Medicare Advantage in Madison County, Idaho
1,318 people in Madison County, Idaho were enrolled in Medicare Advantage in October 2026, 33.3% of 3,960 eligible beneficiaries (−14.6 pts since October 2025). UnitedHealth Group, Inc. is the largest parent organization with 60% of reported enrollment; 6 parent organizations have 11 or more members and the HHI is 4,325 (highly concentrated). HRSA classifies the county as fully rural. For 2027, 128 members here are in plans that terminate or leave the county. MA plans offered go from 8 to 7.
Parent organizations in Madison County
| Parent organization | Members | Change since October 2025 | Share |
|---|---|---|---|
| UnitedHealth Group, Inc. | 780 | +263 | 59.7% |
| Gemstone Holdings, Inc. | 325 | −798 | 24.9% |
| Molina Healthcare, Inc. | 151 | −18 | 11.6% |
| Fenyx Health Holdings, Inc. | 18 | new | 1.4% |
| Humana Inc. | 18 | new | 1.4% |
| CVS Health Corporation | 14 | 0 | 1.1% |
CMS suppresses county and contract counts of 10 or fewer; shares are of reported enrollment.
Value-based care alongside MA
In PY 2024, 1,083 beneficiaries in Madison County were assigned to 20 Medicare Shared Savings Program ACOs, 70.9% of assignable Original Medicare beneficiaries. Together, roughly 81% of all Medicare beneficiaries in the county are in Medicare Advantage or an MSSP ACO. See the ACOs in the MSSP Explorer.