| Credit Corp UK Debt Solutions Limited | Administrative & support | 2013 |
| Crescent Music Productions Ltd | Education | 2026 |
| Crockerton Furniture Centre Limited | Administrative & support | 2008 |
| Cross Keys Farms Limited | Agriculture & fishing | 1990 |
| Crossbow Editorial Services Limited | Professional & scientific | 2004 |
| Crown Arbitrations Limited | Professional & scientific | 1990 |
| Crown Carpentry and Building Limited | Construction | 2023 |
| Crusoe Homes Limited | Construction | 2021 |
| CTS Interiors Limited | Construction | 2020 |
| Cuckoo Lane Coaching & Consulting Limited | Administrative & support | 2017 |
| CULTIV8 Ltd | Education | 2011 |
| Cultivating Community C.I.C. | Agriculture & fishing | 2019 |
| Cultured Labz Ltd | Wholesale & retail | 2025 |
| Cunningham & Associates Limited | Professional & scientific | 2020 |
| Curated Canvas Limited | Wholesale & retail | 2022 |
| Curious Brand Design Ltd | Professional & scientific | 2015 |
| Curious Ways Creative Limited | Information & communication | 2017 |
| Curtis Ilott Limited | Other services | 2024 |
| Curtis Ilott Memorials Limited | Manufacturing | 2017 |
| Cutting Zone Barbers Limited | Other services | 2025 |
| CWA Finance Limited | Extraterritorial | 2024 |
| Cyril Catering Limited | Hospitality | 2024 |
| Cyril Lettings Limited | Real estate | 2017 |
| D S Waterhouse Haulage Ltd | Transport & logistics | 2017 |
| D. J. Kelly Homes Limited | Construction | 1987 |
| D. J. Kelly Homes Properties Limited | Real estate | 2025 |
| D.A.R.E. to Transform Limited | Professional & scientific | 2026 |
| D.G. Plumbing Services Limited | Construction | 2012 |
| D.J. & B.A. Brooks Limited | Professional & scientific | 1961 |
| D.S. Phillips Limited | Wholesale & retail | 1980 |
| DA Brand Communications Ltd | Administrative & support | 2021 |
| Daaang Ltd | Professional & scientific | 2025 |
| Dairy Home Team Limited | Wholesale & retail | 2007 |
| Daka Light Limited | Administrative & support | 2012 |
| Dampsense Ltd | Professional & scientific | 2025 |
| Darren's Handyman Services Ltd | Construction | 2022 |
| Dart Financial Education Ltd | Administrative & support | 2025 |
| Dart Wealth Ltd | Professional & scientific | 2024 |
| Dave Francis Education Ltd | Education | 2013 |
| Dave Lucey Limited | Construction | 1999 |
| Dave White Plumbing & Heating Limited | Construction | 2002 |
| Davey Family Holdings Ltd | Extraterritorial | 2024 |
| David Hunt Agricultural Contractors Ltd | Agriculture & fishing | 2021 |
| David’S Beans Ltd | Wholesale & retail | 2024 |
| Davisventuresco Ltd | Financial services | 2025 |
| Dawn Scott Racehorse Transport Ltd | Transport & logistics | 2022 |
| Dbtronics Limited | Construction | 2025 |
| DC Supplies Ltd | Wholesale & retail | 2018 |
| DCL Construction Ltd | Administrative & support | 2024 |
| Dcode Limited | Manufacturing | 2005 |
| Dead Head Ltd | Wholesale & retail | 2019 |
| Deadly IS the Female Limited | Wholesale & retail | 2008 |
| Dean Flooring Ltd | Construction | 2014 |
| Deborah Schmid Limited | Financial services | 2022 |
| Deck and Dagger Games Ltd | Wholesale & retail | 2025 |
| Deckchair U.K. Limited | Professional & scientific | 1998 |
| Dedoctive Ltd | Information & communication | 2024 |
| Dennis Maps Limited | Manufacturing | 2014 |
| Denude Limited | Wholesale & retail | 2019 |
| Derek Miles Ltd | Wholesale & retail | 2003 |
| Design and Planning Works Ltd | Professional & scientific | 2022 |
| Design Crucible Ltd | Professional & scientific | 2014 |
| Designed Woodwork Limited | Manufacturing | 2018 |
| Development Total Solutions Limited | Construction | 2018 |
| Developmental Therapy Consultants Limited | Education | 1993 |
| Dexter Window Cleaning Limited | Administrative & support | 2021 |
| Dexy Digital Limited | Administrative & support | 2013 |
| DF Services Southwest Limited | Manufacturing | 2018 |
| DHA Energy Limited | Construction | 2025 |
| Diana Miller Planning and Highways Law Limited | Professional & scientific | 2025 |
| Diatomists Ltd | Wholesale & retail | 2020 |
| Diblighco Ltd | Professional & scientific | 2019 |
| Digigig Ltd | Professional & scientific | 2024 |
| Digital Creative Solutions Ltd | Information & communication | 2018 |
| Distinctive Communications Limited | Professional & scientific | 2022 |
| Diverse Futures Ltd | Education | 2023 |
| Divinity Florals Ltd | Wholesale & retail | 2022 |
| DK Analytics Limited | Professional & scientific | 2007 |
| DKP (Bristol) Ltd | Wholesale & retail | 2018 |
| Dlhm Limited | Construction | 2010 |
| DMD Consulting Limited | Professional & scientific | 2015 |
| DMO Framing Ltd | Construction | 2025 |
| DNA Family Limited | Extraterritorial | 2023 |
| DNA Legal Limited | Professional & scientific | 2006 |
| DNA Workplace Limited | Professional & scientific | 2017 |
| DNA Worldwide Group Holdings Limited | Financial services | 2023 |
| DNA Worldwide Group Ltd | Professional & scientific | 2004 |
| Dobyn Ltd | Real estate | 2022 |
| DOE and Smith Ltd. | Administrative & support | 2019 |
| Dolphin House Residents Limited | Households | 1988 |
| Dominic Malone Limited | Health & social care | 2010 |
| Doodles and Scribbles Limited | Information & communication | 2017 |
| Dore & Rees Auction House Ltd | Wholesale & retail | 2021 |
| DOS Landscapes Ltd | Administrative & support | 2024 |
| Dough&Co Frome Limited | Hospitality | 2021 |
| Downtown Productions London Limited | Arts & recreation | 2024 |
| DR Boyd-Carson Ltd | Health & social care | 2024 |
| DR Henry Matson Limited | Health & social care | 2021 |
| Dragon Code Limited | Information & communication | 2024 |
| Dranshaw Limited | Wholesale & retail | 1982 |