Medicare Advantage in Hamilton County, Iowa
919 people in Hamilton County, Iowa were enrolled in Medicare Advantage in October 2026, 25.3% of 3,632 eligible beneficiaries (−0.3 pts since October 2025). CVS Health Corporation is the largest parent organization with 30% of reported enrollment; 7 parent organizations have 11 or more members and the HHI is 2,210 (highly concentrated). HRSA classifies the county as fully rural. For 2027, 161 members here are in plans that terminate or leave the county, and Blue Cross Blue Shield of Michigan Mutual Ins. Co. leaves. MA plans offered go from 23 to 22.
Parent organizations in Hamilton County
| Parent organization | Members | Change since October 2025 | Share |
|---|---|---|---|
| CVS Health Corporation | 263 | −6 | 29.5% |
| UnitedHealth Group, Inc. | 234 | −147 | 26.2% |
| Humana Inc. | 173 | +69 | 19.4% |
| Blue Cross Blue Shield of Michigan Mutual Ins. Co. | 141 | +33 | 15.8% |
| Trinity Health Corporation | 38 | new | 4.3% |
| Centene Corporation | 29 | new | 3.2% |
| Mitchell Family Office | 15 | −4 | 1.7% |
CMS suppresses county and contract counts of 10 or fewer; shares are of reported enrollment.
Value-based care alongside MA
In PY 2024, 1,786 beneficiaries in Hamilton County were assigned to 17 Medicare Shared Savings Program ACOs, 82.2% of assignable Original Medicare beneficiaries. Together, roughly 87% of all Medicare beneficiaries in the county are in Medicare Advantage or an MSSP ACO. See the ACOs in the MSSP Explorer.