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When You Can Enroll in Medicare

To enroll in Medicare, most people need to contact Social Security directly. It’s 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 800-772-1213.

You have a 7-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.

  • 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 (Medicare Parts A, B, C and D) during this period.

These occur based on certain life events, such as:

  • Moving
  • Loss of current coverage
  • Opportunity to get other coverage
  • 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.
  • 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.
  • This enrollment period runs from Jan. 1 to March 31 each year.
  • Applies only if you’ve already enrolled in a Medicare Advantage Plan.
  • You can switch to either a different Medicare Advantage Plan or switch to Original Medicare (and join a separate drug (Part D) plan once during this time).
  • During this period, you cannot:
    • Switch from Original Medicare to a Medicare Advantage Plan
    • Join a Medicare drug plan (“Part D Plan”) if you’re already in Original Medicare
    • Switch from one Medicare drug plan to another if you’re in Original Medicare

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.
  • 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.

Information updated November 11, 2021.

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