office and emergency-room copays.
  • Plan N does not cover legally permitted excess charges.
  • Plan G does cover qualifying excess charges.
  • Neither Plan G nor Plan N pays the annual Part B deductible.

Older Plan F and Plan C policies may cover the deductible, but those plans are not available to people who first became eligible for Medicare on or after January 1, 2020.

How Does Part B Work With Medicare Advantage?

You must generally have Parts A and B to enroll in Medicare Advantage, and you must continue paying the monthly Part B premium.

You remain enrolled in Medicare, but the private Medicare Advantage company administers your Part A and Part B benefits.

The plan may establish its own:

  • Copayments
  • Coinsurance
  • Deductibles
  • Provider network
  • Referral rules
  • Prior-authorization requirements
  • Service area
  • Annual out-of-pocket maximum

A Medicare Advantage plan’s medical costs do not necessarily follow Original Medicare’s $283 deductible and 20-percent coinsurance structure.

The Bottom Line

Medicare Part B covers doctor services, outpatient treatment, preventive care, diagnostic testing, medical equipment and many other medically necessary services.

In 2026, the standard monthly premium is $202.90 and the annual deductible is $283. After the deductible, beneficiaries ordinarily pay 20 percent of the approved amount for most covered services.

The enrollment decision becomes more complicated when you continue working. Coverage based on current employment may allow you to delay, but COBRA, retiree insurance and other nonemployment coverage generally do not provide the same protection.

Confirm the employer’s size, which coverage pays first and when your Special Enrollment Period begins before delaying enrollment.

Frequently Asked Questions

What does Medicare Part B cover?

Medicare Part B covers doctors, specialists, outpatient treatment, preventive services, durable medical equipment, diagnostic testing, ambulance services, therapy and certain medications.

How much is the Part B premium in 2026?

The standard 2026 monthly premium is $202.90. Higher-income beneficiaries and people with late-enrollment penalties may pay more.

What is the 2026 annual deductible?

The annual deductible is $283. It generally applies once per calendar year.

Does Part B pay 100 percent after the deductible?

No. It ordinarily pays 80 percent of the approved amount for most covered services. You are responsible for the remaining 20 percent unless supplemental coverage pays it.

Can I delay enrollment if I am still working?

Possibly. You may be able to delay if you have group coverage based on your or your spouse’s current employment. The employer’s size and which insurance pays first are important.

Does COBRA allow me to delay enrollment?

Generally, no. COBRA is not coverage based on current employment. Your eight-month Special Enrollment Period ordinarily begins when the employment or active-employment coverage ends, not when COBRA ends.

How long does the late-enrollment penalty last?

In most cases, the penalty remains for as long as you have Part B.

Does Part B cover prescription drugs?

It covers a limited number of medications, usually drugs administered in a doctor’s office or outpatient medical setting. Most prescriptions taken at home require Part D or other drug coverage.

Does Part B cover routine physical examinations?

No. It covers the “Welcome to Medicare” preventive visit and yearly wellness visits, but neither is a comprehensive routine physical.

Can I use Part B anywhere in the United States?

With Original Medicare, you can generally receive covered services from participating providers throughout the United States. Medicare Advantage plans may have network and service-area restrictions.

Related Medicare Topics

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