Know which enrollment decision you are making.

The Initial Enrollment Period for someone first eligible at 65 generally spans seven months around the birthday month. Other eligibility situations and current employment can change the relevant pathway.

Confirm the period and start date with Medicare or Social Security. Having an application in progress is not the same as having active coverage.

This yearly window allows changes between Original Medicare and Medicare Advantage, a different Medicare Advantage plan, or separate drug coverage where applicable. Coverage generally begins January 1 of the next year if the plan receives the request by December 7.

Check the upcoming year’s care access, prescriptions, costs and plan documents before changing. This window does not enroll you in Medicare Parts A and B or guarantee that you can buy Medigap. Separate enrollment and buying protections apply.

People already enrolled in Medicare Advantage can make one change: switch to another Medicare Advantage plan, with or without drug coverage, or return to Original Medicare and add a separate drug plan. The change generally begins the first day of the month after the plan receives the request.

This period does not allow people in Original Medicare to join Medicare Advantage or switch stand-alone drug plans. People who choose Medicare Advantage when first getting Medicare have a separate first-three-month opportunity. Confirm which window applies before acting.

A Special Enrollment Period may allow changes after certain life events, such as moving or losing qualifying coverage. The allowed action and deadline depend on the event.

Prepare the exact event date and any supporting notice. Do not assume that an advertisement, a change of preference or veteran status by itself creates an enrollment opportunity.

The federal Medigap Open Enrollment Period is a one-time period tied to being 65 or older and enrolled in Part B. Outside it, guaranteed-issue rights or additional state protections may matter.

A Medicare plan-change opportunity does not automatically mean a Medigap insurer must issue a policy. Confirm those rights before dropping existing supplemental coverage.