Every year, this period begins on October 15 and ends on December 7. If you are an existing Medicare beneficiary, you can use this period to reevaluate and make changes to any Medicare Advantage (Part C) and Medicare prescription drug plan (Part D). Coverage will begin on January 1 of the following year.
You cannot use AEP to enroll in Original Medicare, known as Part A and Part B, for the first time.