| Delta Q Consulting Limited | Administrative & support | 2010 |
| Delta Y Electrical Ltd | Construction | 2016 |
| DELTA6 UAV Ltd | Professional & scientific | 2025 |
| Deltavon Developments Limited | Real estate | 2007 |
| Deltron Distribution Ltd | Wholesale & retail | 2023 |
| Delux Management Limited | Wholesale & retail | 2015 |
| Deluxe Builders Network Ltd | Construction | 2023 |
| Deluxe Business Services Ltd | Professional & scientific | 2024 |
| Deluxe Decorating Services Ltd | Construction | 2019 |
| Deluxe Decorating South West Ltd | Construction | 2026 |
| Delv Media Ltd | Administrative & support | 2015 |
| Demacan Limited | Real estate | 1979 |
| Demagilis UK Limited | Professional & scientific | 2015 |
| Demand Film (UK) Ltd | Information & communication | 2016 |
| Demand Marketing Consultancy Ltd | Information & communication | 2018 |
| Demandbase Limited | Professional & scientific | 2015 |
| Demareqs Ltd | Administrative & support | 2010 |
| Demari Boat Company Limited | Manufacturing | 2015 |
| Dembo Enterprise Ltd | Health & social care | 2021 |
| Demcat Investments Ltd | Real estate | 2026 |
| Demello Ltd | Information & communication | 2024 |
| Demelza Services Limited | Arts & recreation | 1984 |
| Demerara Property Holdings Ltd | Financial services | 2017 |
| Demerara Property Investments Ltd | Real estate | 2017 |
| Demi PR UK Ltd | Professional & scientific | 2023 |
| Democrata Data Services Limited | Information & communication | 2016 |
| Demolition MAN Limited | Construction | 2022 |
| Demon Llama Limited | Professional & scientific | 2013 |
| Demonpen Ltd | Information & communication | 2006 |
| DEN Dental Group Practice LLP | | 2008 |
| DEN Propco Limited | Real estate | 2024 |
| Denali Group Limited | Other services | 2019 |
| Denbrook Developments Ltd | Construction | 2018 |
| Dencraft (Leicester) Ltd | Manufacturing | 2009 |
| Dencraft (South Yorkshire) Limited | Manufacturing | 2011 |
| Dendarii Holdings Limited | Financial services | 2026 |
| Dendri Design Limited | Construction | 2017 |
| Deneplan Limited | Information & communication | 2024 |
| Deneto Properties Ltd | Real estate | 2017 |
| Denford Trade LP | | 2011 |
| Denhay Farms Limited | Manufacturing | 1952 |
| Deniable Productions Ltd | Information & communication | 2019 |
| Denlor IT Consultants Limited | Information & communication | 1998 |
| Denmaker Ltd | Extraterritorial | 2014 |
| Denman Trustees Limited | Agriculture & fishing | 2013 |
| Denney & Co. Ltd. | Financial services | 1991 |
| Denneys Ltd | Construction | 2019 |
| Dens Store Ltd | Wholesale & retail | 2025 |
| Densley Property Developments Ltd | Manufacturing | 2021 |
| Densley Property Ltd | Real estate | 2022 |
| Dental Capital Partners Limited | Professional & scientific | 2009 |
| Dental Smile Work Ltd | Health & social care | 2024 |
| Dental Wellness Holdings Limited | Health & social care | 2019 |
| Dentalign Colwyn Bay Ltd | Health & social care | 2008 |
| Dentalign Eastbourne Ltd | Health & social care | 2008 |
| Dentalign Orthodontics Limited | Financial services | 2007 |
| Dentalign Orthodontics LLP | | 2007 |
| Dentalign Wrexham Ltd | Health & social care | 2008 |
| Dentalpol Products and Supplies Limited | Health & social care | 2010 |
| Dentex Ltd | Manufacturing | 2016 |
| Dentfixx Limited | Wholesale & retail | 2024 |
| Denthype Ltd | Wholesale & retail | 2023 |
| Dentina Healthcare Limited | Health & social care | 2023 |
| Dentina Limited | Health & social care | 2006 |
| Dentmagic (South West) Limited | Wholesale & retail | 2002 |
| Dentpass Limited | Education | 2026 |
| Dents Only Ltd | Wholesale & retail | 2024 |
| Denys Cleaning Ltd | Administrative & support | 2026 |
| Deommah Limited | Health & social care | 2024 |
| Deova Ltd | Other services | 2019 |
| DEP Business Services Ltd | Professional & scientific | 2011 |
| Department Films Limited | Information & communication | 2014 |
| Dependable MAC Ltd | Professional & scientific | 2007 |
| Depictions Ltd | Manufacturing | 2017 |
| Depop Limited | Administrative & support | 2012 |
| Depth and Breadth IS Ltd | Information & communication | 2021 |
| Depth Consulting Ltd | Construction | 2019 |
| DER Alia Ltd | Financial services | 2025 |
| Derby Wild Sauna Ltd | Other services | 2026 |
| Derek Murray Formwork Ltd | Construction | 2018 |
| Derek Plummer Contracts Limited | Construction | 1980 |
| Derlani Ltd | Real estate | 2025 |
| Dermadec Ltd | Health & social care | 2024 |
| Dermavet Ltd | Professional & scientific | 2026 |
| Derrett Young Transhaul Ltd. | Transport & logistics | 2017 |
| Derrick Construction Southwest Ltd | Construction | 2025 |
| Derwen DEG Limited | Professional & scientific | 2010 |
| Derwent House Orthodontics Limited | Health & social care | 2008 |
| DES Kelly Media Limited | Information & communication | 2013 |
| DES Solutions Limited | Professional & scientific | 2005 |
| Descale and Chlorination Services Limited | Health & social care | 2001 |
| Descare Ltd | Health & social care | 2021 |
| Descrier Limited | Information & communication | 2012 |
| Deseret Ventures UK Ltd | Wholesale & retail | 2026 |
| Desi Dera Easton Ltd | Hospitality | 2022 |
| Desi Roots Collective CIC | Education | 2025 |
| Desi Roots Ltd | Wholesale & retail | 2026 |
| Desideratum Psychological and Counselling Services Limited | Health & social care | 2013 |
| Design & Crafted Interiors Ltd | Manufacturing | 2020 |
| Design & Development Services Limited | Construction | 2003 |