| BVC Investments Limited | Financial services | 2022 |
| BW Property Maintenance Limited | Administrative & support | 2022 |
| BWM (UK) Limited | Manufacturing | 2014 |
| BY Dufie Limited | Wholesale & retail | 2022 |
| BYM Electrical Ltd | Construction | 2019 |
| Bytesize Training & Consultancy Limited | Information & communication | 2008 |
| Bytn Ltd | Wholesale & retail | 2022 |
| C & F Transport Limited | Transport & logistics | 1996 |
| C & G Installations Limited | Construction | 2007 |
| C & R Property Solutions Ltd | Real estate | 2025 |
| C & S GAS Services Ltd | Construction | 2018 |
| C B P O Retail Limited | Wholesale & retail | 2016 |
| C D Ridgway Scaffolding Limited | Construction | 2021 |
| C Davies Services Ltd | Construction | 2025 |
| C G Controls Limited | Construction | 2017 |
| C H Access Solutions Ltd | Construction | 2024 |
| C H E Plumbing and Heating Ltd | Construction | 2023 |
| C J Body Services Limited | Water & waste | 2023 |
| C J Carpentry Limited | Construction | 2018 |
| C J Motor Services (Kent) Ltd | Wholesale & retail | 2020 |
| C N Hoare Ltd | Construction | 2024 |
| C P Towell Ltd | Construction | 2021 |
| C S Developers Limited | Construction | 2023 |
| C&D Event Solutions Ltd | Administrative & support | 2021 |
| C&G Building & Maintenance Ltd | Construction | 2018 |
| C&H Land and Property Investments Ltd | Real estate | 2023 |
| C&K Barbers Limited | Other services | 2026 |
| C&S Roofing Consultancy Ltd | Construction | 2018 |
| C'Sters Ltd | Health & social care | 2023 |
| C. T. a. Maintenance Limited | Other services | 1985 |
| C.E. Associates Ltd | Professional & scientific | 2011 |
| C.E.R Parker Limited | Public administration | 2021 |
| C.G. Baker Joinery Limited | Construction | 1999 |
| C.G.N Medical Ltd | Health & social care | 2021 |
| C.J Hooks Ltd | Wholesale & retail | 2026 |
| C.J. Pert Limited | Wholesale & retail | 2005 |
| C.L.I.P Surveys Ltd | Professional & scientific | 2016 |
| C.P.A. Plumbing & Heating Ltd | Construction | 2023 |
| Cabrini 3 Limited | Real estate | 2019 |
| Cabrini London Limited | Real estate | 2007 |
| Cabrini Management Ltd | Real estate | 2010 |
| Cafe & Coffee Ltd | Hospitality | 2022 |
| Cafe Compass Ltd | Hospitality | 2024 |
| Cafe Lumiere Ltd | Hospitality | 2024 |
| Cafenetics (UK) Limited | Hospitality | 2017 |
| Cahill Productions Limited | Administrative & support | 2020 |
| Cal's Cars Ltd | Wholesale & retail | 2016 |
| Calben Construction Limited | Construction | 2002 |
| Calben Scaffolding Limited | Extraterritorial | 2013 |
| Calce Interiors Ltd | Construction | 2026 |
| Calgiary UK Limited | Information & communication | 2025 |
| Calibria Ltd | Wholesale & retail | 2007 |
| Calming Minds Clinic Ltd | Health & social care | 2025 |
| Calverley Economic Advisors UK Limited | Professional & scientific | 2016 |
| Cambridge Cybersecurity Initiative Limited | Information & communication | 2020 |
| Cambridge Research Systems Limited | Manufacturing | 1989 |
| Cameron Brickwork Limited | Construction | 2026 |
| Cameron Hill Accountancy Limited | Professional & scientific | 2024 |
| Camilo Hvac Ltd | Construction | 2025 |
| Camphoto Limited | Professional & scientific | 2015 |
| Camulock Engineering Ltd | Information & communication | 2023 |
| Candcfees Limited | Administrative & support | 2009 |
| Candela Investment Holding Company S.A. | | 1999 |
| Candsteph Family Partnership LLP | | 2021 |
| Canine Paws Academy Ltd | Other services | 2024 |
| Cannon & Cass Ltd | Extraterritorial | 2017 |
| Cannuba Holdings Limited | Health & social care | 2019 |
| Canoports UK Limited | Manufacturing | 2013 |
| Canopy Investments Limited | Professional & scientific | 2019 |
| Canterbury Roofing Supplies Ltd | Construction | 2018 |
| Capable Construction Ltd | Construction | 2021 |
| Capital Assure Holdings Ltd | Real estate | 2025 |
| Capital Assure Ltd | Financial services | 2021 |
| Capital Instinct Ltd | Real estate | 2021 |
| Capitalsmart Solutions Ltd | Professional & scientific | 2025 |
| Capitol Accountancy Ltd | Professional & scientific | 2001 |
| Capk Holdings Ltd | Financial services | 2026 |
| Capri Luxury Tanning Ltd | Other services | 2026 |
| Capricorn Catering Limited | Hospitality | 2023 |
| Capstone Helpers Limited | Health & social care | 2022 |
| Capturing Castles Limited | Wholesale & retail | 2022 |
| Caraldane Trustees Limited | Other services | 2023 |
| Carat Consult Ltd | Information & communication | 2018 |
| Carbon Interiors Ltd | Construction | 2020 |
| Carbon Smart Ltd | Professional & scientific | 2024 |
| Cardamon Club Rochester Ltd | Hospitality | 2013 |
| Cardos Plastering Ltd | Construction | 2018 |
| Carduelis Solutions Limited | Professional & scientific | 2022 |
| Care Infinity Solutions Limited | Administrative & support | 2023 |
| Carers First | Health & social care | 2001 |
| Carey Property Development Ltd | Construction | 2013 |
| Carlo Kitchen Limited | Hospitality | 2024 |
| Carnell Investment Partners LLP | | 2024 |
| Carnell Property Partners Limited | Real estate | 2015 |
| Carpet Sale Centre Ltd | Wholesale & retail | 2017 |
| Carr Electrical Services Limited | Construction | 2010 |
| Carter Bonner & Co Limited | Professional & scientific | 2025 |
| CAS Property Rentals Ltd | Real estate | 2025 |
| Case Electrical Contractors Limited | Energy | 2014 |
| Cash for Vintage Ltd | Wholesale & retail | 2025 |