When You Can Enroll in Medicare

To enroll in Medicare, most people need to contact Social Security directly. It is recommended you do this before your 65th birthday to avoid lapse in coverage and avoid any penalties for applying late. You should receive a packet in the mail from Medicare before you turn 65. You can enroll online, in person at the Social Security office or by calling 1-800-772-1213.

You have a seven-month window around your 65th birthday to enroll; this is called your initial enrollment period. After that, you can still enroll in Medicare, but you may need to wait for a designated special/general enrollment period to do so. See below for details on the different enrollment periods.

Initial Enrollment Period

  • This is the seven-month time frame surrounding the month of your 65th birthday.
  • You can start applying for Medicare three months before your birthday month. (For example, if your birthday is July 15, you can apply beginning April 1 and your coverage would start July 1.)
  • You can enroll in all four parts during this period.

Special Enrollment Period

This enrollment period applies:

  • If you choose to keep your existing employer-provided health insurance past your 65th birthday
  • Eight months after coverage for Parts A and B end
  • 63 days after coverage for Parts C and D end

General Enrollment Period

  • If you missed the Initial or Special Enrollment periods, you can still sign up for Medicare Parts A and B during General Enrollment between Jan. 1 and March 31 of every year.
  • If you apply for coverage during General Enrollment, it will take effect July 1 of that year. You may face higher premiums and possible fees for late enrollment.

Open Enrollment Period

  • This enrollment period runs from Oct. 15 to Dec. 7 each year.
  • This applies to anyone who is eligible for Medicare and is the time when you can make changes to your coverage.
  • During this time, you can sign up for Parts C and D. This includes switching from Parts A and B to Part C, or from Part C to Parts A and B.
  • If you apply for coverage during Open Enrollment, it will take effect Jan. 1 of the following year.

Medigap Open Enrollment Period

  • This enrollment period is only for Medigap coverage.
  • It runs for six months and starts the month of your 65th birthday AND when you’ve signed up for Medicare Part B.
  • If you don’t sign up during open enrollment, other restrictions will apply.