Medicare Advantage in Island County, Washington
11,365 people in Island County, Washington were enrolled in Medicare Advantage in October 2026, 41.5% of 27,367 eligible beneficiaries (−0.1 pts since October 2025). UnitedHealth Group, Inc. is the largest parent organization with 60% of reported enrollment; 12 parent organizations have 11 or more members and the HHI is 4,295 (highly concentrated). HRSA classifies the county as partly rural. For 2027, 5,010 members here are in plans that terminate or leave the county, and Kaiser Foundation Health Plan, Inc. leaves. MA plans offered go from 21 to 12.
Parent organizations in Island County
| Parent organization | Members | Change since October 2025 | Share |
|---|---|---|---|
| UnitedHealth Group, Inc. | 6,834 | +258 | 60.4% |
| Kaiser Foundation Health Plan, Inc. | 2,624 | −157 | 23.2% |
| Humana Inc. | 1,025 | −17 | 9.1% |
| CVS Health Corporation | 542 | +22 | 4.8% |
| Elevance Health, Inc. | 86 | +1 | 0.8% |
| Centene Corporation | 81 | +2 | 0.7% |
| Molina Healthcare, Inc. | 25 | −3 | 0.2% |
| Cambia Health Solutions, Inc. | 24 | −3 | 0.2% |
| Community Health Plan of Washington | 21 | +8 | 0.2% |
| California Physicians' Service | 19 | 0 | 0.2% |
| Health Care Service Corporation | 16 | −1 | 0.1% |
| Blue Cross Blue Shield of Michigan Mutual Ins. Co. | 14 | new | 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, 7,000 beneficiaries in Island County were assigned to 82 Medicare Shared Savings Program ACOs, 59.9% of assignable Original Medicare beneficiaries. Together, roughly 77% of all Medicare beneficiaries in the county are in Medicare Advantage or an MSSP ACO. See the ACOs in the MSSP Explorer.