Know the timing windows that affect Medicare decisions

Medicare Open Enrollment runs October 15 through December 7. Eligible changes to Medicare Advantage or Part D generally start January 1 of the following year.

Medicare Advantage Open Enrollment runs January 1 through March 31 for people already in Medicare Advantage. It permits a switch to another Medicare Advantage plan or a return to Original Medicare with the option to join a separate drug plan.

Medigap has separate buying rights. The federal six-month Medigap Open Enrollment Period begins when you are at least 65 and enrolled in Part B. It is not an annual fall window; additional state protections or guaranteed-issue rights may apply.

When you are first becoming eligible for Medicare, your initial enrollment timing usually deserves the most attention. That is often when people are deciding whether to move into Medicare now, how Part B fits in, and which coverage path they want to compare.

If you are already enrolled, annual review periods can become important when provider access, prescriptions, or plan details change. That is often when people compare whether their current coverage still fits the next year.

Some life and coverage changes can create special timing windows. Because those situations vary, it helps to slow down and confirm which rules apply before you assume you have to make a decision immediately.

People still working past 65 often need to review how employer coverage works with Medicare before deciding what to do next. That is one reason timing guidance should always be tied to your actual coverage situation.

A calm review of your timing can make the plan comparison better. Once you know the enrollment window that matters, it becomes easier to compare Medicare Advantage, Medicare Supplement, and Part D without feeling pressured.