| Circulate Digital Sheffield | Internet marketing service | Fl 3, Castle St | Mon 09:00–18:00 |
| City Centre Tai Chi, Qigong, Taoist Yoga, Meditation, Self-Defence | Tai chi school | St Tim's Community Hall, 136 Slinn St | Mon 19:15–20:45 |
| City Limits Dance Centre | Dance school | 607-613 Penistone Rd | Mon–Thu 09:00–21:00 |
| City Limits Venue | Function room facility | 607-613 Penistone Rd | Daily Open 24 hours |
| City of Refuge Foursquare Church | Foursquare church | 217 Handsworth Rd | Sun 10:00–13:00 |
| City Seals & Bearings Ltd | Bearing supplier | City Seals and Bearings Ltd, Stevenson Rd | Mon–Fri 07:45–17:30 |
| Cleaning Angels Yorkshire Ltd | House cleaning service | suite 3, Crown House, Market St | Mon–Fri 09:00–17:00 |
| Clear Links Support | Disability services and support organization | The Portergate, 257 Ecclesall Rd | Mon–Fri 09:00–17:00 |
| ClearStep Podiatry & Chiropody Ltd | Chiropodist | 56 Holme Ln | Mon–Sat 09:00–19:00 |
| ClubRackets.com | Tennis shop | 5 Dyson Pl | Thu 11:00–18:30 |
| Co-op Legal Services | Divorce lawyer | John Banner Building, 620 Attercliffe Rd | Mon 09:00–17:30 |
| Cocoa Wonderland | Chocolate shop | 462 Ecclesall Rd | Tue–Sat 10:00–17:00 |
| Coldco Group | Commercial refrigerator supplier | Unit 9, Industrial Estate, Retford Rd | Mon–Fri 09:00–17:30 |
| Collette State Therapies | Reflexologist | 65 Springwell Grove | Mon 14:30–18:00 |
| Collins water products Ltd | Water filter supplier | 15 Storth Ln | Mon–Fri 09:00–17:00 |
| Colour Guru Jen - Seasonal Colour Analysis | Image consultant | 33 Vainor Rd | Mon 09:00–15:00 |
| Colour Kote Ltd | Painting | Unit 14, Evans Business Centre, Nobel Way | Mon–Fri 09:00–17:30 |
| Complete Stair Creations | Stair contractor | 870 Penistone Rd | Mon–Fri 09:00–17:00 |
| Concept Systems Ltd | Printer repair service | 289 Chesterfield Rd | Mon–Fri 09:30–17:00 |
| Cooper's Car Spares | Car breaker | Livesey St | Mon–Fri 08:30–16:00 |
| Cooplands | Bakery | Unit 2, 146 Langsett Rd S | Mon–Sat 07:30–16:00 |
| COOPS Switchgear Limited | Electrical equipment supplier | 68, 70 Catley Rd | Mon–Thu 07:00–17:30 |
| Correct Choice Windows & Doors Ltd | Window installation service | 32 Eyre St | Mon–Fri 08:00–17:30 |
| Counter Grappling | Jiu jitsu school | 479-481 Manchester Rd | Mon 06:15–07:45 |
| Cowboy Boot Store | Tienda de botas | 97 Division St | Mon–Fri 11:00–18:00 |
| Craft & Berry | Off licence | 369 Ecclesall Rd | Thu 11:00–19:00 |
| Cranial Health | Craniosacral therapy | 8a, Outgang Lane BizSpace | Mon–Fri 10:00–18:00 |
| CrossFit Sheffield | Physical fitness programme | H19 Prospect rd | Mon–Fri 06:30–20:30 |
| CRS Accident Repair Centre - Dinnington | Car body shop | Unit 28, 29 Kingfisher Wy | Mon–Fri 08:00–17:00 |
| Crystal Conservatories Ltd | Conservatory contractor | 2a Orgreave Dr | Fri 08:00–16:30 |