What You Need to Know About Medicare: Medicare Part B

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Medicare Part B is the “medical insurance” portion of Medicare. Medicare Part B coverage is paid for by a monthly premium that is based on your Modified Adjusted Gross Income (MAGI) from two years before you enroll. If you are receiving Social Security and do not want Part B, you must opt-out; otherwise, you will be automatically enrolled and the premium will be deducted from your Social Security check. (1)

If you do not sign up for Medicare Part B when you are first eligible, you may pay a late enrollment penalty of 10% for each full 12-month period that your application was delayed. This penalty lasts for as long as you have Medicare. (The penalty does not apply if you or your spouse are still working and covered by medical insurance through work.) This means that each year of delayed filing can add up to $50.49 per month (as of 2021) per person to the premiums for life. While this amount may not sound like a lot, it adds up to $18,176 per person over a 30-year time span.  

The open enrollment period for Part B is between October 15th and December 7th every year during which time you can change plans. Any changes made during the general enrollment period will go into effect January 1st of the following calendar year. 

If you did not enroll for Medicare Part B during your initial enrollment period, there is another chance for you to do so during the general enrollment period starting January 1st and ending March 31st, although penalties may apply. Enrolled coverage made during the general enrollment period begins July 1st of the same calendar year. (2) 


Benefit Coverage

Medicare Part B helps pay for some of the products and services not covered by Part A.  After your monthly premium and a $203 deductible (as of 2021), Part B coverage generally requires a 20% copayment (3) of patient bills and can include the following:

  • X-rays
  • Canes
  • Influenza & Pneumonia Vaccinations
  • Blood Transfusions
  • Renal Dialysis
  • Outpatient Hospital Procedures
  • Outpatient Mental Health (may require an additional 20%–40% co-pay)
  • Clinical Research
  • In Some Cases, Occasional Home Healthcare Services (0% co-payment)
  • Immunosuppressive Drugs (for organ transplant recipients)
  • One Pair of Eyeglasses (following cataract surgery)
  • Medication (administered by a physician during an office visit)
  • Lab & Diagnostic Tests (some lab services do not require a co-pay)
  • Walkers
  • Wheelchairs
  • Mobility Scooters
  • Prosthetic Devices
  • Oxygen
  • Chemotherapy
  • Limited Ambulance Transportation

Keep in mind that Medicare has decided what they will pay for specific services; if your doctor accepts what Medicare pays, it is said that they “accept assignment.” If the doctor chooses to charge more than Medicare pays, you will have to pay the difference.


  1. “Medicare 2020 Costs at a Glance.” www.medicare.gov, “Part B Costs.” www.medicare.gov, www.medicare.gov/your-medicare-costs/part-b-costs/part-b-costs.html.
  2. “Medicare Part B (Medical Insurance).” www.medicare.gov, www.medicare.gov/pubs/pdf/11036-Enrolling-Medicare-Part-A-Part-B.pdf.
  3. “Part B Costs.” www.medicare.gov, www.medicare.gov/your-medicare-costs/part-b-costs/part-b-costs.html.