Medicare Part B – Medical Insurance

Medicare Part B – General Coverage Information

Medicare Part B is “Medical Insurance” that helps cover the costs of medically necessary services and preventive services. There is a monthly premium for Part B, and if you delay signing up for Part B past your initial enrollment period (when you are first eligible for Part A), you may have to pay late enrollment penalties. Most beneficiaries pay a standard premium, which is $104.90 in 2013, and an annual deductible, which is $147 in 2013. (Some people may pay more based on their IRS tax returns.)

It is an important part of your Medicare health care coverage options, so let’s look a little closer at Part B benefits.

Medically necessary services and supplies are those that a doctor or provider deems necessary to diagnose or treat a medical condition. These services and supplies must be ordered by your physician and have to meet accepted standards of medical practice. These services and supplies can include, but are not limited to: clinical research, ambulance services, mental health services, and durable medical equipment. Durable medical equipment (DME) includes supplies used in your home for a specific medical reason, such as crutches, home oxygen equipment, hospital beds, walkers, wheelchairs, blood sugar monitors, and much more.

Preventive services include health care intended to prevent illness or to detect illness at an early stage when treatment is most effective. Medicare offers a variety of preventive services, including the Welcome to Medicare exam, and annual Yearly Wellness Visits. It also includes important screenings, including but not limited to:

  • Bone mass measurements (bone density)
  • Cardiovascular disease screenings
  • Cervical & vaginal cancer screenings
  • Prostate cancer screenings
  • Diabetes screenings
  • Mammograms
  • Colorectal cancer screenings
  • HIV screenings
  • And more

Preventive services also include nutrition therapy, smoking cessation counseling, glaucoma tests, alcohol misuse screenings and counseling, as well as important vaccinations, such as Flu, Hepatitis B, and Pneumococcal shots.

If you are considering enrollment in a Medicare Advantage plan, you must have both Part A and Part B coverage.


You are eligible for Part A and Part B if:

  • You are 64 years of age and 9 months
  • You are under 65 but qualify due to a disability or other condition
  • You have End Stage Renal Disease (ESRD)

Part B is optional, but if you choose to enroll in Part B, you will likely pay a monthly premium. If you do not enroll in Part B when you are first eligible, you may have to pay a late enrollment penalty when you decide to sign up later. This late enrollment penalty could affect the cost of your Part premiums for the duration of your time getting Part B benefits, so it is important to consider this when you are first eligible.


If you already receive benefits from Social Security or the Railroad Retirement Board, you will automatically be enrolled in Part A. Part B is optional. If you are automatically enrolled, you will receive your Medicare card in the mail three months before your 65th birthday, or in the 25th month of your disability benefits. If you do not want Part B, you will need to follow the instructions on the card and send the card back. If you keep the card, you will keep Part B and be responsible for the monthly premiums.

If you sign up for Original Medicare, you have the option of enrolling in Part B. If you choose to receive your Medicare benefits through a Medicare Advantage (MA) plan, you will need to enroll in Part A and Part B and pay a monthly Part B premium.

If you do not enroll in Part B when you are first eligible, you will likely have to pay a late enrollment penalty when you decide to enroll later on. Your monthly premium for Part B may go up 10% for each full 12-month period that you could have had Part B, but didn’t sign up for it.

Special Enrollment Periods

There are special circumstances that may allow you to sign up for Part B outside of regular enrollment periods during a Special Enrollment Period. For example:

  • If you are over 65 and you or your spouse is still working and covered by a group insurance plan, you may enroll in Part B at a later date during an SEP.
  • If you have Part B, but you or your spouse return to work and now have group health coverage from your employer or union, you can sign up for it again in the future during a Special Enrollment Period. Make sure your group health plan coverage is in effect before you drop Part B. In this case, the cost of Part B won’t go up. Please note that when you drop Part B, your coverage ends the next month.

If you have ESRD, you are eligible for a Special Enrollment Period, regardless of how old you are. If your kidneys no longer work and you need regular dialysis or have had a kidney transplant, and one of these applies to you, you may be eligible for an SEP:

  • You’ve worked the required amount of time under Social Security, the Railroad Retirement Board (RRB), or as a government employee.
  • You’re getting or are eligible for Social Security or Railroad Retirement benefits.
  • You’re the spouse or dependent child of a person who has worked the required amount of time* to be eligible for Medicare, or who is getting Social Security or Railroad Retirement benefits.


If you enroll in Part B, you will likely have to pay a monthly premium, and deductible. For example, in 2013, the Part B premium is $104.90, and the yearly deductible is $147.

If your modified adjusted gross income as reported on your IRS tax return from 2 years ago (the most recent tax return information provided to Social Security by the IRS) is above a certain amount, you may pay more. On the other hand, if you have limited income and resources, your state may help you pay for Part A, and/or Part B.