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Vlada / Medicare Advantage / Michigan / St. Clair County

Medicare Advantage plan exits 2027 in St. Clair County, MI

353 of the 16,995 Medicare Advantage members in St. Clair County (2.1%) are in a plan that is not sold in the county for 2027: 6 of the 69 plans sold there in September 2026 end, from the CMS 2027 Landscape and crosswalk. Michigan: 9.9%; the nation: 10.6%.

Period: plan year 2027 against September 2026 members · Updated 2026-10-20 · Next: CMS January 2027 enrollment (February 2027): where the members landed

members, Sept 2026
16,995
members, Sept 2026
must pick for 2027
353
must pick for 2027
share of members
2.1%
share of members
plans end
6 of 69
plans end

Medicare Advantage members in St. Clair County, 2015 to 2026

MA enrollment in September each year, with MA penetration (members over Medicare eligibles) at the top of each bar, from the CMS state-county penetration file. Navy: the last two years. 64 plans are listed for the county for 2027 against 74 for 2026.

07k14k20k27k31%201532%35%201737%40%201946%50%202154%58%202361%63%202563%

The plans that end for 2027

Every plan sold in St. Clair County in September 2026 with members whose plan is not sold there for 2027: how it went (terminated, or its service area reduced so it continues elsewhere), the members the same company offers a new or renumbered plan of the same type, and the members whose company sells nothing in the county next year.

PlanCompanyTypeMembersTerminatedService area reducedOffered a new or renumbered planCompany gone
Prioritymedicare Vital (PPO) H4875-022Corewell HealthRegular PPO177177000
Wellcare Dual Access Open (PPO D-SNP) H2117-002Centene CorporationD-SNP PPO7979000
Wellcare Simple Open (PPO) H2117-001Centene CorporationRegular PPO4444000
Humana Gold Plus Chronic Kidney Disease (HMO C-SNP) H8908-006Humana Inc.CSNP HMO2121000
Wellcare Patriot Giveback Open (PPO) H2117-003Centene CorporationRegular PPO1919000
Prioritymedicare Vintage (HMO-POS) H2320-031Corewell HealthRegular HMO13130130
6 plans3533530130

Download this table (CSV, CC BY 4.0) · cells under 11 members are suppressed by CMS and count as zero, so every count is a floor.

By company in St. Clair County

CompanyMembers, Sept 2026PlansPlans endingMust pickShare of own membersOffered a new or renumbered planCompany gone
Corewell Health1,56311219012.2%130
Centene Corporation4137314234.4%00
Humana Inc.5,564181210.4%00
Blue Cross Blue Shield of Michigan Mutual Ins. Co.3,92012000.0%00
Henry Ford Health System3,29410000.0%00
CVS Health Corporation2,1257000.0%00
McLaren Health Care Corporation712000.0%00
Longevity Health Founders, LLC251000.0%00
Molina Healthcare, Inc.201000.0%00

St. Clair County against Michigan and the nation

MeasureCountyMichiganUnited States
Must pick for 2027, share of members2.1%9.9%10.6%
Must pick for 20262.1%10.1%
Must pick for 2025, members179 of 14,664
Must pick for 2026, members337 of 15,984
Must pick for 2027, members353 of 16,995

State and national figures: the Michigan hub and the national report.

Star Ratings 2027 in St. Clair County

Measure20272026Change
Members in contracts rated 4+ stars81.4%73.2%+8.2 pts
Member-weighted average star4.174.13+0.04
Rated contracts with members here1919

Members by star, 2027: 5.0: 25 · 4.5: 14,236 · 4.0: 7,550 · 3.5: 4,627 · 3.0: 342; 142 in unrated contracts. Each contract's 2027 overall star (CMS, released 2026-10-08) weighted by its 2026-09 members in the county, individual and group; 2026 by 2025-09 members.

Sources

  • CMS Medicare Advantage/Part D Landscape, plan year 2027: landscape_cy2027-landscape-202609-1.zip (CMS, September 2026); CMS plan crosswalk CY2027.
  • CMS monthly enrollment by contract, plan and county, 2026-09 (and the two Septembers before, for the series).
  • CMS MA state-county penetration file, September of each year (eligibles, enrollment, penetration).
  • CMS Star Ratings 2027, released 2026-10-08. Page object written 2026-10-20.

Receipts: athena(table=medicare_semantic.exits_cells_county_2027_v1, block=plans) 042eb472aa7d…; athena(table=medicare_semantic.exits_cells_county_2025_v1, medicare_semantic.exits_cells_county_2026_v1, medicare_semantic.exits_cells_county_2027_v1, block=series) ee9fd56a8632…; athena(table=medicare_semantic.ma_spine_county_market_v20261012b, block=market) e6c1b5ce62c0…; athena(table=medicare_semantic.ma_spine_contract_stars_v20261012b, weights=medicare_semantic.ma_spine_enroll_plan_county_v20261012a, block=stars) c39711c388e0…. Suppressed cells count as zero in every count.

Cite: Vlada Health (2026). Medicare Advantage plan exits 2027 in St. Clair County, MI. https://www.vladahealth.com/medicare-advantage/mi/st-clair. Data: CC BY 4.0.

Method

  • Population: members of individual Medicare Advantage plans (H and R contracts, plans 001 to 799, special needs plans included; employer group, Cost, MMP and PACE excluded) in the county in September 2026.
  • Must pick: the CMS crosswalk names no successor plan sold in the county for 2027; members CMS moves to a successor in the county are not counted.
  • Terminated: the plan is gone from every county. Service area reduced: the plan continues elsewhere but not here. Offered a new or renumbered plan: the same company sells, in this county, the same name under a new number or a new plan of the same HMO or PPO and special needs type. Company gone: no plan of any type from that company in the county.
  • Stars: each contract's overall star weighted by its September members in the county; unrated contracts counted apart, never as zero stars. Penetration: the CMS file's own eligibles and MA enrollment.
  • Suppression: CMS hides cells under 11 members; they count as zero, so every count is a floor and every share is not.

The full method and the national tables: How we counted, and how to check it.

Questions

How many Medicare Advantage members in St. Clair County must pick a new plan for 2027?
353 of 16,995 members (2.1%): their plan is not sold in the county for 2027 according to the CMS crosswalk and Landscape. Michigan as a whole: 9.9%; the nation: 10.6%.
Which plan in St. Clair County ends with the most members?
Prioritymedicare Vital (PPO) (H4875-022, Corewell Health): 177 members in September 2026, terminated.
Which company ended the most plans in St. Clair County for 2027?
Corewell Health: 190 of its 1,563 members in the county (12.2%), 2 of its 11 plans.
What share of St. Clair County's Medicare eligibles are in Medicare Advantage?
63.4% in September 2026: 27,208 of 42,891 eligibles, from the CMS state-county penetration file.
How are St. Clair County's members rated for 2027?
81.4% of members are in contracts rated 4 stars or more for 2027 (73.2% the year before); the member-weighted average star is 4.17 over 19 rated contracts.
How does 2027 compare with 2026 in St. Clair County?
337 members (2.1%) had to pick a new plan for 2026; for 2027 it is 353 (2.1%), a change of +16 members.

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Use Vlada. In St. Clair County, Michigan, which Medicare Advantage plans are not sold for 2027, how many members are in each, and what did 2026 look like? Give me a table with the source file, the data vintage and the response hash.

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