Source data
Medicare enrollment windows, deadlines and effective dates
Sources checked
- 15 October 2026Medicare Open Enrollment starts for 2027 plan choices.
- 7 December 2026A plan must receive the fall enrollment request for January 1 coverage.
- 1 January 2027Changes made through fall Open Enrollment take effect. Two other enrollment windows begin.
- 31 March 2027Medicare Advantage Open Enrollment and General Enrollment both end.
The two windows beginning January 1 have different eligibility.
Medicare enrollment windows, deadlines and effective dates
The calendar includes annual plan changes, first-time enrollment and selected enrollment routes. Eligibility and effective dates depend on which route applies.
| Source | ||||
|---|---|---|---|---|
| Fall Medicare Open Enrollment for 2027 plans | 15 October 2026 | 7 December 2026 | 1 January 2027 | Source 1 |
| Medicare Advantage Open Enrollment | 1 January 2027 | 31 March 2027 | First day of the month after the plan receives the request | Source 2 |
| General Enrollment for Part B or premium Part A | 1 January 2027 | 31 March 2027 | First day of the month after sign-up | Source 3 |
| Initial Enrollment for Part A and Part B around age 65 | Usually three months before the month of the 65th birthday | Usually three months after the month of the 65th birthday | Depends on part, premium status, birthday and sign-up month | Source 3 |
| Plan change for a new Medicare Advantage member who joined during initial enrollment | When the member first has both Part A and Part B | Within the first three months of having both Part A and Part B | Generally the first of the month after the plan receives the request | Source 2 |
| Special Enrollment for a health or drug plan | Depends on the qualifying event | Depends on the qualifying event | Generally the first of the month after the plan receives the request | Source 2 |