| Cloud Coach UK Limited | Information & communication | 2023 |
| CLOUD9 Power Limited | Energy | 2026 |
| Cloudvplus Holdings Ltd | Administrative & support | 2023 |
| Clovelly Property Holdings UK Limited | Construction | 2025 |
| Cloxart Ltd | Professional & scientific | 2025 |
| Club Commerce Architecture Ltd | Construction | 2020 |
| Cluck & Crisp Limited | Hospitality | 2025 |
| Cluster Estates Limited | Administrative & support | 1981 |
| Clusura Limited | Financial services | 2020 |
| Clyse Limited | Wholesale & retail | 2025 |
| CMB Accountancy Services Southern Ltd | Professional & scientific | 2017 |
| CMD Properties Limited | Real estate | 2006 |
| CMI (SW) Limited | Professional & scientific | 2015 |
| Cmsb Management Limited | Real estate | 2024 |
| Cmsb Property Investments Limited | Real estate | 2017 |
| CNB Plastering Services Limited | Construction | 2012 |
| CNC Consultants Ltd | Professional & scientific | 2023 |
| CNJ Valeting Ltd | Administrative & support | 2024 |
| CNP Car Sales Ltd | Wholesale & retail | 2024 |
| CNP Training and Consultancy Ltd | Information & communication | 2016 |
| Co-Living (Monks) Limited | Real estate | 2025 |
| Co-Living South 2 Ltd | Real estate | 2025 |
| Co-Living South Holdings Ltd | Financial services | 2024 |
| Co-Living South Ltd | Real estate | 2021 |
| Co-Living South Trading Ltd | Real estate | 2024 |
| Co-Operative Franchising Limited | Wholesale & retail | 2008 |
| Co-Operative Independent Living Limited | Wholesale & retail | 2008 |
| Coast Dental Health & Beauty Ltd | Health & social care | 2011 |
| Coast Practice Assets Limited | Health & social care | 2014 |
| Coast Practice Property Ltd | Real estate | 2021 |
| Coastal Building Solutions Ltd | Construction | 2025 |
| Coastal Electrical Installations Ltd | Construction | 2020 |
| Coastguard Cafe Limited | Hospitality | 2014 |
| Coastlister Limited | Hospitality | 1979 |
| Coastmade Ltd | Information & communication | 2026 |
| Cobalt Homes Limited | Real estate | 2018 |
| Cobb Financial IOW Limited | Professional & scientific | 2021 |
| Cobra Coffee Limited | Hospitality | 2013 |
| Cobra Coffee South West Limited | Hospitality | 2013 |
| Cobra Energy Ltd | Energy | 2018 |
| Cobra Tool & DIE Limited | Manufacturing | 2009 |
| Cocktail 25 Ltd | Hospitality | 2024 |
| Coco the Bossman Ltd | Hospitality | 2022 |
| Coconnect Limited | Information & communication | 2008 |
| Cocotte Limited | Hospitality | 2017 |
| Code Red Productions Ltd | Professional & scientific | 2014 |
| Codeport.Pro Ltd | Information & communication | 2025 |
| Codeveloped Limited | Information & communication | 2016 |
| Coensan Limited | Financial services | 2023 |
| Coeus Technical Ltd | Professional & scientific | 2021 |
| Coffee House Express Limited | Hospitality | 2018 |
| Coffee Karma Limited | Hospitality | 2019 |
| Coffee Moustache Ltd | Wholesale & retail | 2021 |
| Coffeeland Limited | Extraterritorial | 2001 |
| Cognatio Property Investments Limited | Real estate | 2020 |
| Cognatio Residential Property Investments Limited | Real estate | 2025 |
| Cogniva Limited | Administrative & support | 2014 |
| Cohabit Homes Ltd | Real estate | 2025 |
| Coin Collectors Club Ltd | Wholesale & retail | 2023 |
| Coity Estates Limited | Construction | 2024 |
| COL Limited | Financial services | 2026 |
| Colchester Road 1958 Limited | Extraterritorial | 2014 |
| Colchester Road 1960 Limited | Extraterritorial | 2014 |
| Colebrook Avenue Limited | Health & social care | 2023 |
| Coles Construction Ltd | Construction | 2026 |
| Colgate Rental Ltd | Real estate | 2026 |
| Colia Chekaoui Coaching Ltd | Wholesale & retail | 2021 |
| Colin S. Good Property Limited | Real estate | 2004 |
| Colin Walker Composites Ltd | Manufacturing | 2017 |
| Colin Williams Plastering Ltd | Construction | 2025 |
| College Farm Barn Developments Ltd | Construction | 2024 |
| Collier & Jeremy Properties Ltd | Real estate | 2018 |
| Collier Group Holdings Limited | Financial services | 2026 |
| Collier Jeremy Ltd | Real estate | 2012 |
| Colligan Builders Limited | Construction | 2019 |
| Collingwood Residential Garaging Ltd | Real estate | 2019 |
| Collins Financial Enterprises Ltd | Financial services | 2024 |
| Collins Pipe Construction Ltd | Construction | 2018 |
| Collins Quality Services Ltd | Professional & scientific | 2024 |
| Collins Ward Capital Management Limited | Administrative & support | 2006 |
| Colour Balance Images Ltd | Wholesale & retail | 2017 |
| Colourtech Limited | Wholesale & retail | 2000 |
| Colt and Cross Limited | Wholesale & retail | 2021 |
| Coltart Medical Services Ltd | Health & social care | 2022 |
| Combat Games Distribution Limited | Wholesale & retail | 2021 |
| Combat South Limited | Arts & recreation | 2002 |
| Combo Clean Ltd | Administrative & support | 2026 |
| Come GET Some Limited | Hospitality | 2025 |
| Comfort Real Estates Ltd | Real estate | 2022 |
| Comforting Hearts Homecare Limited | Health & social care | 2026 |
| Commercial Building Solutions Limited | Construction | 2013 |
| Commercial Energy Claims Limited | Other services | 2023 |
| Commercial Litigation Group Limited | Financial services | 2017 |
| Commercial Success Ltd | Professional & scientific | 2025 |
| Common Ground Education Limited | Education | 2026 |
| Communications South Limited | Information & communication | 1989 |
| Community Response SAR Team Portsmouth Ltd | Administrative & support | 2025 |
| Community Spotlight CIC | Other services | 2022 |
| Company 13212477 Limited | Administrative & support | 2021 |
| Compare Sky FLY Parking Deals Ltd | Administrative & support | 2019 |