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Medicare Basics

Medicare Part B is Medical Insurance

Medicare Part B helps pay for doctor's office visits and services, lab tests, and most outpatient care. Most people pay a monthly Part B premium.

Senior woman sitting on counter during a doctor’s visit.

Your Quick Overview of Medicare Part B

Play this short video for a brief overview. You’ll learn essential information about Medicare Part B, and how enrollment works.

With Part B (Medical Insurance):

  • Helps pay for doctor office visits and services, lab tests and most outpatient care.
  • Most people pay a monthly premium for Part B.
  • You can enroll in Part B during your Initial Enrollment Period. This is a 7-month period (the three months before your birthday month, your birthday month, and the three months after your birthday month).
  • If you decline Part B during your Initial Enrollment Period and enroll during the General Enrollment Period, you may pay a penalty. The monthly premium for Part B goes up 10% for each 12-month period that you could have had Medicare but didn’t sign up for it. The penalty increases as Medicare premiums increase.
  • If you decline Part B during your Initial Enrollment Period because of coverage due to active employment for a company with 20 or more employees, you should enroll during your Special Enrollment Period.

Questions About Eligibility and Enrollment?

If you have questions about Medicare Part B, here’s some quick answers for you.

Am I eligible?

You can enroll in Medicare Part B if you:

  • Are retired
  • Are not working
  • Have COBRA or retiree health coverage
  • Have a group health plan that pays second after Medicare pays

If your work status changes, call the Social Security Administration at 1-800-772-1213. Ask how your change in work status may affect your Medicare coverage. TTY users should call 1-800-325-0778.

When can I enroll?

You can enroll in Part B during your Initial Enrollment Period. This is a seven-month period:

  • It starts three months before your birthday month.
  • It includes your birthday month.
  • It ends three months after your birthday month.

What if I don’t enroll during Initial Enrollment?

It’s best if you enroll during the Initial Enrollment Period. Here’s why:

  • If you decline Part B during your Initial Enrollment Period and enroll during the General Enrollment Period, you may pay a penalty.
  • The monthly premium for Part B goes up 10% for each 12-month period that you could have had Medicare coverage but didn’t sign up for it.
  • The penalty increases as Medicare premiums increase.

If you decline Part B during your Initial Enrollment Period because of coverage due to active employment for a company with 20 or more employees, you should enroll during your Special Enrollment Period. If this applies to you, contact us at 1-866-940-3022 (TTY: 711) for information on how to enroll.

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