MA Enrollment Explorer / Parent organizations / Health Care Service Corporation
Health Care Service Corporation: Medicare Advantage enrollment and market share
Health Care Service Corporation had 899,839 Medicare Advantage members in October 2026, #7 nationally with 2.5% of all MA enrollment. It lost 77,923 members (−8.0%) since October 2025, and has enrollment in 47 states and 1,014 counties with 11 or more members, leading the market in 18 of them. In the 2026 Annual Election Period (December to February) it lost 97,533 members (−10.0%). For 2027, 120,878 of its members are in plans that terminate and 17,044 in plans leaving their county, and it leaves 290 counties entirely. Among members who stay, 45,345 lose a Part B giveback and 166,945 an OTC allowance.
900KMA members, October 2026
−8.0%change since October 2025 (−77,923)
2.5%national MA share, rank 7
24contracts with enrollment
Largest states
| State | Members | Share of state MA |
|---|---|---|
| Texas | 309,097 | 11.2% |
| Tennessee | 86,399 | 10.5% |
| Arizona | 77,059 | 9.6% |
| Illinois | 68,491 | 6.2% |
| Alabama | 52,485 | 7.4% |
| New Mexico | 43,042 | 17.8% |
| Pennsylvania | 36,380 | 2.2% |
| Georgia | 34,117 | 3.0% |
| North Carolina | 33,661 | 2.5% |
| Ohio | 18,846 | 1.3% |
| Florida | 17,626 | 0.6% |
| South Carolina | 16,260 | 2.7% |
| Mississippi | 14,476 | 4.9% |
| Montana | 13,764 | 17.2% |
| Maryland | 10,195 | 3.4% |
Largest counties
| County | Members | Change since October 2025 | Share of county MA |
|---|---|---|---|
| Harris County, TX | 64,806 | +1,357 | 15.8% |
| Maricopa County, AZ | 59,774 | −413 | 14.1% |
| Cook County, IL | 38,366 | −16,539 | 9.5% |
| Hidalgo County, TX | 27,862 | −3,034 | 28.2% |
| Dallas County, TX | 20,608 | +23 | 10.3% |
| Philadelphia County, PA | 20,469 | −2,116 | 12.6% |
| Davidson County, TN | 19,024 | +1,141 | 32.2% |
| Cameron County, TX | 18,498 | −2,078 | 33.3% |
| Bexar County, TX | 17,556 | +1,174 | 8.6% |
| Bernalillo County, NM | 16,326 | +385 | 19.3% |
| El Paso County, TX | 15,953 | −454 | 13.7% |
| Tarrant County, TX | 14,941 | −1,599 | 8.1% |
| Fort Bend County, TX | 11,630 | +361 | 15.1% |
| Mobile County, AL | 10,879 | +1,664 | 16.8% |
| Jefferson County, AL | 10,438 | +363 | 11.2% |
Contracts
| Contract | Plan type | Oct 2024 | Oct 2025 | Oct 2026 |
|---|---|---|---|---|
| H4513 HealthSpring | HMO/HMOPOS | 265,634 | 365,917 | 387,988 |
| H0107 Blue Cross and Blue Shield of Montana | Local PPO | 84,159 | 96,229 | 101,932 |
| H0354 HealthSpring | HMO/HMOPOS | 58,350 | 75,062 | 75,502 |
| H3949 HealthSpring | HMO/HMOPOS | 34,362 | 39,667 | 37,337 |
| H9725 HealthSpring | HMO/HMOPOS | 14,614 | 28,432 | 33,220 |
| H0439 HealthSpring | HMO/HMOPOS | 17,116 | 24,654 | 31,586 |
| H7849 HealthSpring | Local PPO | 96,436 | 85,925 | 28,900 |
| H8634 Blue Cross and Blue Shield of IL, NM, OK, TX | Local PPO | 39,832 | 31,745 | 27,203 |
| H0672 HealthSpring | HMO/HMOPOS | 10,170 | 19,157 | 26,459 |
| H3822 Blue Cross and Blue Shield of IL, NM | HMO/HMOPOS | 19,819 | 20,206 | 21,477 |
| H3251 Blue Cross and Blue Shield of New Mexico | HMO/HMOPOS | 13,722 | 20,529 | 19,978 |
| H7787 HealthSpring | Local PPO | 27,530 | 18,476 | 17,913 |
| H1666 Blue Cross and Blue Shield of NM, TX | Local PPO | 15,323 | 18,744 | 15,765 |
| H5410 HealthSpring | HMO/HMOPOS | 28,068 | 33,076 | 15,713 |
| H7020 HealthSpring | HMO/HMOPOS | 5,955 | 11,775 | 15,611 |
| H4407 HealthSpring | HMO/HMOPOS | 11,977 | 13,010 | 14,530 |
| H2108 HealthSpring | HMO/HMOPOS | 12,497 | 12,913 | 12,823 |
| H9706 Blue Cross and Blue Shield of Texas | HMO/HMOPOS | 5,187 | 5,672 | 6,231 |
| H3979 Blue Cross and Blue Shield of Oklahoma | HMO/HMOPOS | 2,181 | 3,906 | 3,166 |
| H8133 Blue Cross and Blue Shield of Texas | HMO/HMOPOS | 4,054 | 3,554 | 2,522 |
| H8547 Blue Cross and Blue Shield of Illinois | HMO/HMOPOS | 1,233 | 1,763 | 1,524 |
| H9460 HealthSpring | HMO/HMOPOS | 840 | 1,318 | 1,344 |
| H8554 Blue Cross and Blue Shield of OK, TX | HMO/HMOPOS | 876 | 909 | 777 |
| H2752 HealthSpring | HMO/HMOPOS | 164 | 469 | 338 |
| H0927 Blue Cross Community MMAI | Medicare-Medicaid Plan HMO/HMOPOS | 20,379 | 17,847 | n/a |
Star ratings for these contracts are in the MA Quality Dashboard.