MA Enrollment Explorer / Parent organizations / CareSource
CareSource: Medicare Advantage enrollment and market share
CareSource had 86,593 Medicare Advantage members in October 2026, #36 nationally with 0.24% of all MA enrollment. It gained 18,045 members (+26.3%) since October 2025, and has enrollment in 8 states and 134 counties with 11 or more members, leading the market in 1 of them. In the 2026 Annual Election Period (December to February) it gained 7,558 members (+11.0%). For 2027, 662 of its members are in plans that terminate and 86 in plans leaving their county, and it leaves 20 counties entirely.
87KMA members, October 2026
+26.3%change since October 2025 (+18,045)
0.24%national MA share, rank 36
7contracts with enrollment
Largest states
| State | Members | Share of state MA |
|---|---|---|
| Massachusetts | 44,731 | 8.3% |
| Ohio | 38,483 | 2.6% |
| New York | 894 | 0.0% |
| Wisconsin | 743 | 0.1% |
| Georgia | 724 | 0.1% |
| New Hampshire | 42 | 0.0% |
| Rhode Island | 18 | 0.0% |
| Connecticut | 15 | 0.0% |
Largest counties
| County | Members | Change since October 2025 | Share of county MA |
|---|---|---|---|
| Hampden County, MA | 13,479 | −80 | 27.0% |
| Cuyahoga County, OH | 10,571 | +3,791 | 6.5% |
| Suffolk County, MA | 5,884 | +79 | 12.1% |
| Middlesex County, MA | 5,309 | −10 | 5.0% |
| Essex County, MA | 5,259 | −163 | 8.1% |
| Worcester County, MA | 3,777 | −65 | 4.7% |
| Summit County, OH | 3,677 | +1,613 | 4.5% |
| Bristol County, MA | 2,899 | +63 | 5.5% |
| Plymouth County, MA | 2,692 | +84 | 6.4% |
| Norfolk County, MA | 2,512 | +143 | 5.1% |
| Stark County, OH | 2,510 | +791 | 3.9% |
| Mahoning County, OH | 2,441 | +807 | 6.2% |
| Lorain County, OH | 2,024 | +605 | 4.4% |
| Franklin County, OH | 1,890 | +1,006 | 1.6% |
| Trumbull County, OH | 1,729 | +571 | 5.1% |
Contracts
| Contract | Plan type | Oct 2024 | Oct 2025 | Oct 2026 |
|---|---|---|---|---|
| H6396 CareSource MyCare Ohio (HMO D-SNP) | HMO/HMOPOS | 4,251 | 8,394 | 38,781 |
| H1486 Commonwealth Care Alliance, Inc. | HMO/HMOPOS | n/a | n/a | 25,867 |
| H2225 Commonwealth Care Alliance Massachusetts | HMO/HMOPOS | 16,612 | 16,974 | 19,259 |
| H8390 CareSource | HMO/HMOPOS | 0 | 105 | 962 |
| H6776 ElderServe Health | HMO/HMOPOS | 476 | 853 | 908 |
| H5212 Community Care | National PACE | 481 | 489 | 511 |
| H2034 Community Care | HMO/HMOPOS | 483 | 479 | 305 |
| H0137 Commonwealth Care Alliance | Medicare-Medicaid Plan HMO/HMOPOS | 29,954 | 28,025 | n/a |
| H8452 CareSource MyCare Ohio | Medicare-Medicaid Plan HMO/HMOPOS | 14,957 | 13,229 | n/a |
Star ratings for these contracts are in the MA Quality Dashboard.