Organizers
- Cooper Tennis Complex
- Cooperative Arts and Humanities High School
- Cooper's Hawk Golf Club
- Cooperstown Backyard Baseball Classic
- Cooperstown Baseball World
- Coosaw Creek Country Club
- Cootehill Chamber of Commerce
- Copper Basin Bible Camp
- Copper Canyon Golf Club
- Copper Hill Golf Club & Academy
- Copperas Cove Parks and Rec Dept
- Cops and Kids
- Cops for Kids with Cancer
- Coquitlam Sharks Aquatic Club
- Coral Reef Swim Race
- Coral Ridge Country Club
- Coralville Community Food Pantry
- Coralville Parks & Recreation Department
- Coralville Parks and Recreation Department
- CORBIN POLICE DEPT.
- Corcoran Chamber of Commerce
- Cordele-Crisp Chamber of Commerce
- Cordova Golf Course
- Cordova Recreation and Park District
- Core Athletics LLC
- Coretiming
- Cor-Fit Gym
- Cork Association for Autism
- Corlears School
- Corner Store Country Run
- Cornerstone Charter Academy
- Cornerstone Christian Church
- Cornerstone Christian School
- Cornerstone Church
- Cornerstone Day Camp
- Cornerstone Masonic Historical Society
- Cornerstone Ranch
- Cornerstone University Sports Camps
- Corning High School Sports Association - Boosters Club
- Cornshucker Baseball
- Cornshucker Baseball Club
- Cornwall Lions Club
- Corona del Mar Chamber of Commerce
- Corona Eagles FC
- Corona Girls Softball Association
- Corona National Little League
- Coronado Islanders
- Coronado Little League
- Coronado Surf Club
- Coronado Tennis Center in Hot Springs Village