Medicare Plan Non-Renewal: Every Deadline, in Order

October 15 to December 7: the window everyone knows

You can use the ordinary Annual Enrollment Period like anyone else. Choose a replacement during it and your new coverage starts **January 1** — no gap, clean handoff.

For most people whose plan is ending, this is the simplest route. You are already going to be comparing plans this fall; a plan exit just means you have to, rather than choosing to.

December 8 to the end of February: the window built for this

Because your plan is leaving rather than you choosing to leave, you also get a Special Enrollment Period that the general population does not. For a plan ending on December 31, it runs from **December 8 through the last day of February** — the 28th, or the 29th in a leap year.

The trade-off is the start date. Coverage from a choice made in this window begins the **first day of the month after you enroll**, not January 1. Pick a plan on January 20 and you are covered February 1 — which means January itself has no plan coverage on top of your Original Medicare.

So the two windows do different jobs. Use Annual Enrollment for continuous coverage. Use this one if you need more time to decide, or if January arrives and you realise the replacement you chose was wrong.

One caveat worth stating: these are the dates for a plan ending with the calendar year, which is what a fall non-renewal notice means. A plan terminating mid-year opens a differently timed window, so if your letter names a date other than December 31, confirm your specific window with 1-800-MEDICARE.

The Medigap clock runs on its own schedule

The guaranteed-issue right that a plan termination can open is not tied to either window above. It runs on its own timeline, anchored to when your coverage actually ends rather than to enrollment periods, and it is measured in days rather than months.

That matters because it can close while a Special Enrollment Period is still open. Someone who takes until February to decide may find the Advantage and Part D options still available and the Medigap door shut. If Medigap is on your list at all, treat it as the earliest deadline, not the latest — the guaranteed-issue rights guide has the exact counts.

Putting it on a calendar

In order, for a plan ending December 31:

• **By October 2** — your non-renewal notice should arrive
• **October 15** — Annual Enrollment opens; anything chosen from here through December 7 starts January 1
• **December 7** — Annual Enrollment closes
• **December 8** — your plan-termination Special Enrollment Period opens
• **December 31** — your old plan ends; the Medigap guaranteed-issue clock is anchored around this date
• **Last day of February** — your Special Enrollment Period closes

What to have ready

Whichever window you use, the decision needs the same three things: your complete prescription list with dosages, your pharmacy, and the doctors and hospitals you intend to keep, by name. Nothing carries over from a plan that is ending, so all three have to be checked against whatever you are considering.

Our September checklist covers assembling that, and the Open Enrollment 2027 calendar has every fall date with reminders you can add to your own calendar. If you would rather work through the comparison without an appointment, enroll yourself covers the whole process.