Ranked by total Mass. members (HMO and PPO combined) as of Dec. 31, 2014.
| Blue Cross and Blue Shield of Massachusetts Inc. | 620,705 |
| Neighborhood Health Plan Inc. | 340,264* |
| Tufts Associated HMO Inc. | 307,633 |
| Boston Medical Center Health Plans Inc. | 256,604* |
| Tufts Health Public Plans Inc. | 243,522* |
*HMO membership only; insurer does not provide a PPO plan in Mass.
Source: Health Policy Commission
