| Cleaning Northwest Limited | Administrative & support | 2019 |
| Cleannex Ltd | Administrative & support | 2026 |
| Cleanup Pro Ltd | Administrative & support | 2021 |
| Clear Brew Preston & Blackpool Ltd | Administrative & support | 2024 |
| Clear Flow Maintenance (NW) Limited | Administrative & support | 2026 |
| Clear Glass Holding Ltd | Financial services | 2026 |
| Clear Perspectives Limited | Administrative & support | 2004 |
| Clear Sight Cleaning Limited | Administrative & support | 2025 |
| Clear Vision Mastics Ltd | Construction | 2023 |
| Clear Vision Projects Ltd | Construction | 2022 |
| Clear Vista Limited | Real estate | 2020 |
| Clearbore Solutions Ltd | Construction | 2022 |
| Clearbus Communications Limited | Information & communication | 2006 |
| Clearcut Media Limited | Information & communication | 2006 |
| Cleardata Systems Limited | Real estate | 2009 |
| CLEARFACE49 (Holdings) Limited | Financial services | 2015 |
| CLEARFACE49 Limited | Other services | 2015 |
| Clearpath Benefit Support Ltd | Professional & scientific | 2026 |
| Clearpath Leads Limited | Other services | 2026 |
| Clearsky ADR Limited | Professional & scientific | 2017 |
| Clearview Windscreens North West Limited | Professional & scientific | 2022 |
| Clearwater Land Ltd | Real estate | 2022 |
| Clearwater Music Limited | Education | 2010 |
| Cleena Solutions Ltd | Administrative & support | 2021 |
| Clegg & Harris Ltd | Real estate | 2025 |
| Clegg's Food Service Limited | Financial services | 2024 |
| Cleggs Chesters Ltd | Hospitality | 2026 |
| Clement Commodities UK Ltd | Extraterritorial | 2022 |
| Cleminson Enterprises Limited | Wholesale & retail | 2025 |
| Clenergy (Project 4) Ltd | Energy | 2015 |
| Cleovoro Cleaning Services Limited | Administrative & support | 2026 |
| Clever Nests Limited | Information & communication | 2015 |
| Cliant Group Ltd | Professional & scientific | 2021 |
| Click Bond Limited | Manufacturing | 2013 |
| Click Corner Trading Ltd | Wholesale & retail | 2026 |
| CLICK4EXPERTS Ltd | Information & communication | 2009 |
| Client Tax Services Ltd | Professional & scientific | 2024 |
| Clif Tech Electrical Ltd | Construction | 2026 |
| Cliff House Nursery Limited | Education | 2010 |
| Cliff Howell Estates & Facilities Management Consultancy Limited | Professional & scientific | 2018 |
| Cliffcrest Limited | Households | 1975 |
| Clifford Ward Funeral Directors Limited | Other services | 2005 |
| Clifford, Poole & Co Limited | Extraterritorial | 2003 |
| Clifton Amenity Management Company Limited | Households | 1996 |
| Clifton Cottage Ltd | Hospitality | 2022 |
| Clifton Dairies Limited | Agriculture & fishing | 2005 |
| Clifton House (6 Westbeach) Ltd | Real estate | 2015 |
| Clifton House Investments Limited | Real estate | 2007 |
| Clifton Square (Burnley) Management Company Limited | Households | 2008 |
| Clifton Street Lytham SC Ltd | Households | 2025 |
| Clifton Wemmick Limited | Professional & scientific | 2015 |
| Climate and Health Awareness Ireland Ltd | Public administration | 2024 |
| Climate Revolution Acts CIC | Professional & scientific | 2026 |
| Climate Revolution Ltd | Professional & scientific | 2025 |
| Climatized Heating and Plumbing Ltd | Construction | 2026 |
| Climber Ltd | Construction | 2011 |
| Climbing Wall Training Limited | Education | 2023 |
| Clinchplain Foam and Fibre Limited | Financial services | 2025 |
| Clinizig UK Ltd | Information & communication | 2023 |
| Clip N Climb Preston Limited | Arts & recreation | 2016 |
| Clive Ashcroft Car Sales Limited | Wholesale & retail | 2011 |
| CLL (Barton 1) Limited | Construction | 2021 |
| CLM Aesthetics Limited | Other services | 2017 |
| CLM Capital Partners Limited | Professional & scientific | 2025 |
| Clock Garage (Preston) Limited | Wholesale & retail | 1999 |
| Clock Tower Media Limited | Professional & scientific | 2015 |
| Clockwork Co. Ltd | Hospitality | 2020 |
| Close Enterprises Ltd | Administrative & support | 2025 |
| Close J S Ltd | Wholesale & retail | 2023 |
| Close Protection 1 Limited | Administrative & support | 2023 |
| Close Safety Systems Ltd | Manufacturing | 2025 |
| Closetags Ltd | Information & communication | 2025 |
| Cloth Hall Properties Limited | Real estate | 2019 |
| Cloud 9 Travel & Tours Limited | Administrative & support | 2010 |
| Cloud Commerce Solutions Ltd | Information & communication | 2018 |
| Cloud Journey Solutions Ltd | Information & communication | 2020 |
| Cloud Key Networks Ltd | Wholesale & retail | 2025 |
| Cloud Solutions Holdings Limited | Financial services | 2017 |
| Cloud-Id Ltd | Information & communication | 2020 |
| CLOUD9 Promotions Ltd | Other services | 2025 |
| Cloudtal Ltd | Information & communication | 2017 |
| Clover Architectural Design Limited | Professional & scientific | 2015 |
| Clover Solar Ltd | Energy | 2025 |
| Clover Specialist Contractors Ltd | Construction | 2016 |
| CLS Financial Solutions Ltd | Professional & scientific | 2012 |
| Club 06 Limited | Wholesale & retail | 2025 |
| Club Madeira Ltd | Information & communication | 2025 |
| Clue Solutions Ltd | Administrative & support | 2018 |
| Clunans Limited | Wholesale & retail | 2002 |
| Clutch Building Ltd | Construction | 2021 |
| Clutch-Tech Ltd | Wholesale & retail | 2019 |
| CM Carpets Limited | Construction | 2010 |
| CM Contracts Ltd | Construction | 2016 |
| CM Entertainments Limited | Arts & recreation | 2016 |
| CM Home Decoration Ltd | Construction | 2024 |
| CM Integrated Solutions Ltd | Administrative & support | 2021 |
| CM IQA Ltd | Education | 2019 |
| CM Lawncare Limited | Administrative & support | 2025 |
| CMC (BP) Ltd | Hospitality | 2016 |
| CMC (Commercial) Ltd | Real estate | 2019 |