October 2, 2026 was the date by which Medicare Advantage insurers had to notify members whose plans end after December 31. A federal rule sets the deadline at 90 calendar days before a non-renewal takes effect, and it falls 13 days before Open Enrollment opens on October 15. Whether a letter has reached the mailbox is something a member can find out now.
The October 2 plan-ending notice: the letter starts clocks it does not spell out, and The 2027 Medicare Open Enrollment Decision Kit has Medigap guaranteed-issue rights with a call script and the Open Enrollment calendar.
Open the Medigap call script and Open Enrollment calendar for a plan-ending notice →
Where October 2 comes from: 90 days before a December 31 contract end
The rule is 42 CFR 422.506, which governs when a Medicare Advantage organization stops offering a plan. It requires the organization to notify “each Medicare enrollee by mail at least 90 calendar days before the date on which the nonrenewal is effective,” as the Code of Federal Regulations text puts it. For a contract that ends on December 31, counting back 90 days lands on October 2.
CMS applied the same arithmetic in earlier years. Its contract year 2021 guidance on non-renewals and service area reductions told insurers that notice “must be provided not later than October 2, 2020” for contracts ending December 31, 2020, or “at least 90 days before the end of the current contract period.” For 2026, Healthcare Finance News reported in a September 1 article by reporter Eve Bender that “federal regulations require nonrenewal notices for most Medicare Advantage contracts ending Dec. 31 to be dated Oct. 2.”
The word that matters in that sentence is “dated.” The deadline attaches to the notice, not to the day it arrives, so a letter dated October 2 can still be in the mail days later.
What the notice has to tell a member
The same CMS guidance spells out what a non-renewal notice must carry. It says insurers must tell enrollees that they “have guarantee issue rights to elect a Medigap policy if they are disenrolled from an MAO that is non-renewing or reducing its service area.” The regulation adds that the insurer must either provide a CMS-approved written description of the alternative Medicare Advantage, Medicare Advantage drug and standalone drug plan options in the member’s region, or place outbound calls to all affected enrollees so they know whom to contact about their options.
That is a federal floor, and it governs contracts that are ending. It means the October 2 notice is a legal document with required content, not a courtesy mailing, and it is the member’s first official word that the plan will not exist in 2027.
Blue Cross Minnesota and Humana show how large the mailing is
The scale shows up in the insurers’ own statements. Blue Cross and Blue Shield of Minnesota announced on October 1, 2026 that all of its current Medicare Advantage plans will be discontinued at year-end, with new Medicare Advantage products launching January 1, 2027. President and CEO Dana Erickson said, “As a non-profit health plan, Blue Cross has a responsibility to act in the interest of being able to serve all members for years to come.” The company said more than 80 percent of its current Medicare Advantage members will have new Blue Cross options and that affected members will receive personalized letters, email, text and phone communications.
The Healthcare Finance News report said about 600,000 Humana Medicare Advantage members were expected to receive exit notices. Both announcements describe insurers acting under the same rule on the same date.
An ending plan, a continuing plan and the letter each one produces
Blue Cross Minnesota’s announcement separates two kinds of mail. Members of discontinued plans get the non-renewal communication, while members of plans that continue get an Annual Notice of Change document, which lays out next year’s benefits and costs. The two are different pieces of mail with different jobs, and the October 2 deadline governs only the first.
The sources read do not say what a missing non-renewal letter means by itself. A letter dated October 2 may not have been delivered yet, and a plan that continues sends no non-renewal letter at all. What the regulation does establish is that a member of a contract that is ending is entitled to written notice by mail, so a member who expected a letter and has none by early October has a concrete question for the plan’s member services line. The answer to that call, whether the plan is ending, changing or continuing, decides which of the next steps applies.
Three clocks start from one letter, and a missing letter starts none of them on paper
Each route a member can take runs on a different calendar. The Blue Cross Minnesota announcement sets the Open Enrollment window for 2027 plans at October 15 to December 7, 2026. Separately, Medicare.gov describes the special enrollment period for a plan that ends its contract as opening two months ahead of the contract’s end date and closing one full month after it, and warns that a member who does not join another Medicare Advantage plan before the current one ends is enrolled in Original Medicare.
The third clock belongs to Medigap. In Medicare’s guide to Medigap health insurance, the guaranteed-issue right opens 60 days ahead of the Medicare Advantage coverage ending, or on the date given in the plan’s termination notice, and closes 63 days after that coverage is gone. Whichever of Plans A, B, C, D, F and G a company sells in the member’s state is on the table, though people new to Medicare after January 1, 2020 face limits on C and F. Policies sold after 2005 carry no prescription drug coverage, the guide adds, so a member taking this route has to pair one with a separate Part D plan.
The official route needs no paid help. Medicare’s 1-800-MEDICARE line, 1-800-633-4227, and the plan’s own member services number on the insurance card are the places to confirm whether a plan is ending, and the notice itself is the document that sets the member’s dates.
A letter that has not come and a Medigap window that is already counting
The October 2 non-renewal deadline sets a Medigap guaranteed-issue window and the October 15 to December 7 Open Enrollment period running on separate clocks, and a letter that has not arrived leaves a member unsure which clock applies. The costly gap is the phone call to the plan or to a Medigap insurer, made without the right dates in hand.
The 2027 Medicare Open Enrollment Decision Kit is a 42-page decision kit with Medigap guaranteed-issue rights and a call script, a provider call script and the Open Enrollment calendar.
Get The 2027 Medicare Open Enrollment Decision Kit before the windows overlap →
This piece was drafted with AI assistance; the deadline and notice rules were checked against 42 CFR 422.506, CMS non-renewal guidance, Medicare.gov and Blue Cross and Blue Shield of Minnesota’s announcement.
