Medicare Advantage in Knox County, Maine
7,625 people in Knox County, Maine were enrolled in Medicare Advantage in October 2026, 55.9% of 13,645 eligible beneficiaries (−0.4 pts since October 2025). UnitedHealth Group, Inc. is the largest parent organization with 29% of reported enrollment; 6 parent organizations have 11 or more members and the HHI is 2,124 (highly concentrated). HRSA classifies the county as partly rural. For 2027, 2,899 members here are in plans that terminate or leave the county. MA plans offered go from 22 to 18.
Parent organizations in Knox County
| Parent organization | Members | Change since October 2025 | Share |
|---|---|---|---|
| UnitedHealth Group, Inc. | 2,220 | −16 | 29.3% |
| Martin's Point Health Care, Inc. | 1,840 | −406 | 24.3% |
| Humana Inc. | 1,550 | +779 | 20.5% |
| Elevance Health, Inc. | 945 | −271 | 12.5% |
| CVS Health Corporation | 645 | −60 | 8.5% |
| Centene Corporation | 366 | +45 | 4.8% |
CMS suppresses county and contract counts of 10 or fewer; shares are of reported enrollment.
Value-based care alongside MA
In PY 2024, 3,520 beneficiaries in Knox County were assigned to 64 Medicare Shared Savings Program ACOs, 85.2% of assignable Original Medicare beneficiaries. Together, roughly 93% of all Medicare beneficiaries in the county are in Medicare Advantage or an MSSP ACO. See the ACOs in the MSSP Explorer.