| Maple Heights Behavioral Health | Fort Wayne, IN | Psychiatric | Not rated |
| Maria Parham Medical Center | Henderson, NC | Acute Care Hospitals | 2 stars |
| Marian Center | Salt Lake City, UT | Psychiatric | Not rated |
| Marion Communtiy Hospital | Ocala, FL | Acute Care Hospitals | 1 star |
| Mayaguez Medical Center Dr Ramon Emeterio Betances | Mayaguez, PR | Acute Care Hospitals | 1 star |
| Mayhill Hospital | Denton, TX | Acute Care Hospitals | Not rated |
| Meadows Psychiatric Center | Centre Hall, PA | Psychiatric | Not rated |
| Meadowview Regional Medical Center | Maysville, KY | Acute Care Hospitals | 4 stars |
| Meadowwood Behavioral Health System | New Castle, DE | Psychiatric | Not rated |
| Medical Behavioral Hospital - Mishawaka | Mishawaka, IN | Psychiatric | Not rated |
| Medical Behavioral Hospital of Clear Lake, LLC | Clear Lake City, TX | Psychiatric | Not rated |
| Medical Behavioral Hospital of Indianapolis | Greenwood, IN | Psychiatric | Not rated |
| Medical Center Enterprise | Enterprise, AL | Acute Care Hospitals | 4 stars |
| Medical Center of McKinney | McKinney, TX | Acute Care Hospitals | 3 stars |
| Medical City Arlington | Arlington, TX | Acute Care Hospitals | 2 stars |
| Medical City Dallas Hospital | Dallas, TX | Acute Care Hospitals | 3 stars |
| Medical City Denton | Denton, TX | Acute Care Hospitals | 4 stars |
| Medical City Fort Worth | Fort Worth, TX | Acute Care Hospitals | 2 stars |
| Medical City las Colinas | Irving, TX | Acute Care Hospitals | 4 stars |
| Medical City Mental Health and Wellness Center | Fort Worth, TX | Psychiatric | Not rated |
| Medical City Mental Health and Wellness Center | Frisco, TX | Psychiatric | Not rated |
| Medical City North Hills | North Richland Hills, TX | Acute Care Hospitals | 2 stars |
| Medical City Plano | Plano, TX | Acute Care Hospitals | 3 stars |
| Medical City Weatherford | Weatherford, TX | Acute Care Hospitals | 2 stars |
| Medstar Georgetown University Hospital | Washington, DC | Acute Care Hospitals | 3 stars |
| Memorial Health Meadows Hospital | Vidalia, GA | Acute Care Hospitals | 5 stars |
| Memorial Hermann Surgical Hospital Kingwood | Kingwood, TX | Acute Care Hospitals | Not rated |
| Memorial Hospital Biloxi | Biloxi, MS | Acute Care Hospitals | 1 star |
| Memorial Hospital of Gardena | Gardena, CA | Acute Care Hospitals | 1 star |
| Memorial Medical Center | Las Cruces, NM | Acute Care Hospitals | 2 stars |
| Memorialcare Orange Coast Medical Center | Fountain Valley, CA | Acute Care Hospitals | 4 stars |
| Menifee Global Medical Center | Sun City, CA | Acute Care Hospitals | Not rated |
| Menorah Medical Center | Overland Park, KS | Acute Care Hospitals | 3 stars |
| Mental Health Services for Clark and Madison Cos | Springfield, OH | Psychiatric | Not rated |
| Mercy Behavioral Hospital | Lecompte, LA | Psychiatric | Not rated |
| Mercy Health - Defiance Hospital | Defiance, OH | Acute Care Hospitals | 4 stars |
| Mercy Hospital Watonga, Inc | Watonga, OK | Critical Access Hospitals | Not rated |
| Mercy Regional Medical Center | Ville Platte, LA | Acute Care Hospitals | 3 stars |
| Merit Health Central | Jackson, MS | Acute Care Hospitals | 3 stars |
| Merit Health Madison | Canton, MS | Acute Care Hospitals | 3 stars |
| Merit Health Natchez | Natchez, MS | Acute Care Hospitals | 2 stars |
| Merit Health River Oaks | Flowood, MS | Acute Care Hospitals | 1 star |
| Merit Health River Region | Vicksburg, MS | Acute Care Hospitals | 2 stars |
| Merit Health Women's Hospital | Flowood, MS | Acute Care Hospitals | Not rated |
| Mesa Springs | Fort Worth, TX | Psychiatric | Not rated |
| Mesa View Regional Hospital | Mesquite, NV | Critical Access Hospitals | 2 stars |
| Methodist Hospital | San Antonio, TX | Acute Care Hospitals | 4 stars |
| Methodist Hospital Stone Oak | San Antonio, TX | Acute Care Hospitals | 4 stars |
| Methodist Hospital Atascosa | Jourdanton, TX | Acute Care Hospitals | 3 stars |
| Methodist Hospital for Surgery | Addison, TX | Acute Care Hospitals | 4 stars |