| Diamond Smile Ltd | Health & social care | 2015 |
| Dibben and Co Ltd | Administrative & support | 2021 |
| Didcot Laundrette Limited | Other services | 2024 |
| Diddly DO Ltd | Wholesale & retail | 2022 |
| Difford Kennels Limited | Other services | 2026 |
| Digby Services Limited | Real estate | 1999 |
| Digga Limited | Manufacturing | 2005 |
| Digital Edge Tech Limited | Wholesale & retail | 2024 |
| Digital Satellite and Cable Ltd | Administrative & support | 2009 |
| Digital Systems & Design Limited | Information & communication | 2004 |
| Digital Wonder Emporium Ltd | Professional & scientific | 2021 |
| Diligent Food Ltd | Hospitality | 2019 |
| Dillinghall Ltd | Manufacturing | 2011 |
| Diluvium Ltd | Real estate | 2012 |
| Dinazad Limited | Extraterritorial | 2002 |
| Dinton & Baverstock Manor Farms Limited | Agriculture & fishing | 1957 |
| Diplocks Way Limited | Extraterritorial | 2006 |
| Dippenhall Limited | Extraterritorial | 2013 |
| Dira Homes Limited | Real estate | 2024 |
| Ditlou Limited | Health & social care | 2018 |
| Diurnata Consulting Ltd | Professional & scientific | 2023 |
| Diversant Capital Limited | Administrative & support | 2015 |
| Divya Patel Legal Services Limited | Professional & scientific | 2019 |
| DJR Medico-Legal Services Limited | Health & social care | 2015 |
| Djra Homes Ltd | Real estate | 2019 |
| DK Financial Services Ltd | Financial services | 2020 |
| DML Land Profits Ltd | Real estate | 2026 |
| DMW Heating Limited | Construction | 2013 |
| DNA Developments (South) Limited | Construction | 2020 |
| Dnfr Aslan Limited | Construction | 2025 |
| Doblet Limited | Transport & logistics | 2024 |
| DOC in a Box Ltd | Health & social care | 2020 |
| Dock Gate Limited | Administrative & support | 2004 |
| Doctor Fade Limited | Other services | 2024 |
| Doddlecare Limited | Wholesale & retail | 2021 |
| Doddlecreation Limited | Wholesale & retail | 2014 |
| Dodzilla Limited | Hospitality | 2006 |
| Dohop UK Limited | Information & communication | 2018 |
| Doing IT Digital Limited | Information & communication | 2020 |
| Domestic Logbook Ltd | Information & communication | 2025 |
| Domo Renova Ltd | Construction | 2023 |
| Done That Ltd | Arts & recreation | 2021 |
| Donedry Ltd | Transport & logistics | 2025 |
| Doni Parcel Ltd | Transport & logistics | 2025 |
| Donnington and Woodlands (Winchester) Limited | Households | 1972 |
| Doorgear Ltd. | Construction | 2002 |
| Dorchester Court (Southampton) Limited | Households | 1996 |
| Douglas FIR Carpentry & Joinery Ltd | Construction | 2025 |
| Dovey Equestrian Limited | Education | 2025 |
| Down to Earth Winchester Limited | Administrative & support | 2021 |
| Downer & Co Ltd | Real estate | 1992 |
| Downhouse Consulting Limited | Professional & scientific | 2013 |
| Downland Fieldsports Limited | Arts & recreation | 2014 |
| Downlands Equestrian Limited | Agriculture & fishing | 2003 |
| Downlands Sporting Limited | Arts & recreation | 2012 |
| Downley Consultants Limited | Professional & scientific | 2015 |
| Doyuk Ltd | Wholesale & retail | 2025 |
| DR a J Sansome Ltd | Professional & scientific | 2013 |
| DR M Kerton Anaesthesia Limited | Health & social care | 2021 |
| DR Sarah Aesthetics Ltd | Health & social care | 2023 |
| DR SJ Training Ltd | Education | 2024 |
| DR Thomson's Tours Ltd | Administrative & support | 2013 |
| DR V J Pappachan Limited | Health & social care | 2010 |
| DR. Julian Nixon Limited | Health & social care | 2010 |
| DR. Stephen Wimbush Limited | Health & social care | 2011 |
| Dragon Land Profits Limited | Real estate | 2024 |
| Dragonfly London Residential Ltd | Professional & scientific | 2023 |
| Drawnalism Ltd | Administrative & support | 2013 |
| Drcmeducation Ltd | Education | 2025 |
| Drconsult Limited | Professional & scientific | 2017 |
| DRE Digital Limited | Information & communication | 2012 |
| Dream Cars Winchester Ltd | Transport & logistics | 2014 |
| Dream Engine Limited | Information & communication | 2020 |
| Dreamy IT Services Ltd | Information & communication | 2024 |
| Driven NOT Hidden UK Ltd | Professional & scientific | 2024 |
| DRM Forestry Ltd | Agriculture & fishing | 2024 |
| Drop the Bottle Ltd | Arts & recreation | 2015 |
| Drove Mews MC Limited | Households | 2009 |
| Drum Domus Ltd | Real estate | 2025 |
| Drumco Events Ltd. | Other services | 1994 |
| Drummer Properties Ltd | Real estate | 2024 |
| DRY Dolly Ltd | Wholesale & retail | 2023 |
| DS Event Consulting Limited | Professional & scientific | 2025 |
| DSC Global Ltd | Professional & scientific | 2024 |
| DSH Builders Limited | Construction | 2016 |
| DSM Structural Ltd | Construction | 2024 |
| Dsnm Limited | Information & communication | 2007 |
| Dstrct Productions Limited | Professional & scientific | 2024 |
| DT Coffee Ltd | Other services | 2022 |
| DT Fitness Winchester Ltd | Arts & recreation | 2023 |
| Dukes Limited | Real estate | 1957 |
| Dulcet Media Limited | Information & communication | 2021 |
| Dumper's Carpentry & Construction Ltd | Construction | 2024 |
| Dunarden Limited | Financial services | 1953 |
| Duncan Hamilton Rofgo Limited | Wholesale & retail | 2017 |
| Duncan PIC Limited | Financial services | 2020 |
| Dunmarsurveyors Ltd | Professional & scientific | 2024 |
| Duntroon Consultants Limited | Professional & scientific | 2014 |
| Dunwin Properties Limited | Households | 1972 |
| Durris Properties Limited | Real estate | 2013 |