Each Special Enrollment Period has its own trigger, its own length and its own list of allowed changes. Most last 2 full months after the event. Some last 3 months, two can be used once a calendar month, and the 5-star one can be used once a year. None of them is the Annual Enrollment Period, which runs October 15 to December 7, 2026 for everyone with Medicare. These are the Medicare rules. The Health Insurance Marketplace has separate Special Enrollment Periods of its own, with different events and deadlines.
| What happened | What you can do | How long you have |
|---|---|---|
| You moved out of your plan’s service area | Join a plan where you now live, or go back to Original Medicare | Until 2 full months after the move |
| Your employer or union coverage ended, including COBRA | Join a Medicare Advantage or Part D plan | 2 full months after the month it ends |
| You lost Medicaid | Join, switch or drop drug coverage | 3 full months |
| You have Medicaid or get Extra Help | Switch drug plans, or leave Medicare Advantage for Original Medicare and a drug plan | Once each calendar month |
| A 5-star plan serves your area | Switch into that plan | Once between December 8 and November 30 |
| Your plan is not renewed | Choose another plan | December 8 to the last day of February |
How it works
You do not apply for a Special Enrollment Period in advance. You use it by enrolling in a new plan and saying which event qualifies you, and the plan may ask you to show it, so keep the paperwork: the letter that says your employer coverage ended, a lease or bill at your new address, or the Medicaid notice. Coverage usually starts the first day of the month after the plan gets your request.
The ones people miss
Three are easy to overlook. If you have Medicaid or Extra Help, you can change drug coverage once a month, with the change starting the first of the next month, unless your plan has flagged you as at risk under a drug management program. If you learn you will not get Extra Help next year, you get 3 months to change plans. And if a plan with a 5-star overall rating serves your area, you can switch into it once between December 8 and November 30, but moving from a plan with drug coverage to a 5-star plan without it can leave you with no drug coverage and a late enrollment penalty.
What to do next
Write down the date of the event and count forward, because most windows close 2 full months later and missing one usually means waiting for Annual Enrollment. If nothing on the list fits but you were given misleading information when you joined a plan, or your plan’s provider network changed significantly, Medicare decides those case by case, and we can help you put the request together. If you are leaving a job’s coverage, plan the switch before that coverage ends so there is no gap.
Read the full guide: Every Medicare enrollment period, explained
Related questions
Is a Special Enrollment Period the same as Annual Enrollment?
No. Annual Enrollment is open to everyone with Medicare from October 15 to December 7. A Special Enrollment Period is open only to people who had a qualifying event, and only for as long as that event allows.
Does moving within Broward County give me one?
Only if your new address is outside your plan’s service area or gives you plan options you did not have before. A move to a home where the same plans are offered does not open one.
Do Marketplace plans follow the same rules?
No. HealthCare.gov runs its own Special Enrollment Periods for Marketplace coverage, with different qualifying events and deadlines.
Sources
- Special Enrollment Periods — Medicare.gov (CMS) · read 2026-10-30
- Joining a plan — enrollment periods — Medicare.gov (CMS) · read 2026-10-13
This page explains published rules and figures, with the source for each one. It is not advice about your own situation.