Medicare Advantage in Oakland County, Michigan
155,596 people in Oakland County, Michigan were enrolled in Medicare Advantage in October 2026, 55.5% of 280,508 eligible beneficiaries (+0.4 pts since October 2025). Blue Cross Blue Shield of Michigan Mutual Ins. Co. is the largest parent organization with 45% of reported enrollment; 17 parent organizations have 11 or more members and the HHI is 2,548 (highly concentrated). HRSA classifies the county as partly rural. For 2027, 3,051 members here are in plans that terminate or leave the county. MA plans offered go from 73 to 64.
Parent organizations in Oakland County
| Parent organization | Members | Change since October 2025 | Share |
|---|---|---|---|
| Blue Cross Blue Shield of Michigan Mutual Ins. Co. | 69,353 | −5,818 | 44.7% |
| Henry Ford Health System | 21,397 | +5,769 | 13.8% |
| Humana Inc. | 20,834 | +4,054 | 13.4% |
| CVS Health Corporation | 12,683 | +775 | 8.2% |
| Corewell Health | 12,640 | +1,284 | 8.1% |
| UnitedHealth Group, Inc. | 10,179 | −2,057 | 6.6% |
| Centene Corporation | 3,647 | −178 | 2.3% |
| Zing Health Consolidator, Inc | 2,083 | +627 | 1.3% |
| Molina Healthcare, Inc. | 1,170 | −237 | 0.8% |
| Trinity Health Corporation | 687 | +359 | 0.4% |
| Curana Health Holdings, LLC | 281 | +111 | 0.2% |
| Longevity Health Founders, LLC | 133 | +12 | under 0.1% |
| McLaren Health Care Corporation | 96 | −23 | under 0.1% |
| Elevance Health, Inc. | 85 | −7 | under 0.1% |
| Health Care Service Corporation | 17 | +3 | under 0.1% |
CMS suppresses county and contract counts of 10 or fewer; shares are of reported enrollment.
Value-based care alongside MA
In PY 2024, 39,476 beneficiaries in Oakland County were assigned to 199 Medicare Shared Savings Program ACOs, 43.0% of assignable Original Medicare beneficiaries. Together, roughly 75% of all Medicare beneficiaries in the county are in Medicare Advantage or an MSSP ACO. See the ACOs in the MSSP Explorer.