| C Gheorghita Ltd | Construction | 2014 |
| C J Management and Services Limited | Professional & scientific | 2017 |
| C Three Creative Limited | Professional & scientific | 2025 |
| C Three Studios Limited | Professional & scientific | 2019 |
| C&A Barbers Limited | Other services | 2025 |
| C&A Concrete Ltd | Construction | 2024 |
| C&E Drywall Limited | Construction | 2020 |
| C&F Logistics Limited | Construction | 2015 |
| C&L Patterson Control Systems Ltd | Professional & scientific | 2014 |
| C&S Decorating Ltd | Construction | 2022 |
| C.F&P.Construction Ltd | Construction | 2020 |
| C.M.20 Plumbing Ltd | Construction | 2025 |
| C.P.Impex Limited | Wholesale & retail | 2025 |
| CAB Fleet Ltd | Transport & logistics | 2026 |
| Cable Realty Limited | Real estate | 2021 |
| Cabot Company Limited | Manufacturing | 1972 |
| CAD Fusion Limited | Professional & scientific | 2019 |
| Caenby Corner Transport Limited | Transport & logistics | 2015 |
| Caffco Limited | Administrative & support | 2012 |
| Caffcon Limited | Construction | 2023 |
| Caffe Venezia Limited | Hospitality | 2007 |
| Caffe Yonii Limited | Administrative & support | 2017 |
| Cafferty Construction (UK) Limited | Construction | 2012 |
| Cafferty Construction Holdings Limited | Professional & scientific | 2017 |
| Cafferty Construction Limited | Construction | 2003 |
| Cafit Ltd | Information & communication | 2020 |
| Caif Ltd | Construction | 2025 |
| Cain Infrastructure Ltd | Professional & scientific | 2025 |
| Caireen Ltd | Professional & scientific | 2023 |
| Cakes by Aida Limited | Wholesale & retail | 2017 |
| Calamansi Limited | Information & communication | 2018 |
| Calbrin Limited | Professional & scientific | 2025 |
| Calbury Limited | Professional & scientific | 2024 |
| Calcutta Road Management Company Limited | Real estate | 2025 |
| Caldermere Limited | Professional & scientific | 2025 |
| Caledfwlch Ltd | Other services | 2020 |
| Calheath Limited | Professional & scientific | 2026 |
| Calipro Advisors Ltd | Professional & scientific | 2024 |
| Call of FIX Ltd | Construction | 2025 |
| Callistus UK Limited | Wholesale & retail | 2017 |
| Calmer Chameleon Holistic Therapies Limited | Health & social care | 2026 |
| Calvados Property Management Ltd | Real estate | 2018 |
| Calvionyx Estates Limited | Real estate | 2026 |
| Calvionyx Holdings Limited | Financial services | 2026 |
| CAM Ceylon Ltd | Arts & recreation | 2025 |
| Caman (Ealing) Limited | Real estate | 2020 |
| Caman (Wembley) Limited | Real estate | 2018 |
| Camaron Arlequin Ltd | Professional & scientific | 2017 |
| Camata Properties Limited | Real estate | 2016 |
| Camberley Limited | Real estate | 2025 |
| Cambridge Housing Ltd | Real estate | 2024 |
| Cambridge Roofing & Scaffolding Ltd | Construction | 2019 |
| Cambrin Limited | Professional & scientific | 2025 |
| Camden Clothes Ltd | Wholesale & retail | 2026 |
| Camden EYE Ltd | Wholesale & retail | 2024 |
| Camden Glorious UK Ltd | Wholesale & retail | 2026 |
| Camden LUX Ltd | Wholesale & retail | 2025 |
| Camdenwell Ltd | Hospitality | 2013 |
| Camel Investments Limited | Real estate | 2020 |
| Cameron Film Limited | Professional & scientific | 2003 |
| Camk Construction Ltd | Construction | 2025 |
| Camp Hill Holdings Limited | Financial services | 2021 |
| Camp Hill Investments Limited | Financial services | 2021 |
| Campanelle Ltd | Hospitality | 2024 |
| Campos Dental Clinic Ltd | Health & social care | 2017 |
| Camrose Estates Ltd | Real estate | 2022 |
| CAN Property Agents Limited | Real estate | 2021 |
| Canarycrown Investments Limited | Real estate | 2011 |
| Canarycrown Limited | Real estate | 1992 |
| Candycats Pets Ltd | Wholesale & retail | 2023 |
| Cannon Associates Limited | Professional & scientific | 1988 |
| Cannon Mini Market Ltd | Wholesale & retail | 2022 |
| Cannon Motor Engineering Ltd | Wholesale & retail | 2026 |
| Cannon's Corner Food & Wine Limited | Wholesale & retail | 2021 |
| Canon Cafe UK Ltd | Hospitality | 2023 |
| Canons High School | Education | 2011 |
| Canons Investments Limited | Real estate | 2017 |
| Canons Park Consulting Limited | Education | 2018 |
| Canons Park Service Centre Ltd | Wholesale & retail | 2024 |
| Canons Transport Limited | Transport & logistics | 2017 |
| Canpoi Limited | Information & communication | 2018 |
| Canto Corvino Limited | Hospitality | 2014 |
| Canvas Capital Ltd | Real estate | 2023 |
| Canvas Print Studio Limited | Other services | 2015 |
| Canvasbay Limited | Wholesale & retail | 1987 |
| CAP Takeaway Limited | Hospitality | 2025 |
| Capeworld Limited | Hospitality | 1993 |
| Capex Trade Ltd | Wholesale & retail | 2023 |
| Capital Advisory & Consultancy Ltd | Wholesale & retail | 2025 |
| Capital Advisory Limited | Professional & scientific | 2015 |
| Capital Basement Solutions Limited | Construction | 2026 |
| Capital Care Wealth Management Ltd | Administrative & support | 2017 |
| Capital Maker Limited | Real estate | 2004 |
| Capitique Financial Limited | Financial services | 2020 |
| Capitique IP Limited | Information & communication | 2020 |
| Capper Street Capital Holdings Limited | Construction | 2019 |
| Capper Street Capital Investments Limited | Construction | 2019 |
| Captured by Corinne Ltd | Professional & scientific | 2022 |
| Capwise Ltd | Financial services | 2008 |
| Car House London Limited | Wholesale & retail | 2024 |