| Deaf Experience Limited | Professional & scientific | 2005 |
| Deal Assured Limited | Extraterritorial | 2005 |
| Deal Development Company Limited | Wholesale & retail | 2017 |
| Deal Development Security Ltd | Wholesale & retail | 2016 |
| Deal Drip Commerce Ltd | Wholesale & retail | 2026 |
| Deal Driven Motors Ltd | Wholesale & retail | 2026 |
| Deal House Limited | Wholesale & retail | 2018 |
| Deal Sourcing Network Limited | Information & communication | 2025 |
| DEAL4DOORS Ltd | Wholesale & retail | 2018 |
| Dealer Auction Limited | Administrative & support | 2018 |
| Dealer's Choice Ltd | Wholesale & retail | 2026 |
| Dealerstack Ltd | Wholesale & retail | 2026 |
| Dealhuntersuk Ltd | Administrative & support | 2026 |
| Dealings Limited | Professional & scientific | 1962 |
| Dealparks Limited | Information & communication | 2006 |
| Dean & Co. Cleaning Services Ltd | Administrative & support | 2023 |
| Dean Draper Ltd | Professional & scientific | 2023 |
| Dean Interiors (Leeds) Limited | Construction | 2013 |
| Dean P Durno Limited | Hospitality | 2025 |
| Dean Patterson Consultancy Ltd | Professional & scientific | 2023 |
| Dean Sykes Holdings Limited | Financial services | 2017 |
| Deane Consultancy Services Ltd | Professional & scientific | 2023 |
| Deanhill Consulting Ltd | Information & communication | 2020 |
| Deans Plumbing and GAS Ltd | Construction | 2025 |
| Deans Transport and Removals Ltd | Transport & logistics | 2025 |
| Dearlove Skin Limited | Other services | 2025 |
| Dearnley Digital Ltd | Information & communication | 2022 |
| Deat Consulting Limited | Professional & scientific | 2014 |
| Debar Ltd | Manufacturing | 2008 |
| Deberris Nurseries Limited | Administrative & support | 2002 |
| Debest Digital World Ltd | Wholesale & retail | 2026 |
| Debitscredits.Co.Uk Limited | Professional & scientific | 2020 |
| Debonair Motor Company Ltd | Wholesale & retail | 2025 |
| Debora Plumbing and Heating Ltd | Construction | 2025 |
| Deborah Ogden Limited | Professional & scientific | 2011 |
| Debra Homes Limited | Construction | 2016 |
| Debrun Limited | Construction | 2026 |
| Debsman Ltd | Health & social care | 2013 |
| Debt and Asset Recovery Limited | Financial services | 2015 |
| Debt Flow Automation Ltd | Information & communication | 2025 |
| Debt Management Services Ltd | Professional & scientific | 2025 |
| Debt Recovery Limited | Other services | 2017 |
| Debt Remedy Limited | Extraterritorial | 2011 |
| Debtenforcementairecoveries Ltd | Professional & scientific | 2026 |
| DEC Roofing (Yorkshire) Limited | Construction | 2026 |
| DEC Search Limited | Administrative & support | 2014 |
| Deca Consulting Limited | Professional & scientific | 2006 |
| Deca Properties Ltd | Real estate | 2011 |
| Decaid Global Trading Ltd | Wholesale & retail | 2026 |
| Decaid Ltd | Professional & scientific | 2021 |
| Decarbonisation Consulting Ltd | Professional & scientific | 2023 |
| Decarbonised Ltd | Professional & scientific | 2021 |
| Decarolis Distribution Ltd | Wholesale & retail | 2025 |
| Decent Overseas Limited | Administrative & support | 2025 |
| Decentlink Limited | Real estate | 2000 |
| Decision First Limited | Administrative & support | 2012 |
| Decisionone Consulting Limited | Information & communication | 1999 |
| Deckible Group Limited | Information & communication | 2023 |
| Decking Panels Ltd | Other services | 2024 |
| Decksaver Limited | Professional & scientific | 2012 |
| Declan James Consultancy Ltd | Professional & scientific | 2026 |
| Deco-Pak (Holdings) Limited | Financial services | 2024 |
| Deco-Pak Limited | Wholesale & retail | 2004 |
| Decodifi Limited | Information & communication | 2022 |
| Decor Elevate Ltd | Manufacturing | 2023 |
| Decoral York Ltd. | Other services | 2019 |
| Decorean Projects Limited | Construction | 2016 |
| Decorum 60 Ltd | Administrative & support | 2021 |
| Decostayle UK Limited | Professional & scientific | 2021 |
| Decouple Limited | Professional & scientific | 2011 |
| Dedalus UK Bidco Limited | Financial services | 2020 |
| Dedon Enterprises Ltd | Financial services | 2025 |
| DEE Cowburn Communications Limited | Professional & scientific | 2024 |
| DEE Savage Ltd | Professional & scientific | 2020 |
| Deeabal Limited | Transport & logistics | 2025 |
| Deegifind Limited | Information & communication | 2023 |
| Deej IO Ltd | Information & communication | 2025 |
| Deemar Haulage Ltd | Transport & logistics | 2025 |
| Deeno Technology Limited | Wholesale & retail | 2017 |
| Deenzo Services Ltd | Professional & scientific | 2021 |
| Deep Dive Data Ltd | Information & communication | 2023 |
| Deep Fresh Drinks Limited | Wholesale & retail | 2019 |
| Deep Healthcare Services Limited | Information & communication | 2023 |
| Deep Vertex Limited | Information & communication | 2026 |
| Deepblue Digital (Leeds) Limited | Information & communication | 2003 |
| Deepdale Systems Limited | Information & communication | 1993 |
| Deepdive Aquatics Ltd | Information & communication | 2026 |
| Deeppaya Digital Services Limited | Information & communication | 2022 |
| Deepstate Limited | Professional & scientific | 1981 |
| Deer Valley Properties Limited | Real estate | 2024 |
| Dees Busy Bees Ltd | Other services | 2017 |
| Dees Motors Ltd | Wholesale & retail | 2020 |
| Deetek Solutions Ltd | Professional & scientific | 2024 |
| Deevi Technologies Ltd | Information & communication | 2011 |
| Deewar Properties Ltd | Real estate | 2019 |
| Defi TM Limited | Financial services | 2020 |
| Defib Machines Limited | Administrative & support | 2011 |
| Define YOU - Skin Ltd | Other services | 2025 |
| Define YOU Ltd | Health & social care | 2021 |
| Defined by Gemma Limited | Other services | 2026 |