It starts before the leaves have finished turning. A plan notice. A new premium. A postcard with a smiling couple on a dock. Another envelope stamped IMPORTANT in red, just like the last three.
By the middle of October, there’s a pile on the kitchen table.
If you have Medicare, the hard part usually isn’t reading the mail. It’s knowing which envelope to open first, and which dates actually apply to you.
That second part trips up a lot of people, because Medicare doesn’t run on one calendar. It runs on at least three. The fall dates everyone talks about are only one of them. If you have a Medicare Supplement policy, or you want one, the dates that matter most may be somewhere else entirely.
Black Insurance Group, LLC offers Medicare Supplement insurance guidance to families in Marceline and across Missouri. Here’s how the three calendars fit together.
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Calendar one
Medicare Open Enrollment
When: October 15 – December 7, 2026. Changes start January 1, 2027.
What it’s for: Changing Medicare Advantage or Part D drug plans.
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Calendar two
Your Medigap Open Enrollment
When: Six months, one time, starting the first month you’re 65 or older and enrolled in Part B. It does not restart each fall.
What it’s for: Buying a Medigap policy without being turned down or charged more because of your health history.
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Calendar three
Your Missouri anniversary window
When: 30 days before or after your Medigap policy’s anniversary.
What it’s for: Switching to the same-lettered plan with a different insurer, if you already have a Medigap policy.
Calendar one: October 15 through December 7
This is the one in all the TV commercials. Medicare’s annual Open Enrollment Period runs from October 15 through December 7, 2026. Depending on your current coverage and eligibility, you can change Medicare Advantage or Part D prescription drug plans, or switch between Original Medicare and Medicare Advantage.
If the plan receives your enrollment request by December 7, the change takes effect January 1, 2027.
You don’t have to change anything just because the season showed up. You do need to know whether your current plan is continuing and what will be different next year. A company name you recognize doesn’t tell you what next year will cost or cover.
Calendar two: your own Medigap window
Medicare Supplement insurance, also called Medigap, helps pay some of the out-of-pocket costs Original Medicare leaves behind, like deductibles, copayments, and coinsurance, depending on the policy. It generally requires Medicare Parts A and B. Medicare.gov’s Medigap basics shows how the pieces fit together.
Under federal law, your six-month Medigap Open Enrollment Period begins the first month you’re 65 or older and enrolled in Part B. During those six months, an insurer can’t deny you a Medigap policy it sells, or charge you more, because of your health history. Some pre-existing-condition waiting periods can still apply.
Here’s the part people miss. That window doesn’t come back every fall.
Once it closes, an insurer may use medical underwriting unless you have a guaranteed issue right or another protection that applies. That can affect whether you’re accepted and what you pay. Before you count on an October or November application, read Medicare’s explanation of Medigap enrollment protections.
On Medicare before 65 because of a disability? Ask about Missouri’s additional protections for eligible people. The federal age-65 rule doesn’t describe every Missouri situation.
Calendar three: your policy’s anniversary
If you already have Medicare Supplement insurance, find your policy’s anniversary date. Not your birthday. The date the policy started.
The Missouri Medigap Shopping Guide explains that policyholders can switch insurers during the 30 days before or after that anniversary. If you move to the same-lettered plan, the new insurer can’t deny you coverage or make you wait because of pre-existing conditions.
That protection is tied to an existing Medigap policy. It isn’t a general opening for everyone with Medicare Advantage to buy a supplement without health underwriting.
Ask the agent or insurer to confirm your anniversary, which replacement policies qualify, when to apply, and when the new policy would start. Keep your renewal notice or other proof of current coverage handy. If you want a different level of benefits, ask separately how the rules apply.
Before you cancel anything, make sure the replacement policy has been issued and the dates line up. Medicare also cautions that dropping a Medigap policy can affect your ability to get it back.
Open the plan notice before the postcard
If you have a Medicare Advantage or Part D plan, one envelope deserves the top of the pile: the Annual Notice of Change, usually called the ANOC. Medicare says it arrives in September and explains what changes in January. If yours is missing, contact the plan for a copy.
Pour a cup of coffee and read it against your real life:
- Prescriptions: Are your current medicines covered, and what will you pay at the pharmacy you actually use?
- Doctors and hospitals: If your plan uses a network, will the providers you rely on be in it next year?
- Total costs: What are the premiums, deductibles, and other out-of-pocket costs? The monthly premium is only one number.
- Plan changes: Is the plan continuing, and does any letter say you need to take action?
- Coverage you already have: Could a change affect employer, retiree, or other benefits?
For help comparing Medicare health and drug plans, use Medicare’s Plan Finder or Missouri SHIP, which provides free, unbiased Medicare counseling.
Keeping your supplement? Still check your drug plan.
A Medicare Supplement review and a prescription drug plan review answer different questions. Medigap policies sold after 2005 don’t include prescription drug coverage, as Medicare’s coverage guide explains.
If you have a separate Part D plan, check its 2027 information even if you’re keeping your supplement. One number has already moved: Medicare lists the out-of-pocket threshold for covered Part D drugs at $2,400 in 2027, up from $2,100 in 2026. That threshold is separate from premiums, and not every prescription purchase counts toward it. Your plan and your medicines still matter. See Medicare’s drug-cost explanation.
Bring your Medicare Supplement questions to us. For a health or drug plan comparison, the official resources above can walk you through the details.
Turning 65 or retiring soon? Your clock may be different.
New to Medicare? Start with Medicare’s sign-up questions, not the fall dates. December 7 is not the deadline for enrolling in Parts A and B.
If you or your spouse is still working, the type of employer coverage and your circumstances matter. Talk with the benefits administrator before you change anything. Medicare’s working-past-65 guidance also warns that COBRA doesn’t extend your limited time to sign up for Part B.
Have those conversations before the job or the coverage ends. Not after.
Five questions to bring to the call
You don’t need to know every insurance term before you call. Nobody does. Start with these:
- When did my Part B coverage begin, and which Medigap protections apply to me?
- If I already have a supplement, what is its plan letter and anniversary date?
- What would the available policy cover, and what would still be my responsibility?
- Would medical underwriting or a waiting period apply?
- What has to be confirmed before any existing coverage is changed?
You can reach the Marceline office by phone from anywhere in Missouri. For privacy, please don’t send Medicare numbers, medical information, or other sensitive details in an ordinary email. Call and ask how that information should be handled.
Start with one envelope
You don’t have to clear the whole pile tonight. Find one date. Get one confusing letter explained.
For Medicare Supplement questions, call Black Insurance Group, LLC at (660) 376-4200 or visit the contact page. We’re at 115 E Howell Ave in Marceline and serve customers throughout Missouri.
This article provides general educational information. Eligibility, enrollment rights, available products, and policy terms depend on your circumstances. It does not recommend a particular plan. Coverage cannot be bound, changed, or cancelled through this website.
