| Cleaning Angels Ltd. | Administrative & support | 2012 |
| Clear Lemon Food Ltd | Wholesale & retail | 2024 |
| Clearbase Solutions Limited | Information & communication | 2002 |
| Clearview Facilities Management Limited | Administrative & support | 2018 |
| Clearview Group Limited | Professional & scientific | 2009 |
| Clearview Magazine Ltd | Information & communication | 2009 |
| Clearway Water Solutions Ltd | Construction | 2024 |
| Clgb Ltd | Transport & logistics | 2025 |
| Clickco Limited | Wholesale & retail | 2015 |
| Cliffe Grange at Gomersall Management Limited | Real estate | 2005 |
| Cliffe Kennels Ltd | Agriculture & fishing | 2013 |
| Cliffhill Properties Limited | Construction | 1978 |
| Cliffmeur Properties Limited | Construction | 2008 |
| Cliford Ltd | Health & social care | 2016 |
| Clifteq Services Ltd | Professional & scientific | 2025 |
| Climax Screen Hire Limited | Manufacturing | 1997 |
| Clinical IT Consulting Limited | Information & communication | 2022 |
| Cliniva Cosmetic Training Ltd | Education | 2015 |
| Close Protection (London) Limited | Administrative & support | 2023 |
| Cloud 9 Support Services Limited | Administrative & support | 2012 |
| Cloud Cover 365 Limited | Information & communication | 2025 |
| Cloud Focus Ltd | Information & communication | 2012 |
| Cloud Global Consulting Ltd | Professional & scientific | 2016 |
| Cloud-Conversion Ltd | Professional & scientific | 2012 |
| CLOUD9 Childcare Ltd | Education | 2023 |
| Cloudminder Limited | Information & communication | 2022 |
| Cloudops Solutions Ltd | Administrative & support | 2022 |
| Clough (Croydon) Limited | Manufacturing | 1936 |
| Cloughfields Convenience Ltd | Wholesale & retail | 2026 |
| Clover Inc (Durham) Limited | Real estate | 2022 |
| Clowery Homes Ltd | Construction | 2021 |
| Clowery Limited | Construction | 2003 |
| CLP Asset Holding Limited | Real estate | 2025 |
| Clplw Holdings Ltd | Financial services | 2023 |
| Club Active CIC | Education | 2023 |
| Club Connect GG Limited | Other services | 2025 |
| Clubcaddy Golf Ltd | Manufacturing | 2025 |
| Cluntergate Management Company Limited | Households | 2016 |
| CLW Plant & Commercial Ltd | Manufacturing | 2026 |
| CM Auto Repair Centre Ltd | Wholesale & retail | 2022 |
| Cmade Outdoors Ltd | Education | 2022 |
| Cmak Films Ltd | Information & communication | 2021 |
| Cmbr Transport Limited | Transport & logistics | 2020 |
| Cmcgee Ltd | Professional & scientific | 2007 |
| CMD Wire Products Ltd | Manufacturing | 2015 |
| Cmere Pulluck Ltd | Administrative & support | 2018 |
| CMH Wealth Management Ltd. | Financial services | 2015 |
| CMJ Window and Door Services Ltd | Construction | 2026 |
| Cmkinfluence Ltd | Professional & scientific | 2024 |
| Cmol Limited | Information & communication | 2026 |
| CMS Express Ltd | Transport & logistics | 2025 |
| CMS Wardrobes Ltd | Wholesale & retail | 2016 |
| CMW Estates Ltd | Real estate | 2024 |
| CNC Universe Ltd | Wholesale & retail | 2020 |
| Cncenery Limited | Manufacturing | 2024 |
| Coachinginschools.Com Ltd | Education | 2011 |
| Coalesce Recruitment Limited | Administrative & support | 2020 |
| Cobalto Ltd | Construction | 2019 |
| Cobcar Limited | Wholesale & retail | 2026 |
| Cockerels Woods at Leeds New Forest Village Management Company Limited | Real estate | 2006 |
| Coco LC Ltd | Wholesale & retail | 2024 |
| Coco Mocha Films Ltd | Information & communication | 2020 |
| Cocoandrian Ltd | Health & social care | 2021 |
| Coconut Creatives Ltd | Professional & scientific | 2011 |
| Code Crafters Software Limited | Information & communication | 2008 |
| Codeverse Limited | Administrative & support | 2017 |
| Coding With Coffee Ltd | Information & communication | 2024 |
| Coffee Wizard Limited | Other services | 2020 |
| Cogly Limited | Information & communication | 2025 |
| Colin Chadburn Financial Planning Ltd | Financial services | 2019 |
| Colin Vaines Transport Limited | Transport & logistics | 2012 |
| College House Barnsley Management Company Limited | Professional & scientific | 2005 |
| Colley Croft Cafe Limited | Hospitality | 2011 |
| Collie Flowers Ltd | Agriculture & fishing | 2022 |
| Collinwood Enterprise Ltd | Hospitality | 2024 |
| Colonia Investments Limited | Financial services | 2024 |
| Colonia Properties Limited | Other services | 2021 |
| Colophon Trade Limited | Wholesale & retail | 2026 |
| Colorwise Painting Limited | Construction | 2025 |
| Colour@ Ltd | Arts & recreation | 2019 |
| Colt Line Express Ltd | Transport & logistics | 2025 |
| Coltech Global Limited | Financial services | 2019 |
| Coltech Recruitment Ltd | Information & communication | 2018 |
| Colton Estate Ltd | Real estate | 2022 |
| Columbia Windows Limited | Construction | 2016 |
| Colverson Consultancy Ltd | Professional & scientific | 2026 |
| Combat Events & Apparel Ltd | Arts & recreation | 2019 |
| Combineunit Limited | Real estate | 1989 |
| Comfort Zone Plumbing & Heating Solutions Limited | Construction | 2015 |
| Command Utilities Ltd | Construction | 2026 |
| Commercial Glass Specialists Limited | Manufacturing | 2026 |
| Commercial Properties (Wakefield) Ltd | Real estate | 2018 |
| Comms Yorkshire Limited | Professional & scientific | 2023 |
| Communicom H & H Ltd | Wholesale & retail | 2003 |
| Community Alliances Limited | Professional & scientific | 2015 |
| Community Health and Wellbeing Limited | Arts & recreation | 2020 |
| Community Shop C.I.C. | Wholesale & retail | 2013 |
| Compa Construction Ltd | Construction | 2026 |
| Company 1968 Ltd | Real estate | 2016 |
| Company Shop Limited | Wholesale & retail | 1985 |