- Missouri Department of Health and Senior Services
- Missouri Slope
- Missouri Slope Lutheran Care Center
- Missouri University
- MIT Center for Real Estate
- MIT School of Management
- Mitchell Family Office
- Mix Solutions
- Mizuho Securities USA
- MJHS Health System
- ML Healthcare
- MLive
- MNS
- Mobility Management
- Modern Healthcare
- Moderna
- Mohawk Medical Properties
- Momentum Skilled Services
- Monarch Healthcare Management
- Monida Healthcare Staffing Solutions