Medicare Advantage in San Joaquin County, California
72,279 people in San Joaquin County, California were enrolled in Medicare Advantage in October 2026, 55.5% of 130,330 eligible beneficiaries (+0.6 pts since October 2025). Kaiser Foundation Health Plan, Inc. is the largest parent organization with 48% of reported enrollment; 16 parent organizations have 11 or more members and the HHI is 2,757 (highly concentrated). HRSA classifies the county as partly rural. For 2027, 3,344 members here are in plans that terminate or leave the county, and Molina Healthcare, Inc., SANTA CLARA COUNTY HEALTH AUTHORITY leave. MA plans offered go from 25 to 22.
Parent organizations in San Joaquin County
| Parent organization | Members | Change since October 2025 | Share |
|---|---|---|---|
| Kaiser Foundation Health Plan, Inc. | 34,959 | +1,703 | 48.5% |
| Alignment Healthcare USA, LLC | 10,172 | +1,297 | 14.1% |
| Humana Inc. | 6,885 | −554 | 9.5% |
| SCAN Group | 5,126 | +5,110 | 7.1% |
| Centene Corporation | 3,190 | −305 | 4.4% |
| Imperial Health Plan of California | 3,162 | +867 | 4.4% |
| UnitedHealth Group, Inc. | 2,642 | −1,348 | 3.7% |
| Elevance Health, Inc. | 1,627 | −410 | 2.3% |
| Molina Healthcare, Inc. | 1,508 | −1,978 | 2.1% |
| California Physicians' Service | 1,226 | −1,329 | 1.7% |
| WelbeHealth LLC. | 731 | +91 | 1.0% |
| CVS Health Corporation | 662 | −727 | 0.9% |
| SAN JOAQUIN COUNTY HEALTH COMMISSION | 193 | new | 0.3% |
| SANTA CLARA COUNTY HEALTH AUTHORITY | 12 | −1 | under 0.1% |
| Golden Valley Health Centers | 11 | new | 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, 19,605 beneficiaries in San Joaquin County were assigned to 96 Medicare Shared Savings Program ACOs, 53.5% of assignable Original Medicare beneficiaries. Together, roughly 79% of all Medicare beneficiaries in the county are in Medicare Advantage or an MSSP ACO. See the ACOs in the MSSP Explorer.