| D-Fence Ltd | Information & communication | 2001 |
| D. L. Mills Ltd | Agriculture & fishing | 2007 |
| D.A.S Bound Estates Limited | Real estate | 2020 |
| D.B.S Brickwork Ltd | Construction | 2019 |
| D.G.R. Group Limited | Information & communication | 2007 |
| D.I.S. Limited | Construction | 1988 |
| D.J.G Builders Limited | Construction | 2021 |
| D.P. Rollings Limited | Administrative & support | 2004 |
| D2M Innovation Limited | Professional & scientific | 2010 |
| D2SMART Projects Limited | Construction | 2014 |
| D:Uk Limited | Administrative & support | 2004 |
| DA Associates Consultancy Limited | Professional & scientific | 2019 |
| Dabaro Limited | Wholesale & retail | 2012 |
| DAC Design Services Limited | Professional & scientific | 2023 |
| DAC Power Limited | Administrative & support | 2013 |
| DAC Resources Limited | Administrative & support | 2026 |
| Dadson Software Limited | Extraterritorial | 2012 |
| Daedal Ventures Ltd | Professional & scientific | 2025 |
| Daffodil Support Services Ltd | Health & social care | 2015 |
| Daines Bess Limited | Energy | 2022 |
| Daines Flexpower Ltd | Energy | 2024 |
| Daines Green NG Limited | Financial services | 2022 |
| Dair Limited | Professional & scientific | 2003 |
| Dair Sport Limited | Professional & scientific | 2003 |
| Daisy and Delilah Ltd. | Wholesale & retail | 2013 |
| Daisybank Community Interest Company | Arts & recreation | 2025 |
| Dalel Consulting Ltd | Other services | 2023 |
| Dallison Contracting Limited | Construction | 2024 |
| Dalton Computer Services Limited | Information & communication | 2000 |
| Damar Catering Limited | | 1980 |
| Damerosehay Land Holdings Limited | Professional & scientific | 1986 |
| Damsons Trading Company Ltd | Wholesale & retail | 2021 |
| DAN Abrahams Sport Psychology Limited | Other services | 2016 |
| DAN Clep Structural Design Limited | Other services | 2025 |
| DAN Wheels Limited | Transport & logistics | 2022 |
| Dance 2000 | | 1997 |
| Dance Balance Limited | Arts & recreation | 2022 |
| Dance Balboa Ltd | Arts & recreation | 2015 |
| Dancer Property Limited | Real estate | 2022 |
| Danelaw Ltd | Wholesale & retail | 2010 |
| Danford Investments Limited | Real estate | 2025 |
| Dangerous Goods Consultancy Services Ltd | Professional & scientific | 2020 |
| Danica Cleaning and Maintenance Services Limited | Administrative & support | 2020 |
| Daniel Deacon Developments Limited | Extraterritorial | 2025 |
| Daniel Wilson & Associates Ltd | Professional & scientific | 2021 |
| Daniela Hanková Limited | Extraterritorial | 2024 |
| Daniels & Daniels (Consultants) Ltd | Professional & scientific | 2011 |
| Danmarbuild Ltd | Construction | 2022 |
| Danson (Glos) Limited | Construction | 2016 |
| Danter Event Group Ltd | Administrative & support | 2022 |
| Danter Leisure Group Ltd | Administrative & support | 2026 |
| Danuka Ltd | Transport & logistics | 2024 |
| Darby Legacy Park Homes Ltd | Manufacturing | 2025 |
| Darcourts Ltd | Wholesale & retail | 2012 |
| Darcy's Creperie Limited | Hospitality | 2024 |
| Dargan Child Care Limited | Education | 2001 |
| Darilmaz Catering Ltd | Hospitality | 2023 |
| Darlington Cars Limited | Wholesale & retail | 2025 |
| Dart Recruitment Limited | Administrative & support | 1999 |
| Dart Vale Dental Care Limited | Health & social care | 2008 |
| Darwin Future Ltd | Information & communication | 2022 |
| Dash Couriers Ltd | Transport & logistics | 2025 |
| Data Centre Spares Limited | Wholesale & retail | 2024 |
| Data Leaf Bidco Limited | Financial services | 2024 |
| Data Theorem Ltd | Information & communication | 2022 |
| Database Tech Solutions Limited | Professional & scientific | 2024 |
| Datadai Ltd | Administrative & support | 2026 |
| Dataform Ltd | Manufacturing | 2006 |
| Datapol Consultants Limited | Real estate | 2008 |
| Datasource Computer Employment Limited | Administrative & support | 1982 |
| Datasource Employment Holdings Limited | Financial services | 2010 |
| Datasource Recruitment Limited | Administrative & support | 2011 |
| Datum Survey Services Limited | Administrative & support | 2004 |
| Dauntless Services Ltd | Professional & scientific | 2023 |
| DAV Group Ltd | Wholesale & retail | 2023 |
| Davalt Investments Ltd | Financial services | 2022 |
| Davcaps Limited | Wholesale & retail | 2001 |
| Dave Payne Electricians Ltd | Construction | 2013 |
| Dave Reeves Ltd | Construction | 2015 |
| Davey & Vanheerden Ltd | Construction | 2021 |
| David Andrews Fitness Ltd | Arts & recreation | 2010 |
| David Bridgwater Racing LLP | | 2007 |
| David Deacon Builders Limited | Construction | 2019 |
| David Greening Limited | Construction | 1987 |
| David H Heath Limited | Professional & scientific | 2007 |
| David Hall Stonemasonry Limited | Construction | 2012 |
| David Henderson Consultancy Limited | Professional & scientific | 2022 |
| David Jago Ltd | Other services | 2001 |
| David John Barbershop Limited | Other services | 2018 |
| David Mason Heating and Plumbing Limited | Construction | 2013 |
| David O'Shea Carpentry Ltd | Manufacturing | 2026 |
| David Partridge Limited | Professional & scientific | 2017 |
| David Reach 100 PR Ltd | Information & communication | 2020 |
| David Short Transport Limited | Transport & logistics | 2003 |
| David Stevenson Estates Ltd | Real estate | 2025 |
| Davidcrawfordconsulting Ltd | Professional & scientific | 2025 |
| Davidjamesnelson Ltd | Real estate | 2026 |
| Davies Dental Ltd | Health & social care | 2025 |
| Davies Property (Cornwall) Ltd | Real estate | 2025 |
| Davis Gregory Limited | Professional & scientific | 2003 |