Medicare has multiple enrollment periods with different rules, and confusing them can leave beneficiaries locked into the wrong plan for months.
The Annual Enrollment Period runs from October 15 to December 7, during which beneficiaries can switch between Original Medicare and Medicare Advantage, or change Part D plans.
The Medicare Advantage Open Enrollment Period runs from January 1 to March 31, but is more limited — beneficiaries can only switch from one Medicare Advantage plan to another, or drop Medicare Advantage and return to Original Medicare.
Outside these windows, Special Enrollment Periods may apply for beneficiaries who move, lose employer coverage, or qualify for a Special Needs Plan. Understanding which enrollment period applies can save beneficiaries from costly mistakes.





