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Top MA Enrollment Contracts in Washington (Jul 2026)
This page summarizes county-level Medicare Advantage enrollment by contract in Washington.
Home / Data Tools / MA Enrollment / MA State Rankings / Washington
Data source: SCC Enrollment MA Alternative File (2026-07). State total enrollment shown: 786,660.
Top 10 Contracts
| Rank | Contract ID | Organization Name | Plan Type | Enrolled | Counties | State Share |
|---|---|---|---|---|---|---|
| 1 | H3805 | UnitedHealthcare Benefits of Texas, Inc. | HMO/HMOPOS | 191,184 | 20 | 24.3% |
| 2 | H2001 | SIERRA HEALTH AND LIFE INSURANCE COMPANY, INC. | Local PPO | 108,327 | 39 | 13.8% |
| 3 | H5050 | KAISER FOUNDATION HEALTH PLAN OF WASHINGTON | HMO/HMOPOS | 98,922 | 12 | 12.6% |
| 4 | H5619 | ARCADIAN HEALTH PLAN, INC. | HMO/HMOPOS | 61,600 | 33 | 7.8% |
| 5 | H5008 | CARE IMPROVEMENT PLUS SOUTH CENTRAL INSURANCE CO. | HMO/HMOPOS | 37,174 | 30 | 4.7% |
| 6 | H5216 | HUMANA INSURANCE COMPANY | Local PPO | 34,041 | 38 | 4.3% |
| 7 | H0029 | COORDINATED CARE OF WASHINGTON, INC. | HMO/HMOPOS | 31,800 | 35 | 4.0% |
| 8 | H1036 | HUMANA MEDICAL PLAN, INC. | HMO/HMOPOS | 30,483 | 30 | 3.9% |
| 9 | H9003 | KAISER FOUNDATION HP OF THE N W | HMO/HMOPOS | 30,015 | 5 | 3.8% |
| 10 | H5521 | AETNA LIFE INSURANCE COMPANY | Local PPO | 27,038 | 7 | 3.4% |
Method note: Enrollment is based on legal state/county of residence for payment purposes and may include out-of-service-area beneficiaries.
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