| Crown Cars Banbury Ltd | Transport & logistics | 2025 |
| Crown Harbor Ltd | Wholesale & retail | 2026 |
| Crown House Banbury Limited | Construction | 2015 |
| Crown Maintenance Ltd | Agriculture & fishing | 2025 |
| Crownlock Services Limited | Wholesale & retail | 2026 |
| CRS Delivery Limited | Transport & logistics | 2024 |
| Crumpled Leaf Limited | Extraterritorial | 2005 |
| Crystal Design & Build Ltd | Construction | 2022 |
| Crystal Intentions Ltd | Wholesale & retail | 2023 |
| Crystolutions Limited | Information & communication | 2005 |
| CTR Weymouth Ltd | Real estate | 2025 |
| Ctzn Limited | Professional & scientific | 2024 |
| Cubiculo Ltd | Administrative & support | 2012 |
| Cuggini Crystal Clean Ltd | Administrative & support | 2026 |
| Culgruff Ltd | Hospitality | 2023 |
| Culham Consulting Limited | Professional & scientific | 2021 |
| Culture Collaborators Ltd | Administrative & support | 2025 |
| Culture Stream Limited | Arts & recreation | 2020 |
| Cura Room Limited | Information & communication | 2022 |
| Curv Racing Simulators Limited | Manufacturing | 2020 |
| Customer 360 Limited | Professional & scientific | 2024 |
| Customer Excellence Limited | Professional & scientific | 2005 |
| Customer Health Check Ltd. | Professional & scientific | 2014 |
| CUT to the Point Ltd | Other services | 2025 |
| CW Properties Ltd | Real estate | 2020 |
| Cw&Ys Partners LLP | | 2023 |
| CWF Oxford Limited | Wholesale & retail | 2016 |
| Cwisehgv Limited | Transport & logistics | 2021 |
| CX Pharma Consulting Limited | Professional & scientific | 2020 |
| Cyber Fusion 3 Integrated Services Limited | Information & communication | 2022 |
| Cyber Fusion 3 Limited | Information & communication | 2017 |
| Cyber Security Evaluations Limited | Information & communication | 2020 |
| Cyber-Weld Holdings Limited | Professional & scientific | 2019 |
| Cyber-Weld Limited | Professional & scientific | 1990 |
| Cyber-Weld Systems Ltd | Professional & scientific | 2025 |
| Cycle Services Limited | Wholesale & retail | 2024 |
| Cycling Brands Limited | Wholesale & retail | 2015 |
| Cygnus Loop Technology Consulting Ltd | Other services | 2019 |
| CZM Courier Ltd | Transport & logistics | 2023 |
| D a Wright Farming Limited | Agriculture & fishing | 2012 |
| D Barry Plumbing & Heating Limited | Construction | 2019 |
| D D Racing Limited | Administrative & support | 2018 |
| D I M Designing Ltd | Construction | 2019 |
| D J Beak (SRC) Ltd | Construction | 2011 |
| D Leigh Heating & Plumbing Ltd | Construction | 2025 |
| D M J Bathrooms and Plumbing Ltd | Construction | 2016 |
| D Rose Electrical Ltd | Construction | 2023 |
| D Smith Consultant & Specialist Training Ltd | Professional & scientific | 2024 |
| D Whitton Construction Ltd | Construction | 2023 |
| D&B Cobilas Services Ltd | Construction | 2017 |
| D.D Global Solutions Ltd | Administrative & support | 2024 |
| D.Hill Construction Limited | Construction | 2014 |
| D.J. Farms Limited | Agriculture & fishing | 1989 |
| D.R Orbit Ltd | Transport & logistics | 2026 |
| D.S.A the Dental Scanning Academy Limited | Extraterritorial | 2025 |
| D.W.L. Limited | Transport & logistics | 1988 |
| D.Willshere Furniture Limited | Manufacturing | 2014 |
| D2T Multisport Ltd | Wholesale & retail | 2024 |
| D4 Developments (Stony) Ltd | Construction | 2011 |
| Dach Pubs Ltd | Hospitality | 2024 |
| Dadalto Software and Consultancy Ltd | Wholesale & retail | 2020 |
| Dadu Logistics Limited | Transport & logistics | 2018 |
| Daeda Consulting Limited | Professional & scientific | 2013 |
| Daenen Global Consultancy Limited | Professional & scientific | 2025 |
| Daisy Anna-Locke Ltd | Arts & recreation | 2025 |
| Dallamura Holdings Limited | Financial services | 2017 |
| Dallamura Limited | Wholesale & retail | 2014 |
| Dallas Keith Limited | Manufacturing | 1972 |
| Dalti Properties Limited | Real estate | 2023 |
| DAM Risk Assessments Ltd | Professional & scientific | 2025 |
| Damian PDW Ltd | Wholesale & retail | 2025 |
| DAN Manning Ltd | Administrative & support | 2020 |
| DAN19 Ltd | Transport & logistics | 2013 |
| Dana Point Capital Limited | Financial services | 2020 |
| Danbarr Ltd | Professional & scientific | 2007 |
| Dancing Pigeon Limited | Education | 2015 |
| Daniel Boys Bathrooms Limited | Construction | 2023 |
| Daniel Neal Digital Consultancy Ltd | Information & communication | 2016 |
| Danielle Gamage Ltd | Professional & scientific | 2025 |
| Danmedical Holdings Limited | Extraterritorial | 2025 |
| Danmedical Limited | Manufacturing | 2002 |
| Dannys Sports Bar and Grill Ltd | Hospitality | 2023 |
| DAR Lighting Limited | Wholesale & retail | 2004 |
| Dare Design Ltd | Professional & scientific | 2016 |
| Darideli Pizza Ltd | Hospitality | 2025 |
| Darkstar Property & Renovation Ltd | Real estate | 2025 |
| Dassett Forge Farriery Practice Ltd | Agriculture & fishing | 2014 |
| Daston Commercial Ltd | Professional & scientific | 2025 |
| Data & AI Tech Ltd | Information & communication | 2022 |
| Datacurated Ltd | Information & communication | 2021 |
| Datafixr Limited | Information & communication | 2026 |
| Datashield Security Ltd | Information & communication | 2018 |
| Datatron Limited | Information & communication | 1991 |
| Dave Rowley Broadcast Ltd | Information & communication | 2022 |
| Dave's Flame Ltd | Hospitality | 2025 |
| David Adkin Limited | Arts & recreation | 2012 |
| David Arkell Limited | Manufacturing | 2013 |
| David Bagnall Limited | Construction | 1999 |
| David Bostock Photography Ltd | Professional & scientific | 2002 |
| David Colegrave Group Limited | Extraterritorial | 2001 |