| C Mayer Properties Limited | Real estate | 2011 |
| C Mcbride Property Management and Services Ltd | Households | 2023 |
| C Millar & SON Fabrications Limited | Manufacturing | 2010 |
| C P Naval Ltd | Construction | 2026 |
| C Pearce Property Ltd | Households | 2024 |
| C R Stanley Carpets (Plymouth) Limited | Manufacturing | 2014 |
| C S Ryder Holdings Limited | Financial services | 2021 |
| C Smallwood Fencing Limited | Construction | 2024 |
| C T B Book Keeping Limited | Professional & scientific | 2013 |
| C T Consultancy & Training Ltd | Education | 2016 |
| C Wright Electrical Limited | Construction | 2017 |
| C&A Dynamic Ltd | Wholesale & retail | 2019 |
| C&F Rowe Holdings Limited | Financial services | 2025 |
| C&G Tourist Attractions Limited | Arts & recreation | 2006 |
| C&H Tree Surgery Ltd | Agriculture & fishing | 2019 |
| C&J Takeaways Ltd | Hospitality | 2022 |
| C&L 23 Limited | Wholesale & retail | 2023 |
| C&R Property (SW) Limited | Hospitality | 2023 |
| C&S Taxi Rentals Limited | Transport & logistics | 2023 |
| C&V Transco Ltd | Transport & logistics | 2023 |
| C. COX Limited | Construction | 2003 |
| C.A.B. Special Batteries Ltd. | Manufacturing | 1982 |
| C.A.M Drylining Ltd | Construction | 2025 |
| C.J. Pearce & SON Limited | Professional & scientific | 2004 |
| C.S I. (SW) Ltd | Construction | 2012 |
| C.Smith Plumbing & Heating Limited | Wholesale & retail | 1990 |
| CA Energy Services Limited | Construction | 2019 |
| CA Property Holdings SW Ltd | Real estate | 2024 |
| Cabx Plymouth Limited | Transport & logistics | 2025 |
| Cacao Tree Restaurant & Bar Ltd | Hospitality | 2022 |
| Cactus 020 Limited | Wholesale & retail | 2011 |
| Cactus Lets Ltd | Real estate | 2019 |
| CAD Hatter Limited | Professional & scientific | 2019 |
| Caddology Limited | Information & communication | 2008 |
| Cade & Co Collective Ltd | Wholesale & retail | 2025 |
| Cadmech Projects Limited | Administrative & support | 2005 |
| Caerphilly Warehouse Ltd | Real estate | 2026 |
| Cafe Momus Ltd | Hospitality | 2025 |
| Cafe Norfolk Coast Ltd | Hospitality | 2019 |
| Cafe Pier One Looe Ltd | Hospitality | 2023 |
| Cafe Plus Mutley Ltd | Hospitality | 2023 |
| Cafe Roma Limited | Hospitality | 2003 |
| Caffe SOL (Mutley Plain) Ltd | Hospitality | 2011 |
| Café Roma the HOE Limited | Hospitality | 2023 |
| Cairo Securities Limited | Real estate | 1984 |
| CAITLIN220389 Limited | Administrative & support | 2025 |
| Cakewhole Limited | Wholesale & retail | 2023 |
| Cala Court Management Limited | Households | 2018 |
| Calconord Limited | Real estate | 2025 |
| Calibre Advisors Ltd | Other services | 2017 |
| Calico Developments South West Ltd | Construction | 2018 |
| Callighan SOL Limited | Construction | 2018 |
| Callington MOT and Service Centre Limited | Wholesale & retail | 2025 |
| Callister and Winkler Limited | Administrative & support | 2017 |
| Calpri Plumbing & Heating Ltd | Construction | 2017 |
| Calum Campbell-Coles Design Ltd | Professional & scientific | 2023 |
| Calvert Healthcare Consulting Limited | Professional & scientific | 2015 |
| Camck Ltd | Professional & scientific | 2018 |
| Camden Court (Management) Plymouth Limited | Households | 1990 |
| Camellia Catering Ltd | Hospitality | 2014 |
| Camgan Ltd | Manufacturing | 2010 |
| Camogen Limited | Information & communication | 2007 |
| Camogli Holdings Ltd | Financial services | 2023 |
| Camomile Lawn Management Company Limited | Households | 2026 |
| Camp Membership CIC | Education | 2019 |
| Campbell & Hollister Group Limited | Construction | 2025 |
| Campbell Family Property Ltd | Real estate | 2024 |
| Campbell Properties Devon Limited | Construction | 2014 |
| CAMPERS4RENTAL Limited | Administrative & support | 2021 |
| Canadian Muffin Co Ltd | Hospitality | 2025 |
| Cann Down Farm | | 1999 |
| Cannixa Ltd | Agriculture & fishing | 2019 |
| Canno Construction Ltd | Construction | 2025 |
| Canwe Ltd | Construction | 2013 |
| Cape Ross Properties Ltd | Real estate | 2018 |
| Capital Agri Ltd | Other services | 2019 |
| Capital FC Limited | Hospitality | 2024 |
| Capstan Travel Limited | Extraterritorial | 1969 |
| Capsule Care Limited | Professional & scientific | 2023 |
| Captain's House Kingsbridge Limited | Households | 2004 |
| Car Master MCR Ltd | Wholesale & retail | 2019 |
| Car Medical Center Ltd | Administrative & support | 2014 |
| Car Sales Plymouth Ltd | Wholesale & retail | 2024 |
| Car Shine System Ltd | Wholesale & retail | 2019 |
| Car to Car Plymouth Ltd | Wholesale & retail | 2020 |
| Car to Coach Vehicle Refinishers Ltd | Wholesale & retail | 2014 |
| Car Wash Developments Ltd | Manufacturing | 2008 |
| Car Wash Plymouth Ltd | Other services | 2018 |
| Caradoc-Hodgkins Architects Ltd | Professional & scientific | 2011 |
| Caradog Properties Limited | Real estate | 2022 |
| Caradon Court Freehold Limited | Households | 1991 |
| Caramber Marine Limited | Professional & scientific | 2002 |
| Carbon 7 Consultancy Ltd | Professional & scientific | 2024 |
| Carbon Saving Group Holdings Limited | Financial services | 2021 |
| Carbon Saving Group Limited | Construction | 2015 |
| Carbon Saving Group Retail Ltd | Construction | 2021 |
| Carbonfourteen Ltd | Professional & scientific | 2022 |
| Carbonish Structures Ltd | Manufacturing | 2017 |
| Carclaze Limited | Households | 2001 |
| Cardiff Pizza Time Ltd | Hospitality | 2019 |