Navigating Medicare can feel daunting, especially if you are new to the system. Understanding what each part covers and which benefits you’re entitled to, however, can help you choose a plan that fits both your healthcare needs and your budget.
Here’s what you need to know about Medicare Part B.
What Is Medicare Part B?
Medicare Part B is the portion of Medicare that helps cover medically necessary outpatient services and care, such as:
— Visits to the doctor
— Certain home health services
— Lab and imaging services
— Vaccines
Together, Medicare Part A, which covers inpatient hospital care, and Part B are known as “original Medicare” or “traditional Medicare.”
[Read: How to Choose a Medicare Plan: 5 Essential Steps]
Medicare Part B Eligibility
You are eligible for Medicare Part B if:
— You are a U.S. citizen or legal permanent resident who has lived in the United States for at least five continuous years.
— You are age 65 and older.
— You are younger than 65, but you have received Social Security Disability benefits for 24 months.
— You have end-stage renal disease or amyotrophic lateral sclerosis, also known as ALS.
[SEE: Preventing Costly Medicare Mistakes: Tips and Strategies]
Applying for Medicare Part B
You can apply for Medicare Part B when you first become eligible, during what’s known as the initial enrollment period. This period stretches from three months before you turn 65 to the month of your birthday and three months afterward.
You can enroll in Medicare by:
— Applying online through the Social Security Administration’s website
— Calling 1-800-772-1213
— Visiting a local Social Security office
If you are already receiving Social Security payments — and are thus eligible for Medicare parts A and B — the government automatically enrolls you prior to your 65th birthday.
If you miss your initial enrollment window, you can sign up for Medicare during the general enrollment period (January 1 to March 31 every year) or during a special enrollment period, if you qualify.
Do you have to enroll in Medicare Part B?
Part B is optional and you can decline it, but most people choose to enroll when first eligible. If you delay signing up and do not have other creditable coverage like insurance through your job, you may face a late enrollment penalty of 10% for every year without coverage. However, if you do have what Medicare considers creditable coverage, you are eligible for a special enrollment period when that coverage ends and you won’t face late penalties. If you are 65 or older, still working and not yet drawing Social Security, the key determinant for enrolling in Medicare is the size of your employer. If the company has fewer than 20 employees, you should enroll during the initial enrollment period.
There are two reasons for enrolling, according to Edd Staton, a retirement expert and co-author of the book “Mission: Rescue Your Retirement”:
— Your small group insurer might be able to refuse to pay any portion of claims that Medicare would have paid.
— Whenever you do enroll in Medicare, you will be subject to a lifelong late enrollment penalty on Part B that continues to increase every year you delay.
“Also, if you are contributing to a health savings account, you cannot enroll in Medicare because to contribute pretax dollars, you cannot have health insurance other than a high-deductible health plan,” Staton explains.
If you do have employer coverage, you can sign up for Medicare without a penalty after you retire. Once you’re enrolled, keep in mind that you are no longer eligible to contribute to a health savings account.
[READ: Understanding the Medicare Part B Giveback Benefit]
Medicare Part B vs. Employer Coverage: 2026 Rule of Thumb
To understand your original Medicare enrollment options, let’s walk through some scenarios.
| Your Situation | Action for Part A | Action for Part B | The Reason |
| Already on Social Security | Automatic enrollment | Automatic enrollment | Medicare assumes you are retired and need full coverage. |
| Postponing Social Security until ages 67-70 | Must apply | Must apply | Delaying Social Security does not delay your Medicare eligibility. You must sign up at 65. |
| Working (at a small company with fewer than 20 employees) | Must apply | Must apply | Medicare is “primary.” Your work insurance may pay $0 until you have Part B. |
| Working (at a large company with more than 20 employees) | Usually apply | Delay | You can save the monthly premium and join later via a special enrollment period. |
| Active HSA contributor | Delay both | Delay both | Warning: Enrolling in Part A or Part B makes you ineligible to contribute to an HSA. |
Part B Out-of-Pocket Costs in 2026
Like most employer-based or healthcare exchange insurance plans, Medicare uses premiums, deductibles and other out-of-pocket expenses, such as copays and coinsurance, to help cover the cost. These costs fluctuate every year; below are the differences between 2025 and 2026.
| Expense Category | 2025 Amount | 2026 Amount | Change |
| Standard monthly premium | $185 | $202.90 | + $17.90 |
| Annual deductible | $257 | $283 | + $26 |
| Coinsurance | 20% | 20% | No changes |
| IRMAA minimum total | $259 | $284.10 | Applies if your income is more than $109,000 |
How your Part B costs work
The different pieces you’re responsible for vary slightly:
— Premium ($202.90): Most people pay the standard premium, which is typically deducted from your Social Security benefit checks. If you don’t get these benefits, or they’re insufficient, Medicare will bill you.
— Deductible ($283): Under original Medicare, if the Part B deductible applies, you must pay all costs until you meet it.
— Coinsurance (20%): After you meet your deductible, Medicare begins to pay its share, typically 80%. You pay the remaining percentage of the Medicare-approved amount of the service. Keep in mind that there’s no yearly limit on what you pay out-of-pocket if you have original Medicare. To help cover those out-of-pocket costs, many sign up for a Medicare supplement plan, also known as Medigap.
