2027 open enrollment. 3.15M must pick a new plan.

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Vlada / Medicare Advantage / Illinois / Cook County

Medicare Advantage plan exits 2027 in Cook County, IL

12,274 of the 327,012 Medicare Advantage members in Cook County (3.8%) are in a plan that is not sold in the county for 2027: 9 of the 75 plans sold there in September 2026 end, from the CMS 2027 Landscape and crosswalk. Illinois: 7.7%; 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
327,012
members, Sept 2026
must pick for 2027
12,274
must pick for 2027
share of members
3.8%
share of members
plans end
9 of 75
plans end

Medicare Advantage members in Cook 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. 67 plans are listed for the county for 2027 against 78 for 2026.

0101k201k302k402k22%201523%26%201728%30%201933%37%202140%42%202344%45%202545%

The plans that end for 2027

Every plan sold in Cook 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
Blue Cross Medicare Advantage Choice Plus (PPO) H8634-003Health Care Service CorporationRegular PPO4,0944,094000
Humana Full Access H5216-412 (PPO) H5216-412Humana Inc.Regular PPO2,4482,448000
Blue Cross Medicare Advantage Choice Premier (PPO) H8634-004Health Care Service CorporationRegular PPO1,7631,763000
Blue Cross Medicare Advantage Basic Plus (HMO-POS) H3822-007Health Care Service CorporationRegular HMO1,5031,503000
Humana Full Access H7617-009 (PPO) H7617-009Humana Inc.Regular PPO1,0441,044000
Blue Cross Medicare Advantage Secure (HMO) H8547-001Health Care Service CorporationRegular HMO900900000
Blue Cross Medicare Advantage Premier Plus (HMO-POS) H3822-008Health Care Service CorporationRegular HMO353353000
Molina Medicare Choice Care (HMO) H2715-003Molina Healthcare, Inc.Regular HMO102102000
Wellcare Patriot Giveback (HMO) H5779-011Centene CorporationRegular HMO67670670
9 plans12,27412,2740670

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 Cook County

CompanyMembers, Sept 2026PlansPlans endingMust pickShare of own membersOffered a new or renumbered planCompany gone
Health Care Service Corporation31,1191158,61327.7%00
Humana Inc.134,9691623,4922.6%00
Molina Healthcare, Inc.3,999211022.6%00
Centene Corporation25,32181670.3%670
UnitedHealth Group, Inc.58,74510000.0%00
CVS Health Corporation48,4879000.0%00
Zing Health Consolidator, Inc14,2057000.0%00
Devoted Health, Inc.6,5496000.0%00
Lumeris Group Holdings Corporation2,1434000.0%00
Longevity Health Founders, LLC7651000.0%00
Rifkin Managed Care Holding, LLC7101000.0%00

Cook County against Illinois and the nation

MeasureCountyIllinoisUnited States
Must pick for 2027, share of members3.8%7.7%10.6%
Must pick for 20264.3%10.1%
Must pick for 2025, members6,239 of 271,242
Must pick for 2026, members12,245 of 285,674
Must pick for 2027, members12,274 of 327,012

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

Star Ratings 2027 in Cook County

Measure20272026Change
Members in contracts rated 4+ stars76.3%35.9%+40.4 pts
Member-weighted average star3.973.74+0.23
Rated contracts with members here3435

Members by star, 2027: 5.0: 1,309 · 4.5: 94,192 · 4.0: 178,819 · 3.5: 52,065 · 3.0: 33,218 · 2.5: 29; 39,627 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 Cook County, IL. https://www.vladahealth.com/medicare-advantage/il/cook. 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 Cook County must pick a new plan for 2027?
12,274 of 327,012 members (3.8%): their plan is not sold in the county for 2027 according to the CMS crosswalk and Landscape. Illinois as a whole: 7.7%; the nation: 10.6%.
Which plan in Cook County ends with the most members?
Blue Cross Medicare Advantage Choice Plus (PPO) (H8634-003, Health Care Service Corporation): 4,094 members in September 2026, terminated.
Which company ended the most plans in Cook County for 2027?
Health Care Service Corporation: 8,613 of its 31,119 members in the county (27.7%), 5 of its 11 plans.
What share of Cook County's Medicare eligibles are in Medicare Advantage?
44.8% in September 2026: 402,008 of 896,718 eligibles, from the CMS state-county penetration file.
How are Cook County's members rated for 2027?
76.3% of members are in contracts rated 4 stars or more for 2027 (35.9% the year before); the member-weighted average star is 3.97 over 34 rated contracts.
How does 2027 compare with 2026 in Cook County?
12,245 members (4.3%) had to pick a new plan for 2026; for 2027 it is 12,274 (3.8%), a change of +29 members.

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