- CDC
- CDW
- Cedar Community
- Cedar County Republican
- Cedar Health Group
- Cedar Pointe Health and Wellness Center
- Cedar Ridge Health & Rehabilitation Center
- Cedar Sinai Park
- Cedar Village
- Cedarcare Holdings
- Cedarvale Terrace Long Term Care Home
- Celltrion
- Celtic Consulting
- CenCal Health
- Centene
- Centennial Adultcare Center
- Center for Aging Research and Education
- Center for Consumer Engagement in Health Innovation
- Center for Disease Control and Prevention
- Center for Economic and Policy Research