Medicare Glossary

Definitions for common Medicare terms

Medicare open enrollment

DEFINITION: Medicare open enrollment – also known as the annual election period or annual coordinated election period  – refers to the annual period during which Medicare plan enrollees can reevaluate their coverage — whether it’s Original Medicare with supplemental drug coverage, or Medicare Advantage — and make changes if they want to do so.

During Medicare open enrollment, a beneficiary can switch Medicare Advantage plans, switch from Medicare Advantage back to Original Medicare or vice versa, join a Medicare Part D prescription drug plan, switch from one Part D plan to another, or drop Medicare Part D coverage entirely. But the annual open enrollment does not apply to Medigap plans, which are only guaranteed-issue in most states during a beneficiary’s initial enrollment period, and during limited special enrollment periods.

Medicare open enrollment begins on October 15 and ends on December 7, with changes effective on January 1.