| BYD Service Centre Milton Keynes | Oil change service | Northfield Dr | Mon–Fri 08:30–18:00 |
| CadRalph Design II | Design engineer | 7 Langton Dr | Sat 11:00–18:00 |
| Can-Do Services | Agricultural service | The Old Dairy Farm, Mill Ln | Fri 08:00–17:00 |
| Captain Ridley's Shooting Party | Pub | 183-185 Queensway | Mon–Thu 08:00–00:00 |
| Caralevel Fully Automatic Caravan Levelling System | Caravan supply shop | Springhill Farm, Little Horwood Rd | Mon–Sat 09:30–18:00 |
| Career Clinic Net | Career guidance service | 7 Ultra Ave | Mon–Fri 09:00–17:00 |
| Carpetwise | Carpet retail shop | 2a High St | Wed–Sat 10:00–16:00 |
| Carters | Estate agent | 194 Queensway | Daily 09:00–18:00 |
| Carters Ear Clear Clinic | Audiologist | 12a Benbow Ct | Mon 15:00–17:15 |
| Carters mk ltd | Vehicle repair shop | 1 The Oval | Mon–Fri 08:00–18:00 |
| Carters Rentals | Property rental agency | Buckinghamshire County, 59 High St | Mon–Tue 09:00–17:30 |
| Celestra | IT support and services | 1-5 James Way | Mon–Fri 08:30–17:30 |
| Central Moves Milton Keynes | Removals service | ISU 3, 11 Bilton Rd | Mon 08:30–17:30 |
| Chadwick Drive - Anchor | Housing association | Milton Keynes MK6 5LS | Daily Open 24 hours |
| Chaineys Cycles | Bicycle shop | 15 Benbow Ct | Mon–Fri 09:30–18:00 |
| Charles Tyrwhitt Milton Keynes | Fashion accessories shop | Unit 27 Silbury Boulevard Centre | Mon–Fri 10:00–19:00 |
| Chiltern ADHD Clinic | Mental health clinic | The Hollows Business Park, Unit 3 D&E Winslow Rd | Mon–Fri 09:00–17:00 |
| Church of Christ the Cornerstone | Church | 300 Saxon Gate | Mon–Sat 09:00–18:00 |
| Citroën Perrys Milton Keynes | Citroen dealer | Bilton Rd | Mon 08:30–18:00 |
| Clarke Rendall | Office furniture shop | 12, Denbigh hall industrial estate, Denbigh Hall Dr | Mon–Thu 07:00–17:00 |
| CleanTech MK | Cleaners | Scorpio House, Rockingham Dr | Daily Open 24 hours |
| Clock Property Milton Keynes: Commercial Property Estate Agents | Commercial property estate agent | Milton Keynes Business, Business Centre, Foxhunter Dr | Mon–Fri 09:00–17:30 |
| CloudNine Creative Interiors | Furniture manufacturer | Unit 1, The Barn, Shucklow Hill | Mon–Fri 08:00–17:00 |
| Collaborate MK Business Networking Milton Keynes | Business networking company | 17 Rolvenden Grove | Mon–Fri 07:30–20:00 |
| Complete Electronics | Electronics manufacturer | Unit 32, Business Centre, 36 Lodge Farm Ln | Mon–Thu 08:00–16:00 |
| Complete Water Care | Water testing service | Birchen Lee | Daily Open 24 hours |
| Computamedic | Computer service | 17 The Oval | Thu 08:00–20:00 |
| Computer Discounts | Computer shop | 2 Maryland Rd | Thu 09:00–17:30 |
| Confidence IT Ltd | Computer service | Unit 2, Brookland Farm, The Courtyard | Mon–Fri 08:00–17:30 |
| Connolly Accountants & Business Advisors Ltd | Accountant | The Stable Yard, Vicarage Rd | Mon–Fri 09:00–17:00 |