Know your deadlines
Medicare enrollment timeline.
Missing a Medicare deadline can mean penalties or gaps in coverage. Here's a clear look at the enrollment periods that matter most.
Initial Enrollment Period
3 months before, your birth month, and 3 months after you turn 65
Your first chance to enroll in Medicare. This is when most people sign up for Part A and/or Part B, and choose a Medicare Advantage or drug plan.
Annual Enrollment Period
October 15 – December 7, every year
The yearly window when anyone with Medicare can switch, join, or drop a Medicare Advantage or Part D drug plan. Changes take effect January 1.
Open Enrollment Period (Medicare Advantage)
January 1 – March 31, every year
If you're already in a Medicare Advantage plan, you can switch to another Advantage plan or go back to Original Medicare (plus a Part D plan) once during this period.
General Enrollment Period
January 1 – March 31, every year
If you missed your IEP and didn't qualify for a Special Enrollment Period, you can enroll in Part A and/or Part B now — though late penalties may apply.
Special Enrollment Period
Triggered by life events
Certain events — like losing employer coverage, moving, or losing Medicaid — can qualify you to enroll or change plans outside the standard windows.
Not sure which period applies to you?
I'll help you figure out your exact window and avoid late penalties — at no cost.