Medicare open enrollment runs October 15 to December 7 each year, per Medicare.gov, with changes effective January 1.
In that window you can switch between Original Medicare and Advantage, change Advantage plans, or join, drop, or switch Part D drug plans. Review even if satisfied: formularies, networks, and premiums change yearly. Other windows: your 7-month Initial Enrollment Period around age 65, the January 1 to March 31 Advantage-only switching period, and Special Enrollment Periods for life events. Each fall, run your medications and doctors through the Medicare plan finder and switch if the math favors it.
What to do
Common questions
When is open enrollment for Medicare?
The Medicare fall open enrollment window is fixed: October 15 through December 7 each year, per Medicare.gov, and whatever you change takes effect January 1, as long as the plan gets your request by December 7. What you can do in that window: switch between Original Medicare and a Medicare Advantage plan in either direction, change from one Advantage plan to another, and join, drop, or switch a Part D prescription drug plan. It is worth using even if you are happy, because plans reprice and reshuffle drug formularies and networks every year, and the plan that was cheapest for your medications this year can quietly become expensive next year. The other windows to know: your Initial Enrollment Period, the 7-month window around your 65th birthday when you first sign up; the Medicare Advantage Open Enrollment Period from January 1 to March 31, when people already in an Advantage plan can switch Advantage plans or go back to Original Medicare; and Special Enrollment Periods for life events like moving or losing other coverage. The practical move each fall: list your medications and doctors, run them through the plan finder on Medicare.gov, and switch if the math says switch. Loyalty to a plan costs real money in Medicare.