| Doull Property Ltd | Real estate | 2021 |
| Dousti Ltd | Wholesale & retail | 2024 |
| Dove Recruiters Ltd | Other services | 2019 |
| Doventix Ltd | Wholesale & retail | 2025 |
| Dovetail Communications Limited | Arts & recreation | 2008 |
| Dovetail Partners Ltd | Information & communication | 2019 |
| Dovey Enterprises Limited | Real estate | 2021 |
| Dovey Holdings South Wales Limited | Real estate | 1996 |
| Dowd Kennedy Contracting Ltd | Transport & logistics | 2016 |
| Dowlais Curry House Ltd | Hospitality | 2025 |
| Dowlais Top Investment Company Limited | Real estate | 1963 |
| Down to Earth Property Maintenance Ltd | Construction | 2025 |
| Downlands Way Residents Ltd | Administrative & support | 2020 |
| Download DBA Ltd | Information & communication | 2019 |
| Download Ltd | Wholesale & retail | 2021 |
| Downs Construction Limited | Construction | 1988 |
| Downs Merrifield Limited | Professional & scientific | 2014 |
| Downunder Cafe Limited | Hospitality | 2002 |
| Dowra Wholesalers Limited | Professional & scientific | 2025 |
| Dowsen Ltd | Wholesale & retail | 2023 |
| Doyle Davies Consultancy Limited | Other services | 1992 |
| Doyle Davies Insolvency Limited | Other services | 1999 |
| Doyle Davies Limited | Financial services | 1997 |
| Doyle Insolvency Limited | Other services | 2014 |
| Doyle Recovery Limited | Other services | 2015 |
| Doyle Rescue Limited | Other services | 2015 |
| Doyle Restructure Limited | Other services | 2015 |
| Dozget Private Limited | Construction | 2025 |
| Dozhi Limited | Wholesale & retail | 2021 |
| DP Developments & Construction Ltd | Construction | 2020 |
| DP Digital Online Ltd | Information & communication | 2025 |
| DP Motors Ltd | Wholesale & retail | 2017 |
| DP Shayban Limited | Hospitality | 2012 |
| DP Teamwear Ltd | Manufacturing | 2019 |
| DP2 Consulting Ltd | Professional & scientific | 2019 |
| Dpbuk Ltd | Hospitality | 2025 |
| DPD Maintenance Ltd | Wholesale & retail | 2022 |
| DPG Decorators Limited | Construction | 2017 |
| DPG Roofing Limited | Construction | 2019 |
| DPH Dorset Ltd | Construction | 2017 |
| DPK Consultants Ltd | Professional & scientific | 2020 |
| DPK Group Ltd | Wholesale & retail | 2019 |
| Dpln Limited | Professional & scientific | 2006 |
| DPM Tile Solutions Ltd. | Construction | 2017 |
| DPP One Limited | Professional & scientific | 2012 |
| DPS Architecture Ltd. | Professional & scientific | 2013 |
| Dpsw Ltd | Real estate | 2022 |
| DPT Hips Limited | Health & social care | 2020 |
| DPT Property Ltd. | Real estate | 2018 |
| DPW Recycling Ltd | Water & waste | 2023 |
| DR a Jayakumar Limited | Health & social care | 2014 |
| DR Adrian Goldsworthy Limited | Arts & recreation | 2020 |
| DR Andrew Medicolegal Psychiatric Reports Ltd | Health & social care | 2024 |
| DR Bridget NLP Limited | Professional & scientific | 2017 |
| DR C R Aldridge Limited | Health & social care | 2009 |
| DR Chloe Harrington-Taylor Limited | Health & social care | 2023 |
| DR Cool Air Conditioning Ltd | Construction | 2023 |
| DR Cool Renewables Ltd | Construction | 2024 |
| DR Daniel Mock Limited | Health & social care | 2023 |
| DR Ellis Stiles Limited | Health & social care | 2022 |
| DR Emma Blake Ltd | Information & communication | 2016 |
| DR Etman Ltd | Health & social care | 2024 |
| DR Ghali Salahia Ltd | Professional & scientific | 2020 |
| DR Goyal Ltd | Health & social care | 2014 |
| DR Irfan a. Pitafi Ltd | Wholesale & retail | 2025 |
| DR ITA Lyons Ltd | Health & social care | 2025 |
| DR JJC Ltd | Health & social care | 2022 |
| DR KAT Limited | Health & social care | 2024 |
| DR Kate Rhodes Ltd | Health & social care | 2020 |
| DR Kathryn Aesthetics and Skincare Ltd | Other services | 2021 |
| DR Katina Kontos Ltd | Health & social care | 2023 |
| DR Kelly Lloyd Health Care Ltd | Health & social care | 2022 |
| DR Khalid ALI Ltd | Health & social care | 2019 |
| DR Lindsay David George Ltd | Health & social care | 2018 |
| DR M Aziz Limited | Health & social care | 2018 |
| DR M T Shafik Limited | Health & social care | 2011 |
| DR Martin Bevan Limited | Health & social care | 2014 |
| DR Maziyah Clinic Ltd | Administrative & support | 2025 |
| DR Megan Mccrea Limited | Health & social care | 2023 |
| DR MMU Chowdhury Limited | Health & social care | 2011 |
| DR Mohid S Khan Ltd | Education | 2019 |
| DR Nancy London PVT Ltd | Other services | 2020 |
| DR Nick Groves Ltd | Health & social care | 2014 |
| DR Patrick Butler Limited | Health & social care | 2014 |
| DR Paul Rogers Limited | Professional & scientific | 2017 |
| DR Peter O'Callaghan Limited | Health & social care | 2012 |
| DR Polish Builders Ltd | Construction | 2017 |
| DR Qaisar Limited | Administrative & support | 2020 |
| DR R a Davey Limited | Professional & scientific | 2007 |
| DR Renate Homewood Limited | Health & social care | 2013 |
| DR Rhys Redford Limited | Health & social care | 2023 |
| DR Sanitise Ltd | Administrative & support | 2020 |
| DR Sanjeet RAO Ltd | Health & social care | 2012 |
| DR Skin Cardiff Ltd | Health & social care | 2023 |
| DR Sura Yousif Ltd | Health & social care | 2019 |
| DR V Farooq Limited | Health & social care | 2024 |
| DR Valentim Aesthetics Limited | Health & social care | 2021 |
| DR Vian Aziz Ltd | Health & social care | 2026 |
| Dr-Surfing-Lobby Ltd | Wholesale & retail | 2025 |
| DR. Aldaas Ltd | Health & social care | 2025 |