Medicare Glossary

Disenrollment

The process of leaving a Medicare Advantage or Part D plan. You can only disenroll during specific enrollment periods, such as the Annual Enrollment Period or a Special Enrollment Period. When you disenroll from a Medicare Advantage plan, you return to Original Medicare.

Service Area

The geographic area where a Medicare Advantage or Part D plan is available and provides coverage. Plans may have different networks and costs in different parts of their service area. Moving outside a plan's service area may trigger a Special Enrollment Period.

Special Enrollment Period (SEP)

A window outside the standard enrollment periods during which you can join, switch, or drop a Medicare plan. SEPs are triggered by qualifying life events such as losing employer coverage, moving, gaining Medicaid eligibility, or your plan leaving the area.

Also known as: SEP