| Coulton Export Ltd | Extraterritorial | 2014 |
| Covers by LEE Rosete Ltd | Arts & recreation | 2025 |
| Craig Chapman Financial Planning Ltd | Financial services | 2012 |
| Cranemoor Ltd | Administrative & support | 2019 |
| Crescotech Limited | Information & communication | 2013 |
| Crest New Homes Ltd | Construction | 2017 |
| Crested Crane Connections UK Ltd | Professional & scientific | 2019 |
| Crofton Developments Limited | Construction | 1998 |
| Crossley Kitchens Ltd | Construction | 2005 |
| Crystalline Shine Ltd | Other services | 2019 |
| CSE Bournemouth Limited | Transport & logistics | 1980 |
| CSN Prestige & Performance Limited | Wholesale & retail | 2020 |
| CSR Breakdown and Recovery Limited | Transport & logistics | 2016 |
| CSW Accounting Ltd | Professional & scientific | 2026 |
| Cubit Studios Limited | Information & communication | 2013 |
| Cullt Movie Ltd | Information & communication | 2025 |
| Cura AI Limited | Information & communication | 2026 |
| Curtiss-Wright Controls (UK) Finance Co., Limited | Financial services | 2024 |
| Curtiss-Wright Controls (UK) Holding Co., Limited | Financial services | 2024 |
| Curtiss-Wright Controls (UK) Limited | Manufacturing | 2002 |
| Curtiss-Wright Flow Control (UK) Limited | Manufacturing | 2001 |
| Custom Linings Limited | Wholesale & retail | 2009 |
| Custom Rubber Stamp Ltd | Manufacturing | 2013 |
| Cuzco Flooring Ltd | Wholesale & retail | 2023 |
| CW Construction (Dorset) Limited | Construction | 2023 |
| Cyberpig Ltd | Information & communication | 2024 |
| D a Plastics Holdings Limited | Real estate | 2015 |
| D I Buy Ltd | Wholesale & retail | 2020 |
| D Mcneill Limited | Professional & scientific | 2016 |
| D S Partitioning Limited | Construction | 2003 |
| D S Sheet Metal Limited | Manufacturing | 2004 |
| D&C Groundworks & Civils Ltd | Construction | 2024 |
| D.A. Renovations Ltd | Construction | 2022 |
| D.S. 2000 Limited | Administrative & support | 1999 |
| D.Stewart & SON, Limited | Agriculture & fishing | 1916 |
| Dacos Design Limited | Professional & scientific | 2005 |
| Dalton & Ealing Brickwork Limited | Construction | 2014 |
| DAN White Cars Ltd | Transport & logistics | 2021 |
| Dancezb Limited | Arts & recreation | 2020 |
| Daneswood Accounting Limited | Professional & scientific | 2017 |
| Dans Vehicle Solutions Car and Commercial Ltd | Wholesale & retail | 2023 |
| Daramac Ltd | Information & communication | 2021 |
| Database Applications Training & Associated Services Limited | Information & communication | 1993 |
| Dataplan Ltd | Information & communication | 2012 |
| Dave Forrest Transport Limited | Transport & logistics | 2007 |
| David Lewis Electrical Contractors Limited | Construction | 2015 |
| David Mooney Cleaning Ltd | Administrative & support | 2014 |
| Davies Chiropractic & Sports Therapy Ltd | Health & social care | 2012 |
| Davis Global Ltd | Wholesale & retail | 2022 |
| Day and Sons Ltd | Real estate | 2022 |
| Dayeh Commercial Projects Limited | Real estate | 1990 |
| DC (Sopley) Ltd | Professional & scientific | 2016 |
| DE Luca Associates Limited | Professional & scientific | 2006 |
| DE Pearle Productions Limited | Arts & recreation | 2001 |
| Dearlove Holdings Limited | Construction | 2017 |
| Debs Care Ltd | Health & social care | 2022 |
| Deep Time Films Ltd | Information & communication | 2022 |
| Defence Aero Ltd | Wholesale & retail | 2010 |
| Delphara Limited | Information & communication | 2026 |
| Delta Power Group Holdings Ltd | Financial services | 2023 |
| Delta Power Management Services Ltd | Professional & scientific | 2007 |
| Denisons Estate Agents Limited | Real estate | 2010 |
| Dentless Limited | Wholesale & retail | 2015 |
| Dentz Paint and Body Limited | Wholesale & retail | 2017 |
| Derritt Limited | Real estate | 2018 |
| Design & Build Group Ltd | Construction | 2019 |
| Design Fire & Security Ltd | Manufacturing | 2017 |
| Desmil (Management) Limited | Households | 1968 |
| Deval Limited | Manufacturing | 1986 |
| Devready Ltd | Information & communication | 2024 |
| Dewberry Properties Ltd | Real estate | 2021 |
| DG Drinks Ltd | Manufacturing | 2023 |
| DG Marine Ltd | Other services | 2018 |
| DGB Coaching Ltd | Education | 2025 |
| Diamond Sporting Group Limited | Financial services | 2011 |
| Diamond Sports Events Limited | Extraterritorial | 2007 |
| Diamondz & Alloyz Ltd | Wholesale & retail | 2017 |
| Digital Heritage SDS IA Group Ltd | Administrative & support | 2016 |
| DII (Group) Ltd | Information & communication | 2018 |
| DII Ltd | Administrative & support | 2018 |
| Diji Consultancy Ltd | Professional & scientific | 2025 |
| Dine-In-Leisure Ltd | Hospitality | 2020 |
| Dinggly Limited | Information & communication | 2011 |
| Direct Logistics Express Ltd | Transport & logistics | 2025 |
| Direct Offers Limited | Wholesale & retail | 1996 |
| Dirty Gerties Ltd | Hospitality | 2021 |
| Discover Architecture Ltd | Professional & scientific | 2024 |
| Discover the Better Ltd | Wholesale & retail | 2022 |
| Discovery Village Ltd | Arts & recreation | 2023 |
| Displays by Jade Limited | Wholesale & retail | 2025 |
| Dive South Ltd | Arts & recreation | 2008 |
| DJ Lewis Contracting Ltd | Construction | 2024 |
| DJB Cards Ltd | Wholesale & retail | 2023 |
| Dmsco Limited | Wholesale & retail | 2021 |
| DMV Trading Ltd | Wholesale & retail | 2020 |
| DMW Glazing Repairs Ltd | Construction | 2020 |
| DMW Windows & Doors Ltd | Construction | 2018 |
| Dockhead Holdings Limited | Real estate | 1965 |
| Dockland Brickwork Ltd | Construction | 2022 |
| Dogs Dogs Dogs Ltd | Wholesale & retail | 2026 |