- Merck
- Mercy Health Services
- Mercy Ministries
- Meridian Capital Group
- Methodist Home for Nursing and Rehabilitation
- Methodist Homes of Alabama & Northwest Florida
- Methodist Retirement Communities
- MetroHealth
- Metron Integrated Health Services
- Metta Healthcare
- MG Medical Products
- Miami Jewish Health
- Michaud Residential Health Services
- Michigan Christian Home
- Michigan Health Endowment Fund
- Michigan Medicine
- Michigan State University
- Michigan Veterans Home
- Michigan Veterans Home at Chesterfield Township
- Mid-Atlantic Health