| Curryphoria Ltd | Hospitality | 2025 |
| Curve IT Infrastructures Limited | Information & communication | 2016 |
| Curved Air Ltd | Real estate | 2011 |
| Curzi Carpentry Limited | Construction | 2026 |
| Custom Housing Limited | Real estate | 2022 |
| CUT and Fade Limited | Other services | 2026 |
| CUT Blossom Investments Ltd | Real estate | 2019 |
| Cute Cat Ltd | Wholesale & retail | 2024 |
| Cutlass Care Services Ltd | Health & social care | 2022 |
| Cutlass Cars Limited | Transport & logistics | 2021 |
| Cutlass Group Ltd | Hospitality | 2018 |
| Cutlass Learning Academy Limited | Education | 2020 |
| Cutterham Homes Ltd | Real estate | 2026 |
| Cutting-Edge Therapeutics Ltd | Professional & scientific | 2016 |
| CV Drylining Ltd | Construction | 2026 |
| CV Plumbing & Heating Solutions Ltd | Construction | 2025 |
| CV1 Property Limited | Real estate | 2025 |
| CV3 25 Limited | Real estate | 2025 |
| CVA Drylining Ltd | Construction | 2025 |
| CVS by Motorexe Ltd | Wholesale & retail | 2025 |
| CVS Consultancy Ltd | Real estate | 2020 |
| CVS Super Store Ltd | Wholesale & retail | 2017 |
| CWA Consultants Limited | Professional & scientific | 2013 |
| CWF London Limited | Other services | 2021 |
| CWI Summits Limited | Administrative & support | 2023 |
| Cwsq (Uxbridge) Limited | Real estate | 2019 |
| Cwsq 6 (Streatham) Limited | Real estate | 2020 |
| Cwsq Freehold Limited | Real estate | 2019 |
| CWSQ1 Ltd | Real estate | 2017 |
| CWSQ3 Ltd | Real estate | 2018 |
| CWSQ4 Limited | Real estate | 2018 |
| CWW Logistics Ltd | Transport & logistics | 2019 |
| Cyanroad Ltd | Wholesale & retail | 2025 |
| Cyber Nest Ltd | Information & communication | 2023 |
| Cyber Protection Group Ltd | Information & communication | 2023 |
| Cyber Triangle Limited | Information & communication | 2022 |
| Cyberdev Limited | Construction | 2024 |
| Cyberhouselondon Ltd | Information & communication | 2024 |
| Cybernest AI Limited | Information & communication | 2025 |
| Cybernet Solutions Limited | Wholesale & retail | 2024 |
| Cybersecurix Global Limited | Professional & scientific | 2016 |
| Cybersort Ltd | Information & communication | 2023 |
| Cyberspark Solutions Ltd | Wholesale & retail | 2020 |
| Cybersrc Consultancy Limited | Administrative & support | 2019 |
| Cybtecs Limited | Information & communication | 2023 |
| Cyclex Limited | Wholesale & retail | 2024 |
| CYCLING4YOU Ltd | Education | 2018 |
| Cyclone Investments Group and Holdings Ltd | Real estate | 2022 |
| Cygnus a Limited | Real estate | 2012 |
| Cygnus Engineering Ltd | Professional & scientific | 2023 |
| Cyme Properties Limited | Real estate | 2011 |
| Cyna Court (Freehold) Limited | Households | 2000 |
| Cynergy Resources International Ltd | Wholesale & retail | 2023 |
| Cyntrek Solutions PVT Ltd | Information & communication | 2025 |
| Cypher Block Edge Ltd | Financial services | 2025 |
| Cypher Electronics Ltd | Wholesale & retail | 2019 |
| Cypherforums Ltd | Information & communication | 2025 |
| Cyprus Cars Ltd | Transport & logistics | 2015 |
| Cyps Digital Ltd | Information & communication | 2025 |
| Cyril Investment Agents Limited | Real estate | 2026 |
| Cyrus Cars Ltd | Construction | 2018 |
| Cytochrome Ltd | Professional & scientific | 2013 |
| CZ Management Ltd | Real estate | 2014 |
| D & D Contractors Limited | Construction | 2007 |
| D & H Fashions Ltd | Wholesale & retail | 2010 |
| D & H Local Stores Ltd | Wholesale & retail | 2023 |
| D & J Properties Management and Investments Ltd | Real estate | 2018 |
| D & R Building Contracts Limited | Construction | 2019 |
| D & S Interiors Limited | Manufacturing | 2019 |
| D a Georgiev Ltd | Construction | 2017 |
| D and T Plastering Services Ltd | Construction | 2015 |
| D Bolly Dance Company Ltd | Education | 2025 |
| D C White Limited | Wholesale & retail | 2010 |
| D Company Properties Ltd | Real estate | 2021 |
| D D Caterers Ltd | Hospitality | 2019 |
| D Davis Ltd | Real estate | 2019 |
| D Hurt Contracts Limited | Construction | 2006 |
| D I M Builder Ltd | Construction | 2020 |
| D J K Investments Ltd | Hospitality | 2014 |
| D M Sidhu Ltd | Construction | 2024 |
| D N Construction Services Limited | Construction | 2023 |
| D Nunan Carpentry & Joinery Limited | Construction | 2017 |
| D O'Connell Properties Limited | Real estate | 2004 |
| D O'Keefe Limited | Water & waste | 2019 |
| D Patel Associates Ltd | Professional & scientific | 2010 |
| D R Security & Electrical Ltd | Administrative & support | 1988 |
| D R Shop Ltd | Wholesale & retail | 2020 |
| D S Construction (UK) Limited | Construction | 2008 |
| D S Construction Plant Ltd | Extraterritorial | 2012 |
| D S P Accounting Services Limited | Professional & scientific | 2015 |
| D Stone Limited | Construction | 2024 |
| D&A Capital Management Ltd | Real estate | 2026 |
| D&A Cleaning Limited | Administrative & support | 2025 |
| D&A Refurbishment Ltd | Construction | 2026 |
| D&B Accountancy Limited | Professional & scientific | 2012 |
| D&D House Ltd | Construction | 2022 |
| D&G Quality Ltd | Construction | 2021 |
| D&G Security Services Ltd | Administrative & support | 2023 |
| D&I Installations Ltd | Construction | 2018 |
| D&I Recruitment Limited | Administrative & support | 2016 |