Senior Benefit Assistance is a licensed Medicare agency. This guide was written by our licensed agents in October 2026 to explain the rights a plan cancellation notice gives you, including the guaranteed window to buy a Medigap policy.
In early October, a member in Washington state got the letter: his Medicare Advantage plan posted its cancellation notice and won't be offered in 2027. His reaction might surprise you: he described himself as now free to move back to Medigap without going through underwriting.
A cancellation notice feels like bad news. But federal law turns it into something valuable: a one-time guaranteed right to buy a Medigap policy with no health questions asked. Here's what that means and how to use it.
What the notice triggers
When a Medicare Advantage plan leaves Medicare or stops serving your area, you get a federal guaranteed-issue right for Medigap. In plain English:
- An insurance company must sell you one of the protected Medigap plans sold in your state (A, B, D, G, K, or L, or C or F if you were eligible for Medicare before 2020).
- It cannot refuse you because of your health.
- It cannot charge you more because of your health.
- It must cover your pre-existing conditions.
Outside of this window, in most states, Medigap insurers can ask health questions and turn you down. Someone who's been on an Advantage plan for years and has since developed a heart condition often can't buy a Medigap policy at any price. The cancellation notice erases the questionnaire, once.
The window: 60 days before, 63 days after
You can apply as early as 60 days before your coverage ends and no later than 63 days after it ends. For a plan ending December 31, 2026, that window is November 1, 2026 through March 4, 2027.
Two things about this deadline:
- Apply early. Your new Medigap coverage can't start until the old coverage ends, but applying ahead means the policy is ready on day one. Wait too long and you risk a gap sitting on Original Medicare with no supplement, paying full deductibles and coinsurance out of pocket.
- There are no extensions under federal rules. Miss the 63 days after your coverage ends and the federal protection is gone; the insurer can underwrite you again, and there's no federal appeal. A few states give broader rights or longer windows of their own, so it is worth checking your state's rules.
Choosing your next step
To use the right, you have to take the Medigap route: a Medigap policy only works alongside Original Medicare. But the window itself is counted from the day your old coverage ends, not from what you choose next. If your plan ends December 31, 2026, your guaranteed-issue window runs through March 4, 2027, whatever you decide first.
That does not make the choice casual. Enrolling in a different Medicare Advantage plan and then switching back to Original Medicare in time is complicated, and it leaves very little room to spare. This is the decision to make deliberately: another Advantage plan, or Original Medicare plus Medigap plus a standalone drug plan. Both are legitimate. But if Medigap is the route you want, deciding before your old plan ends is the safest path.
One more detail: Medigap Plan N, often recommended as a lower-cost option, is not on the federal guaranteed-issue list. Under federal rules, an insurer can still underwrite you for Plan N even inside this window, although some states give broader rights than the federal floor. Plan G is on the list.
Don't forget the drug plan
Medigap doesn't cover prescriptions. If you return to Original Medicare, you also need a standalone Part D drug plan, and you need it promptly, because going 63 or more days without creditable drug coverage triggers a permanent late-enrollment penalty. The Special Enrollment Period for a discontinued plan runs December 8 through the end of February, giving you time to choose. Timing matters, though: enroll by December 31 to have drug coverage start January 1. A plan you pick in January does not take effect until February 1, and a February pick until March 1, which leaves a gap month of paying full price for prescriptions.
Keep the letter
The cancellation or non-renewal notice is your proof. Keep it with your Medicare papers. When you apply for Medigap, the insurer will want to see it: it's what documents your guaranteed-issue right.
And if you're the Washington member reading this: you did exactly the right thing by reading the notice the evening it posted. A plan leaving is disruptive, but the law made sure it comes with a door opening, not just one closing.