Medicare Part B: Coverage, Cost, and Eligibility

Medicare Part B is one of the two main components of Original Medicare, working alongside Part A.

While Part A focuses on hospital-based care, Medicare Part B is your medical insurance and covers many of the same things that a standard health insurance policy covers.

It pays for two main types of services:

• Medically Necessary Outpatient Services: Part B covers many supplies and services designed to diagnose or treat various medical conditions. To be covered by Medicare, medically necessary services and supplies must meet the accepted standards of medical practice.
• Preventive Services: Preventing illness or detecting and treating it quickly is typically the best treatment option. Medicare Part B covers preventive care for this purpose.

Whether you’re preparing to enroll in Medicare or reviewing your current benefits, understanding what Part B includes and how it works is an essential part of healthcare planning.

Let’s start by looking at exactly what Medicare Part B covers.

What Does Medicare Part B Cover?

Medicare Part B provides coverage for medically necessary services and preventive care. These services help diagnose or treat medical conditions and prevent health problems from developing or worsening.

Examples of what preventative services your Part B insurance will pay for:

• Covid-19 vaccines
• Colonoscopies
• Mammograms
• Hepatitis B, flu, and pneumococcal shots
• Diabetes, cancer, and cardiovascular screenings
• Glaucoma tests
• Bone density measurements
• Alcohol misuse and depression screenings

Examples of what outpatient costs your Medicare Part B medical insurance will pay for:

• Limited outpatient prescription drugs (in most cases, though, this should be covered by a Medicare Part D prescription drug plan)
• Seeing another doctor to get a second opinion before undergoing surgery
• Inpatient, outpatient, and partial hospitalization for mental health purposes
• Durable medical equipment
• Clinical research
• Ambulance services
• Doctor visits
• Physical therapy

What Is Not Covered by Medicare Part B?

Medicare Part B covers many outpatient and preventive services, but it doesn’t cover some key types of care and services. Knowing these gaps is important so you can plan for extra insurance or out-of-pocket costs.

Here’s a quick look at what Medicare Part B doesn’t cover:

Prescription drugs: Most medications taken at home are not covered. You’ll need a Medicare Part D plan or a Medicare Advantage plan with drug coverage. Part B only covers limited outpatient drugs, like certain injections administered in a clinical setting. Dental care: Routine services such as cleanings, fillings, crowns, dentures, and extractions are excluded. Separate dental insurance or a Medicare Advantage plan may offer these benefits. Vision care: Regular eye exams, eyeglasses, and contact lenses are not covered unless related to cataract surgery. However, eye conditions like glaucoma or diabetic retinopathy may be covered under certain criteria. Hearing services: Routine hearing exams and hearing aids are not covered under Part B. They are often offered through Medicare Advantage plans or separate hearing insurance. Long-term care: Custodial care in nursing homes or assisted living facilities is not covered. Part B only covers medically necessary skilled nursing care on a short-term basis after hospitalization. Foreign medical care: Treatment received outside the United States is generally not covered. Limited exceptions apply in very specific emergencies. Cosmetic surgery: Procedures performed for aesthetic purposes are not covered. Reconstructive surgery may be covered if it is medically necessary, such as after an injury or mastectomy. Alternative therapies: Part B does not cover services like massage therapy, acupuncture (except for chronic low back pain), and naturopathic treatments. Routine foot care: Services like nail trimming, callus removal, and corn treatment are excluded unless medically necessary due to conditions like diabetes. Personal comfort items: Items such as hospital room televisions, telephones, toiletries, or private-duty nursing are not considered medically necessary or covered.

Medicare Part B Costs in 2025

Medicare Part B requires monthly premiums, a deductible, and cost-sharing for services. The standard monthly premium in 2025 is $185. Based on their tax returns from two years prior, people with higher incomes may pay more.

This additional charge is known as the Income-Related Monthly Adjustment Amount, or IRMAA.

Here is a breakdown highlighting how your income level impacts IRMAA and total premiums:

Single Filers:

• Income of $106,000 or less: No IRMAA applies, and the standard premium is $185.
• Income between $106,000 and $394,000: IRMAA is $406.90, bringing the total premium to $591.90.
• Income over $394,000: IRMAA is $443.90, resulting in a total premium of $628.90.

Married Filing Jointly:

• Income of $212,000 or less: No IRMAA applies, and the standard premium is $185.
• Income between $212,000 and $394,000: IRMAA is $406.90, for a total premium of $591.90.
• Income over $394,000: IRMAA is $443.90, with a total premium of $628.90.

There is also some additional cost-sharing that you should consider. The annual deductible for Part B is $257 in 2025. After your deductible has been met for the year, you will typically be required to pay 20% of Medicare-approved costs for healthcare services.

If you have a Medicare Supplement plan, you can get help with these costs to reduce out-of-pocket expenses. 

Important to note: If you delay enrollment in Part B without having other qualifying coverage, you may face a late enrollment penalty. This penalty is a permanent increase in your monthly premium, calculated as 10% for every full 12-month period you were eligible but did not sign up.

Who Is Eligible for Medicare Part B?

Medicare Part B is available to individuals who meet specific age, residency, or disability criteria.

Below is a clear overview of who is eligible to enroll.

Age-Based Eligibility

You are eligible for Medicare Part B if:

• You are 65 years or older
• You are a U.S. citizen or a legal permanent resident who has lived in the United States for at least five continuous years

Most people in this group qualify automatically and can enroll in Medicare Part A and Part B when they turn 65. If you’re already receiving Social Security or Railroad Retirement benefits at that time, enrollment is automatic.