Income surcharges (IRMAA) and financial assistance
Your costs may also be lower or higher depending on your income.
— Lower: You may qualify for Medicare-Medicaid dual eligibility or one of the Medicare Savings Programs for financial assistance with out-of-pocket costs. Eligibility for financial assistance programs vary by state. “The qualification process is more accessible in some states due to elevated income limits or the absence of asset requirements,” says Mary Johnson, a Medicare policy analyst with the Senior Citizens League.
— Higher: The income-related monthly adjustment amount (IRMAA) is an additional surcharge added to your standard premium if your income exceeds certain thresholds. IRMAA is calculated using your modified adjusted gross income from two years prior. For example, your 2024 tax return determines your 2026 premiums, which means Medicare’s calculation may not reflect your current income, often catching beneficiaries by surprise. If you disagree with your IRMAA determination or your income has dropped due to a qualifying life event — retirement, reduced work, divorce or the death of a spouse — you have the right to appeal the surcharge.
2026 IRMAA income tier table
| Individual Tax Return | Joint Tax Return | Married Filing Separately | Total Monthly Premium (2026) |
| $109,000 or less | $218,000 or less | $109,000 or less | $202.90 |
| $109,001 — $137,000 | $218,001 — $274,000 | N/A | $284.10 |
| $137,001 — $171,000 | $274,001 — $342,000 | N/A | $405.80 |
| $171,001 — $205,000 | $342,001 — $410,000 | N/A | $527.50 |
| $205,001 — $499,999 | $410,001 — $749,999 | $109,001 — $390,999 | $649.20 |
| $500,000 or more | $750,000 or more | $391,000 or more | $689.90 |
New 2026 Coverage Highlights
Medicare coverage continues to evolve in 2026, with changes reflecting a broader shift toward prevention, chronic disease management, strengthened cost control and whole-person care. The higher costs for beneficiaries are due to Medicare’s overall rising expenses, driven by increasing enrollment, longer life expectancy, more chronic conditions, higher prescription drug costs and increased use of outpatient care.
Advanced primary care management
Advanced Primary Care Management (APCM) is a new Medicare Part?B care model designed to support more proactive, coordinated care for beneficiaries, especially those with chronic conditions. Unlike traditional models that focus on episodic office visits when necessary, under APCM, providers are incentivized to manage a patient’s overall health needs. This approach includes 24/7 access to a care team, chronic care management, a personalized care plan, medication management and care coordination across providers and settings.
With this shift to more personalized, coordinated health management, the goal is to better support beneficiaries’ overall health, manage chronic conditions more effectively, catch minor issues before they escalate and help avoid unnecessary hospital or emergency room visits.
Drug price negotiation program
While the lower prices won’t take effect until 2028, this year Medicare is expanding its price negotiation program to include Part B physician-administered drugs for the first time. This initiative will reduce the 20% coinsurance patients typically pay for high-cost infusions and injections, such as Entyvio (for autoimmune conditions), Xolair (for respiratory issues) and Botox (for certain chronic medical conditions).
The aim is to make these high-cost drugs more affordable for beneficiaries while also containing overall rising costs and helping to protect the program’s long-term sustainability.
Expanded behavioral health coverage
Medicare is strengthening its mental health coverage by making telehealth visits a permanent benefit. The in-person visit requirement, which dictates how often you must see a doctor face-to-face to maintain telehealth coverage, has been waived through 2027 to ensure access for rural and homebound patients with mental healthcare needs.
Proactive prevention is also expanding with $0 group obesity counseling and enhanced annual wellness screenings for depression, anxiety and cognitive health. Medicare also increased reimbursement for key mental and behavioral health services, helping encourage more providers to accept Medicare patients and improve access to care.
Part B premium increase
In 2026, the standard Medicare Part B premium rose sharply, marking the third consecutive year that premiums have increased faster than Social Security’s cost-of-living adjustment, making affordability a challenge for many on a fixed income.
“Affording healthcare expenses, even with Medicare, is increasingly a struggle for many seniors,” Johnson says.
Federal law mandates that Part B premiums cover exactly 25% of the program’s total costs, so any significant increases in medical spending by the program translates directly into higher monthly bills for seniors.
Wasteful and inappropriate service reduction (WISeR) model
For those with original Medicare, the WISeR model is a new Medicare pilot that requires prior authorization for certain outpatient services in Part B if you live in Arizona, New Jersey, Ohio, Oklahoma, Texas or Washington. This model combines AI and clinical oversight to streamline the prior authorization process, with the goal to reduce usage of specific low-value or unnecessary services and lower overall costs and improve patient safety. This won’t change your benefits overall; it just changes how some services are approved. This also does not affect anyone enrolled in a Medicare Advantage plan (also known as Medicare Part C).
What Doesn’t Medicare Part B Cover?
Medicare Part B does not cover:
— Hospital insurance, which falls under the Medicare Part A coverage umbrella, including:
— Inpatient hospitalization
— Skilled nursing facility stays
— Some home healthcare
— Hospice
— Prescription drug coverage, which Medicare Part D covers
— Dental, vision care and hearing aids, which some Medicare Advantage plans cover
— Long-term care
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Medicare Part B Guide: Costs and Coverage originally appeared on usnews.com
Update 07/24/26: This story was previously published at an earlier date and has been updated with new information.
