If you live in Michigan and you have been searching for how and when to change your Medicare Advantage or Medigap plan, you have probably found confusing answers, because the rules depend on which type of plan you have. Here is a clear Michigan-specific guide that separates the two, with the federal windows that apply everywhere and what to check for Michigan in particular.
The quick answer for Michigan
- Medicare Advantage: you can generally change during the Annual Enrollment Period (October 15 to December 7), during the Medicare Advantage Open Enrollment Period (January 1 to March 31) if you are already in an Advantage plan, or during a Special Enrollment Period if you qualify. These windows are set by Medicare, so they are the same in Michigan as in every state.
- Medigap: there is no annual deadline, but whether you can switch without health questions depends on protections that include some state rules. See below for what we found for Michigan.
Medicare Advantage changes in Michigan
- Annual Enrollment Period (Oct 15 – Dec 7). Change plans for the following January 1. See our Annual Enrollment guide.
- Medicare Advantage Open Enrollment (Jan 1 – Mar 31). If you are already in an Advantage plan, you get one change. Read the full guide.
- Special Enrollment Periods. Triggered by moving to a new area, losing other coverage, your plan ending, or qualifying for Extra Help or Medicaid, among others. See when you can switch plans.
Medigap changes in Michigan
In the recent 2026 sources we reviewed, Michigan was not listed as having a Medigap birthday rule, though one source notes that similar legislation has been considered. That generally means that outside your Medigap Open Enrollment Period and federal guaranteed-issue situations, an insurer may ask health questions when you apply to change plans. Rules can change, so confirm with DIFS, and do not cancel your current plan until a new one is approved.
Regardless of state, you generally have protection in your six-month Medigap Open Enrollment Period and in certain federal guaranteed-issue situations. Our national guide, when can I change my Medigap plan, explains each one.
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Get my plan reviewWhat to think about in Michigan
Michigan has a big difference between the Detroit, Ann Arbor, and Grand Rapids health systems and the northern Lower Peninsula and Upper Peninsula, where networks are smaller and travel for specialty care can be long. Many Michiganders also spend winters elsewhere, so ask how a plan covers care outside its service area. Plan availability varies by county, so compare options at your exact address. We serve people in and around Detroit, Grand Rapids, Lansing, Ann Arbor, Flint and the Upper Peninsula, and we handle everything by phone.
Common situations people ask about
- "My doctor left my plan's network." You may qualify for a Special Enrollment Period in some cases, and you can compare plans at the next window. See what to do when a plan drops your doctor.
- "My premium or drug costs went up." Review your Annual Notice of Change and compare during the next open window.
- "I moved within Michigan." A move to a different county can change which plans you can choose, and may open a Special Enrollment Period.
- "I want to move from Advantage back to Original Medicare." Check your Medigap options before you cancel. Read leaving Medicare Advantage.
- "I have both Medicare and Medicaid." You may have more frequent change opportunities. See Medicaid and dual-eligible options.
- "I winter in another state." Ask how the plan covers care outside Michigan, and whether it limits non-emergency care away from home.
A checklist before you change anything in Michigan
- Identify which window you are in (AEP, MA-OEP, SEP, or Medigap rules).
- List your doctors, hospitals, pharmacies, and medications.
- Check each against the plan you are considering at your Michigan address.
- If it is Medigap, find out whether underwriting applies and apply before you cancel.
- Confirm the effective date in writing.
How Honorbrook helps Michigan residents
We are an independent agency licensed in Michigan and 10 other states. We compare plans offered at your address across many carriers, check your doctors and drugs, and explain the trade-offs plainly. Our help is free because carriers pay us, and your premium is the same whether you use an agent or enroll yourself. See our Michigan Medicare page for more about how we work in your state.
Medicare Advantage by county in Michigan
Medicare plan choices are set county by county. Statewide, about 63.6% of people with Medicare in Michigan are enrolled in a Medicare Advantage plan (CMS, September 2026). Here are the 10 largest counties by residents age 65 and older:
| County | Residents 65+ | Medicare Advantage share |
|---|---|---|
| Wayne County | 299,646 | 64.9% |
| Oakland County | 242,408 | 55.5% |
| Macomb County | 164,492 | 60.3% |
| Kent County | 102,130 | 74.5% |
| Genesee County | 77,829 | 69.7% |
| Washtenaw County | 60,189 | 59.4% |
| Ottawa County | 52,010 | 77.3% |
| Kalamazoo County | 43,432 | 65.8% |
| Ingham County | 43,269 | 67.1% |
| Livingston County | 40,325 | 55.1% |
Questions about your options? Fill out our short form and a licensed agent will reach out. See every county on our Michigan county directory or our Michigan Medicare hub. Sources: U.S. Census Bureau 2023 estimates; CMS Medicare Advantage State/County Penetration.
Changing Medicare plans in other states
We are licensed in 11 states. The enrollment windows are federal and the same everywhere, but plan choices and free local help are state-specific:
- When can I change my Medicare plan in Virginia?
- When can I change my Medicare plan in Maryland?
- When can I change my Medicare plan in North Carolina?
- When can I change my Medicare plan in South Carolina?
- When can I change my Medicare plan in Georgia?
- When can I change my Medicare plan in Alabama?
- When can I change my Medicare plan in Louisiana?
- When can I change my Medicare plan in Texas?
- When can I change my Medicare plan in Indiana?
- When can I change my Medicare plan in West Virginia?