If you want to change Medicare Advantage (Medicare Part C) or Medicare Part D (prescription drug coverage) plans, the best time to do so is during the Annual Election Period (also called Open Enrollment Period), which runs from October 15 to December 7 each year. During that period, you can:

1. Change from Original Medicare, Part A and Part B, to a Medicare Advantage plan.

2. Change from a Medicare Advantage plan back to Original Medicare, Part A and Part B.

3. Switch from one Medicare Advantage plan to another.

4. Switch from a Medicare Advantage plan that doesn't offer drug coverage to a Medicare Advantage plan that does.

5. Switch from a Medicare Advantage plan that offers drug coverage to a Medicare Advantage plan that doesn't.

6. Switch from one Medicare Prescription Drug Plan (Part D) to another.

When you change Medicare plans during the Annual Election Period, your new coverage begins on January 1 of the following year.