Medicare Advantage in Waukesha County, Wisconsin
63,760 people in Waukesha County, Wisconsin were enrolled in Medicare Advantage in October 2026, 59.5% of 107,159 eligible beneficiaries (−0.4 pts since October 2025). UnitedHealth Group, Inc. is the largest parent organization with 59% of reported enrollment; 10 parent organizations have 11 or more members and the HHI is 3,942 (highly concentrated). For 2027, 2,135 members here are in plans that terminate or leave the county, and Sanford Health leaves. MA plans offered go from 39 to 33.
Parent organizations in Waukesha County
| Parent organization | Members | Change since October 2025 | Share |
|---|---|---|---|
| UnitedHealth Group, Inc. | 37,390 | −2,213 | 58.7% |
| Network Health, Inc. | 10,338 | +4,943 | 16.2% |
| Humana Inc. | 8,213 | +1,226 | 12.9% |
| CVS Health Corporation | 4,378 | +182 | 6.9% |
| Elevance Health, Inc. | 2,383 | −1,301 | 3.7% |
| Centene Corporation | 506 | +233 | 0.8% |
| CareSource | 149 | −16 | 0.2% |
| Sanford Health | 136 | +38 | 0.2% |
| Molina Healthcare, Inc. | 121 | +31 | 0.2% |
| Blue Cross Blue Shield of Michigan Mutual Ins. Co. | 45 | +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, 24,863 beneficiaries in Waukesha County were assigned to 105 Medicare Shared Savings Program ACOs, 78.7% of assignable Original Medicare beneficiaries. Together, roughly 91% of all Medicare beneficiaries in the county are in Medicare Advantage or an MSSP ACO. See the ACOs in the MSSP Explorer.