Medicare Open Enrollment runs October 15 through December 7 each year. In 2026, Medicare Advantage and Part D changes made during this period generally take effect January 1, 2027.
What you can review or change
- Change from Original Medicare to a Medicare Advantage plan
- Change from Medicare Advantage back to Original Medicare
- Switch Medicare Advantage plans
- Join, switch, or drop a Part D drug plan
Open Enrollment is not a recurring Medigap enrollment period. Medigap eligibility and underwriting rules are different and may include state protections.
Prepare before October 15
- Read your Annual Notice of Change.
- List every prescription, dose, and preferred pharmacy.
- List your doctors, hospitals, and other providers.
- Consider expected care, travel, and time away from home.
- Verify 2027 costs, networks, formularies, and plan rules in official plan documents.
- Talk with an employer or union benefits administrator before changing related coverage.
Before October 15, prepare and compare. Do not describe a person as able to enroll early unless another valid enrollment period applies.
Would you like help sorting through your choices?
Reviewed by BGA’s in-house compliance team. Last reviewed August 24, 2026. Effective year: 2027 coverage.