A Medicare Advantage plan that leaves the Medicare program entirely triggers one of the stronger consumer protections built into Medigap: a right to buy certain Medicare Supplement policies with no health questions asked. Medicare.gov sets that window at 60 days before the old coverage ends through 63 days after it ends. Miss both ends of it, and an insurer generally gets to ask about health history before selling a policy at all. The rule exists because losing that coverage was not a choice, unlike ordinary shopping for a policy.
What the 60-and-63-day window doesn’t decide: The window secures Medigap without health questions, not whether a different Medicare Advantage plan would fit the same drugs and doctors for less. The 2027 Medicare Open Enrollment Decision Kit runs that comparison. Compare Medicare Advantage alternatives on cost and doctors →
The 60-Day-Before, 63-Day-After Window
Medicare’s page on when to buy a Medigap policy states that a Medicare Advantage Plan leaving Medicare gives a member the right to buy Medigap Plan A, B, C, D, F, G, K or L without medical underwriting. The application has to go in no earlier than 60 days before the old coverage ends and no more than 63 days after it ends, and inside that window an insurer cannot turn an applicant down or charge more because of a medical history. Outside those dates, the same eight letters are still for sale, just without the protection against being turned away.
Two Roads Into the Same Right
A plan leaving Medicare is not the only path to this protection. Medicare’s guidance describes a second trigger: someone who joined a Medicare Advantage plan the moment they first became eligible for Medicare, and then leaves that plan within the first year, also qualifies for the same no-underwriting purchase on the same list of Medigap letters. The two triggers lead to an identical outcome at the insurance counter, but they start the clock differently, since one runs off a plan’s exit date and the other off a one-year anniversary of first joining. Which trigger applies determines which 60-and-63-day window is actually running for a given household.
The Date That Starts Both Clocks
Both the 60-day lookback and the 63-day forward count run from the same anchor point: the date the old Medicare Advantage coverage actually ends, as the plan and Medicare record it, not the date a letter announcing the change was mailed or opened. A member can apply for a Medigap policy before that end date arrives, as soon as the 60-day mark is reached, rather than waiting for coverage to lapse first. Getting that single date right matters more than anything else in the process, since an application filed even a day outside either edge of the window falls back to ordinary underwriting rules.
A Different Clock Than Turning 65
This right is separate from the standard Medigap entry point most people use. Medicare’s guide to buying a Medigap policy explains that the general Medigap open enrollment period is six months long and starts the day Part B coverage begins, not the day a plan leaves the market, and that Medigap plans themselves are standardized and identified by letter, such as Plan G or Plan K, so the same letter buys the same benefits regardless of which company sells it. Someone whose Medicare Advantage plan leaves Medicare years after that original six-month window has already closed still gets a fresh opening, because the plan’s exit resets the clock on its own terms rather than relying on the original Part B start date.
The Extra 12 Months in Some Cases
Medicare’s guidance also notes that in certain circumstances these purchase rights can extend up to 12 additional months beyond the standard 63-day tail, though which circumstances qualify depends on the specific coverage history Medicare and the plan have on file for a given person. That extension does not change the headline window itself, which remains 60 days before to 63 days after coverage ends for the ordinary case, but it means the protection does not necessarily disappear the moment day 63 passes for everyone. It also means two people who lost the same kind of coverage in the same month can end up on different underwriting terms a year later, depending on details recorded well before either of them started shopping for a replacement policy.
Underwriting Outside the Window
Waiting past day 63 carries a real cost. Medicare’s page on changing a Medigap policy says that outside an open enrollment period or one of these specific triggers, applicants generally have no federal right to buy or switch a Medigap policy, and an insurer can require medical underwriting or make someone wait out a pre-existing condition period if the current policy has been held for less than six months. Outside a protected window, the same eight plan letters remain on the market, but an insurer is free to charge more, add conditions or turn an applicant away based on health history, which is precisely the outcome the 60-and-63-day window is built to prevent. That protection sits alongside the switch rights described on Medicare’s Special Enrollment Periods page for moving to a different Medicare Advantage or Part D plan when one leaves Medicare, which runs on its own separate calendar rather than the 60-and-63-day Medigap clock described here.
Comparing the Alternative to Medigap
The 60-day-before-to-63-day-after window settles whether an insurer has to sell a Medigap policy without health questions, but it says nothing about whether Medigap or a different Medicare Advantage plan fits a specific mix of drugs and doctors better. Both paths stay open during the same stretch of weeks, and only one of them tends to get compared line by line before a decision has to be made.
The 2027 Medicare Open Enrollment Decision Kit lines up a prescription-by-plan comparison against a cost calculator spreadsheet, so a replacement Medicare Advantage plan can be weighed on the same terms as a Medigap premium before that window closes.
See how a replacement Medicare Advantage plan stacks up in The 2027 Medicare Open Enrollment Decision Kit.
This article was written with AI assistance and checked by a human editor before it was published.
