| Creative Developments Properties Limited | Construction | 2022 |
| Creative Sauce Ltd | Wholesale & retail | 2020 |
| Creatives Inc. (UK) Limited | Arts & recreation | 2007 |
| Crew Grooming Club Ltd | Other services | 2020 |
| Crew Isleworth Ltd | Other services | 2025 |
| Crew Richmond Ltd | Other services | 2025 |
| Crew Space Ltd | Other services | 2022 |
| Cris Rapid Transport Ltd | Transport & logistics | 2025 |
| CRM Plumbing Services Ltd | Construction | 2020 |
| Croitoru Trading Ltd | Wholesale & retail | 2019 |
| Crossroads Music Ltd | Education | 2025 |
| Crown Street Development Limited | Construction | 2020 |
| CS Accountancy Limited | Professional & scientific | 2015 |
| CSC Planning Limited | Professional & scientific | 2014 |
| CSG Developments Ltd | Real estate | 2025 |
| CSG Partners Properties Limited | Real estate | 2021 |
| CSM Design Ltd | Construction | 2022 |
| Ctec Services Ltd | Real estate | 2017 |
| CTP Associates Limited | Health & social care | 2012 |
| Cubik Solutions Ltd | Education | 2021 |
| Cuckoo Construction Ltd | Construction | 2014 |
| Cuckoo Interior Ltd | Professional & scientific | 2021 |
| Culinary Experience Ltd | Hospitality | 2025 |
| Cultural Dynamics Strategy & Marketing Limited | Professional & scientific | 2003 |
| Curiouser Insights Ltd | Professional & scientific | 2018 |
| Currant Communications Limited | Professional & scientific | 2014 |
| Customlighting Limited | Information & communication | 2023 |
| Cute Kiddos Limited | Wholesale & retail | 2024 |
| Cuts and Runs Ltd | Other services | 2025 |
| CVN Properties Limited | Real estate | 2025 |
| Cyber Execs Ltd | Administrative & support | 2016 |
| Cyber Systems International Solutions Limited | Information & communication | 2026 |
| Cygnus X Limited | Real estate | 2017 |
| Cymru International Limited | Information & communication | 2005 |
| Cynapses.Ai Limited | Information & communication | 2021 |
| Céleste Design Ltd | Professional & scientific | 2023 |
| D K Doctors Limited | Health & social care | 2012 |
| D&D Capital Ltd | Wholesale & retail | 2013 |
| D&I Contractors Limited | Construction | 2020 |
| D&I Group Limited | Financial services | 2020 |
| D&J Malhi Ltd | Transport & logistics | 2021 |
| D3 Esports Solutions Ltd | Professional & scientific | 2024 |
| Daisy CL Limited | Other services | 2014 |
| Damian Plastering Rendering Ltd | Construction | 2024 |
| DAN Shop Ltd | Hospitality | 2024 |
| DAN Street Ltd | Hospitality | 2019 |
| Dana House Limited | Information & communication | 2026 |
| Danasel Delivery Limited | Transport & logistics | 2023 |
| Dancesport UK Limited | Arts & recreation | 2000 |
| Danjo Consulting Limited | Professional & scientific | 2018 |
| Dannyopia Enterprises Limited | Real estate | 2025 |
| Danson Corporate Ltd | Information & communication | 2025 |
| Danstrad Limited | Information & communication | 2016 |
| Danto Street Food Ltd | Hospitality | 2021 |
| Dany Handyman Ltd | Construction | 2020 |
| Danzee Solutions Limited | Information & communication | 2010 |
| Daoud Alghuti Ltd | Transport & logistics | 2023 |
| DARE2LEAD Ltd. | Other services | 2012 |
| Darkntoon Ltd | Wholesale & retail | 2023 |
| Data Intellect Limited | Information & communication | 2012 |
| Datam Ltd | Information & communication | 2023 |
| Datchet LMM Limited | Education | 2019 |
| Datta Engineering Limited | Administrative & support | 2012 |
| Davi Maintenance & Management Solutions Ltd | Construction | 2024 |
| David Mace Associates Ltd | Other services | 2016 |
| Davies Walk Residents Company Limited | Households | 1998 |
| Davis Graphic Services Limited | Manufacturing | 1994 |
| DB Associates Ltd | Professional & scientific | 2017 |
| DB Services (Greenford) Ltd | Construction | 2002 |
| DC Installations Ltd | Construction | 2025 |
| DDS Properties Ltd | Real estate | 2024 |
| DE Ranchev Ltd | Transport & logistics | 2020 |
| De&Nezaj Constructions Ltd | Construction | 2017 |
| Debala Ltd | Other services | 2024 |
| Deco Global Investments Ltd | Real estate | 2014 |
| Decor House Construction Ltd | Construction | 2018 |
| Dedalo Ltd | Information & communication | 2010 |
| Dedeepya IT Solutions Ltd | Information & communication | 2016 |
| Deep Food & Wine PVT Ltd | Wholesale & retail | 2020 |
| Deepcore Ltd | Information & communication | 2019 |
| Deepdive Solutions Limited | Information & communication | 2021 |
| Defig Play Ltd | Information & communication | 2025 |
| Deism IT Solutions Ltd | Wholesale & retail | 2013 |
| Deliberately Ltd | Manufacturing | 2018 |
| Delta Financial Services Limited | Financial services | 2009 |
| Deluxe Car Services Ltd | Transport & logistics | 2020 |
| Denticity Ltd | Health & social care | 2026 |
| Dermopolis Ltd | Health & social care | 2024 |
| Design Apps Ltd. | Information & communication | 2015 |
| Desserts Hub Ltd | Hospitality | 2022 |
| Desserts Spot Ltd | Hospitality | 2025 |
| Devoir Developments LLP | | 2020 |
| Dewar Stuart Associates Limited | Professional & scientific | 2011 |
| DF Haulage Ltd | Transport & logistics | 2025 |
| DH Drainage Power Ltd | Water & waste | 2026 |
| Dhani XR Ecosystems Limited | Professional & scientific | 2026 |
| Dhani XR Holdings Limited | Financial services | 2026 |
| Dharameen Ltd | Transport & logistics | 2023 |
| DHB Advisory Ltd | Professional & scientific | 2025 |
| DHI Ventures Limited | Wholesale & retail | 2026 |