- City of Sandusky
- City of Sandy
- City of Santa Fe
- City of Santaquin
- City of Scottsdale
- City of Seven Hills
- City of Shaker Heights
- City of Sidney
- City of Solon
- City of South Euclid
- City of South Weber
- City of Spanish Fork
- City of Springville
- City of St. Anthony
- City of Sunset
- City of Syracuse
- City of Toledo
- City of Topeka
- City of Tuscon and Prima County
- City of University Heights
- City of Versailles
- City of Vineyard
- City of Vintah
- City of Warren
- City of Warrensville Heights
- City of Washington Terrace
- City of West Bountiful
- City of West Haven
- City of West Point
- City of Westlake
- City Of Wilson
- City of Winter Garden
- City of Winter Park
- City of Woodruff
- City of Youngstown
- Civil and Environmental Consultants, Inc.
- CJS Industries, Inc.
- Claiborne County
- Claiborne Memorial Medical Center
- Clairmont Oaks
- Clancy and Theys Construction Company
- Clara Maass Medical Center
- Clarence Central School District
- Clarinda Co-Op
- Clarinda Regional Health Center
- Clarion Executives Center Hotel, Omaha NE
- Clarion Hospital
- Clarion Hotel and Conference Center
- Clarion Psychiatric Center
- Clarion State Capitol - Downtown, Raleigh, NC