Disability-Based Eligibility

You are also eligible for Medicare Part B before age 65 if:

• You have been receiving Social Security Disability Insurance (SSDI) for 24 consecutive months
• You have been diagnosed with End-Stage Renal Disease (ESRD) and require dialysis or a kidney transplant
• You have been diagnosed with Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig’s disease (in which case Medicare starts the same month your disability benefits begin)

How to Enroll in Part B

Unlike Medicare Part A, which you can enroll in at any time if you qualify for premium-free coverage, Medicare Part B has specific enrollment periods and cannot be signed up for at any time.

Here’s a breakdown of the key enrollment periods for Medicare Part B:

Initial Enrollment Period (IEP): You have a seven-month window to sign up for Medicare Part A, Part B, or both. This period begins three months before the month you turn 65, includes the month of your 65th birthday, and extends three months after. To avoid delays in coverage or potential gaps, enrolling during the first three months of your IEP is best. Waiting until your birthday month or later could result in delayed coverage. Failure to enroll during this period may also lead to a late enrollment penalty for Medicare Part B.

General Enrollment Period (GEP): If you miss your Initial Enrollment Period and don’t qualify for a Special Enrollment Period, you can still sign up for Medicare Part B during the General Enrollment Period. This annual window runs from January 1 to March 31, with coverage starting on July 1. However, delaying enrollment until the GEP could leave you without coverage for several months.

Special Enrollment Period (SEP): Certain circumstances allow you to enroll in Medicare Part B outside the standard windows. If a group health plan covers you through your employer or your spouse’s employer, you qualify for a continuous Special Enrollment Period and can enroll in Medicare Part B at any time if eligible. If your job ends, you retire, or your group health coverage ends for another reason, you’ll have an eight-month Special Enrollment Period to sign up for Medicare Part B without penalty.

Understanding these enrollment periods is crucial to ensuring consistent health coverage and avoiding unnecessary penalties. Plan and enroll during the appropriate time to make the transition to Medicare Part B as smooth as possible.

How Do I Pay for Medicare Part B?

Paying for Medicare Part B is straightforward, but the method can vary depending on whether you receive Social Security or Railroad Retirement Board (RRB) benefits.

Here’s how it works:

If You Receive Social Security or RRB Benefits

Your Medicare Part B premium is automatically deducted monthly from your Social Security or Railroad Retirement benefit payment. You don’t need to act unless your benefits change or you stop receiving them.

If You Do Not Receive Social Security or RRB Benefits

If you’re enrolled in Part B but don’t receive Social Security or RRB benefits, you’ll receive a bill for your premiums every three months. This is called a “Medicare Premium Bill” (Form CMS-500).

You have several options for paying:

• Online through your Medicare account: You can log in at medicare.gov and use the “Pay my premium” option with a credit card, debit card, or bank account.
• Medicare Easy Pay: This is a free service that automatically deducts your premium from your bank account each month. You can sign up by completing a form available on the Medicare website or by calling 1-800-MEDICARE.
• Mailing a check or money order: You can send payment to the address listed on your Medicare bill using the payment coupon included. Be sure to include your Medicare number on the check.
• Online banking/bill pay: You can also use your bank’s bill pay service to send your payment, making sure to include your Medicare number as the account number.

Important to know: If your premium isn’t paid by the due date, Medicare will send you a second bill. If that also goes unpaid, you risk losing your coverage. It’s important to stay current with payments to avoid interruptions.

Can I Drop Part B if I No Longer Want It?

Yes, you can drop Medicare Part B if you no longer want it, but it’s important to understand the potential consequences and the process involved.

You might consider dropping Medicare Part B if you have other health coverage, such as an employer plan, a spouse’s plan with creditable coverage, or VA benefits. It could also make sense if you want to reduce expenses, but be aware of potential trade-offs.

You cannot drop Part B online or over the phone. The process must be done in writing and involves the following steps:

• Contact the Social Security Administration (SSA) and request Form CMS-1763, Request for Termination of Premium Hospital and/or Supplementary Medical Insurance.
• You will typically need a personal interview with a Social Security representative, either in person or by phone. This interview is required to ensure you understand the implications of canceling your coverage.
• After the form is processed, your Part B coverage will end at the start of the following month or a future month you select.

Before dropping Part B, consider that re-enrollment may be delayed, coverage could be affected, and you may face a lifetime late enrollment penalty of 10% for every 12 months without coverage. It might also impact other plans like Medigap or Medicare Advantage.

Pro tip: If you’re considering dropping Part B, it’s a good idea to talk with a Medicare specialist or insurance agent to ensure you won’t lose essential coverage or face financial penalties.

Bottom Line

Medicare Part B is critical to your healthcare coverage once you’re eligible for Medicare. It offers access to various outpatient and preventive services that help maintain your health and manage chronic conditions.

While costs are involved, including monthly premiums and coinsurance, Part B’s benefits can help reduce the financial burden of unexpected medical needs.

Enrolling at the right time and understanding how it fits with other Medicare options will ensure you receive comprehensive care without gaps in coverage.

If you’re considering ways to enhance your Medicare benefits, such as adding a Medigap or Medicare Advantage plan, we can help you compare those options based on your needs.

Article Sources: Medicare.gov | CMS.gov

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