The answer
What is AEP in Medicare?
AEP stands for the Annual Enrollment Period, the yearly window when anyone with Medicare can make changes to their coverage.
It runs from October 15 to December 7 (2026), and the changes you make take effect January 1 of the following year. During AEP you can join, switch, or drop a Medicare Advantage plan (Part C), join, switch, or drop a Part D prescription drug plan, and move between Original Medicare and Medicare Advantage. This is the main once-a-year opportunity to review your plan against your current doctors, medications, and budget, since plans can change their costs and coverage each year. AEP is different from the Medicare Advantage Open Enrollment Period, which runs January 1 to March 31 (2026) and only lets people already in a Medicare Advantage plan make one switch. If you want to change plans, AEP is usually the time to do it.