Home/Glossary/Annual Election Period (AEP)Glossary · EnrollmentAnnual Election Period (AEP)October 15 through December 7 each year, when you can switch between Original Medicare and Advantage, change MA plans, or change Part D plans.Related TermsInitial Enrollment Period (IEP)General Enrollment PeriodSpecial Enrollment Period (SEP)Medicare Advantage Open Enrollment (MA-OEP)SHIPLate Enrollment PenaltyCOBRAEmployer Group Health Plan← Back to glossary index