| D & N Maintenance Limited | Construction | 2016 |
| D & T Models Ltd Ltd | Wholesale & retail | 2009 |
| D B L Software Limited | Information & communication | 1998 |
| D Blencowe Scaffolding Limited | Construction | 2026 |
| D C Search Limited | Administrative & support | 2015 |
| D H Cabling Limited | Construction | 2019 |
| D H Electronics Ltd | Manufacturing | 2018 |
| D Loughrey Consulting Ltd | Professional & scientific | 2025 |
| D Monkhouse & Company Limited | Professional & scientific | 2012 |
| D P Scruton Limited | Professional & scientific | 2008 |
| D S Interior Solutions Limited | Construction | 2014 |
| D S Services (Salisbury) Limited | Construction | 2008 |
| D Yeatman Glaziers Limited | Construction | 2013 |
| D&D Publicans Limited | Hospitality | 2025 |
| D&N Construction Limited | Administrative & support | 2013 |
| D&N Salisbury Ltd | Financial services | 2022 |
| D&Sm Ltd | Administrative & support | 2018 |
| D&Y Transport Ltd | Transport & logistics | 2018 |
| D-Trak Limited | Information & communication | 1996 |
| D-Urban Project Management Limited | Administrative & support | 2012 |
| D. W. B. Long (Properties) Limited | Real estate | 2007 |
| D.A.Waite.Holdings Ltd | Real estate | 2025 |
| D.E.Staffing Limited | Administrative & support | 2018 |
| D.M.B. Carpenters Limited | Construction | 2003 |
| D.O.T. Specialists Ltd | Administrative & support | 2024 |
| D.W.B.Long Limited | Wholesale & retail | 1967 |
| D2L Logix Ltd | Professional & scientific | 2023 |
| D3A Defence Ltd | Professional & scientific | 2018 |
| DA Spago Limited | Wholesale & retail | 2009 |
| Daccs Services Limited | Construction | 2009 |
| Dadson and Butler Limited | Professional & scientific | 2006 |
| Daffurn & Co Ltd | Professional & scientific | 2007 |
| Dafoneleo Limited | Health & social care | 2014 |
| Dahima Smith Care Ltd | Administrative & support | 2023 |
| Daisies Oxford Flowers Ltd | Wholesale & retail | 2020 |
| Daisy Farming Company Limited | Agriculture & fishing | 1995 |
| Daisym Consulting Ltd | Information & communication | 2018 |
| Daiza Designs Ltd | Wholesale & retail | 2023 |
| DAK (Southern) Limited | Administrative & support | 2017 |
| Dalebeam Limited | Real estate | 1992 |
| Dalemount Limited | Professional & scientific | 2006 |
| Dalen (Holdings) Limited | Construction | 2013 |
| Dalen Cooker Services Limited | Other services | 2012 |
| Dalen Offshore Services Ltd | Administrative & support | 2023 |
| Daliz and SON Ltd | Wholesale & retail | 2023 |
| Damen Associates Limited | Professional & scientific | 2002 |
| Damm Group Ltd | Construction | 2021 |
| DAN Walters Motor Mechanics Limited | Wholesale & retail | 2015 |
| DAN Y Bryn Gaer Management Company (Number 2) Limited | Households | 2016 |
| DAN Y Bryn Gaer Management Company Limited | Households | 2014 |
| Danalight Lighting Limited | Wholesale & retail | 2019 |
| Dandelion Network Limited | Administrative & support | 2024 |
| Dandenong Freight Management Limited | Transport & logistics | 2024 |
| Dando Healthcare Services Ltd | Health & social care | 2023 |
| Danebury Land and Development Ltd | Real estate | 2024 |
| Danesdale Land Limited | Construction | 1989 |
| Danesdale Realisations Limited | Real estate | 2026 |
| Danhar Limited | Wholesale & retail | 2020 |
| Daniel Almond Limited | Professional & scientific | 2022 |
| Daniel Building Solutions Ltd | Construction | 2012 |
| Daniel J Hillier Limited | Construction | 2013 |
| Daniela Transport Ltd | Transport & logistics | 2022 |
| Daniels Tree & Garden Services Ltd | Administrative & support | 2026 |
| Dans Work Ltd | Information & communication | 2015 |
| Danst Solutions Ltd | Information & communication | 2014 |
| Darenth Management Limited | Households | 2015 |
| Dark Horse Ltd | Wholesale & retail | 1999 |
| Dark Revolution Ltd | Manufacturing | 2015 |
| Darren Macdonald Funeral Directors Limited | Other services | 2014 |
| Darren Moore Limited | Information & communication | 2010 |
| Darren Morgan Limited | Construction | 2011 |
| Darren Toms Coaching Ltd | Administrative & support | 2011 |
| Dart Finder Limited | Information & communication | 2026 |
| Dartmoor Farming Ltd | Agriculture & fishing | 2025 |
| Darwen Children's Services Limited | Financial services | 2016 |
| Dash Dogs | Health & social care | 2019 |
| Dasha Dasha Ltd | Transport & logistics | 2024 |
| Data Magik Limited | Professional & scientific | 1999 |
| Datakapture Limited | Information & communication | 2012 |
| Datasprints Strategy Advisory Ltd | Information & communication | 2026 |
| Dauwalder's Property & Investments LLP | | 2009 |
| Dauwalders' Ltd | Wholesale & retail | 2014 |
| Davally Book Keeping Services Limited | Professional & scientific | 2014 |
| Dave Dunford Limited | Financial services | 2018 |
| Daver Court Limited | Households | 2003 |
| Davey Construction Limited | Construction | 2006 |
| Daviart Holdings Limited | Financial services | 2017 |
| David G Johnson Limited | Information & communication | 2019 |
| David J Cutler Ltd | Professional & scientific | 2017 |
| David King (Farms) Limited | Professional & scientific | 1984 |
| David Pring Bricklaying Ltd | Construction | 2016 |
| Davies Agriculture Limited | Agriculture & fishing | 2013 |
| Davis Developments Ltd | Construction | 2019 |
| Davis Developments South Limited | Construction | 2018 |
| Davis Fencing Limited | Administrative & support | 2019 |
| Davis Plumbing Limited | Construction | 2010 |
| Davy Hospitality Ltd | Hospitality | 2022 |
| Dawlish View Management Company Limited | Households | 2024 |
| Dayex Investments Ltd | Professional & scientific | 2013 |
| Dayex Ltd | Wholesale & retail | 2013 |