| Cyboro Consulting Ltd | Information & communication | 2016 |
| Cyma Property Limited | Real estate | 2022 |
| Cyrus GAS & Mechanical Services Ltd | Construction | 2018 |
| D & C Matthews Consultancy Ltd | Information & communication | 2019 |
| D & P Electrical Services Ltd | Construction | 2005 |
| D & Sons Retails Ltd | Wholesale & retail | 2023 |
| D C LI (Builders) Limited | Construction | 1987 |
| D G Rally Limited | Wholesale & retail | 2016 |
| D W a Group Limited | Wholesale & retail | 2015 |
| D W a Print Limited | Manufacturing | 2017 |
| D&B Patterson Ltd | Professional & scientific | 2018 |
| D&E Bespoke Limited | Construction | 2018 |
| D. Templeton Building Services Limited | Construction | 2008 |
| DA Vinci Aviation Limited | Transport & logistics | 2015 |
| Dabawala & Read Limited | Professional & scientific | 2021 |
| DAC Cooling Ltd | Construction | 2022 |
| Daedal Ltd | Wholesale & retail | 2024 |
| Daedalus Auto Limited | Wholesale & retail | 2025 |
| Dafog Limited | Information & communication | 2023 |
| Daft Dog Ltd | Hospitality | 2025 |
| Dale Prince Investments Limited | Professional & scientific | 2019 |
| Dales Private Hire Limited | Transport & logistics | 2012 |
| Damgaard Services Limited | Professional & scientific | 2023 |
| DAN LPG Ltd | Transport & logistics | 2013 |
| DAN Trans Ltd | Transport & logistics | 2014 |
| Danbuild Construction Limited | Construction | 2021 |
| Dance That Stage Ltd | Arts & recreation | 2025 |
| Dane Adams Flooring Limited | Administrative & support | 2017 |
| Danebury Development Management Limited | Households | 2023 |
| Daniel Pitts Media Ltd | Information & communication | 2026 |
| Daniels Bathrooms Limited | Construction | 2023 |
| Danish Apple Photography Limited | Extraterritorial | 2015 |
| Danny Waite Consulting Ltd | Professional & scientific | 2023 |
| Danpl Ltd | Transport & logistics | 2023 |
| Dans Designer Ltd | Wholesale & retail | 2024 |
| Dapper Building Services Ltd | Construction | 2022 |
| Darpro Care Services Ltd | Health & social care | 2024 |
| Darpro Media Ltd | Professional & scientific | 2024 |
| Data Collect and Shred Ltd | Water & waste | 2022 |
| Databotics Ltd | Information & communication | 2025 |
| Davidson Consulting Ltd | Information & communication | 2013 |
| Dawes Highway Safety Limited | Manufacturing | 2015 |
| Dayview Food Ltd | Wholesale & retail | 2026 |
| DB Method Limited | Arts & recreation | 2022 |
| Dbmlinks Ltd | Administrative & support | 2016 |
| DBW Investment Properties Limited | Construction | 2022 |
| DC Automotive Diagnostics Ltd | Wholesale & retail | 2026 |
| DC Property Lets Ltd | Real estate | 2019 |
| DC PVT Ltd | Administrative & support | 2015 |
| Ddiy Solutions Limited | Construction | 2022 |
| DE Burgh Wilmot & Company Ltd | Professional & scientific | 2025 |
| Deal Shaper Ltd | Professional & scientific | 2016 |
| Decks by M.E Ltd | Wholesale & retail | 2025 |
| Defay Limited | Health & social care | 2014 |
| Deliverable FX Partners LLP | | 2019 |
| Delly’S Diggers Ltd | Administrative & support | 2026 |
| Delta 7 Ltd | Administrative & support | 2025 |
| Delta Safety Engineering Limited | Professional & scientific | 2026 |
| Deltic Solutions Limited | Construction | 2016 |
| Deluxe Padle Club Ltd | Arts & recreation | 2025 |
| Delve Into Renovation Ltd | Construction | 2025 |
| Denancial Ltd | Wholesale & retail | 2012 |
| Denplan Limited | Health & social care | 1986 |
| Denttrack PVT Ltd | Information & communication | 2022 |
| DEO Management Consultancy Ltd | Professional & scientific | 2017 |
| Derrydown Link Ltd | Construction | 2025 |
| Designautogroup Ltd | Wholesale & retail | 2018 |
| Dessert Kitchen Ltd | Hospitality | 2022 |
| Deublin Limited | Manufacturing | 1972 |
| Devlin Cues Limited | Administrative & support | 2012 |
| Dewbz Ltd | Wholesale & retail | 2022 |
| DF Mobility Limited | Wholesale & retail | 2016 |
| DFP Surveying Limited | Professional & scientific | 2023 |
| DG Auto Services Ltd Ltd | Wholesale & retail | 2024 |
| DGR Training Limited | Transport & logistics | 2015 |
| Diamond Assets Limited | Manufacturing | 2022 |
| Diamond Beauty Services Limited | Other services | 2025 |
| Diamond Defence Ltd | Information & communication | 2023 |
| Diamond Lush Events Limited | Other services | 2019 |
| Dicker Property Ltd | Hospitality | 2025 |
| Diddi Malek and Associates Limited | Arts & recreation | 1999 |
| Differential Consulting Ltd | Information & communication | 2009 |
| Digby Croft Limited | Households | 1983 |
| Digging IT Groundworks Ltd | Construction | 2006 |
| Digi Retention Ltd | Hospitality | 2017 |
| Digicad LAB PVT Ltd | Health & social care | 2026 |
| Digital Taskforce Hub Ltd | Wholesale & retail | 2024 |
| Dikku Property Limited | Real estate | 2024 |
| Dilworth & Smith Property Ltd | Real estate | 2024 |
| Dimensions Carpentry & Construction Limited | Construction | 2020 |
| Dimp Service Ltd | Manufacturing | 2019 |
| Direct Transport and Removals Ltd | Transport & logistics | 2020 |
| Divided by Mittens CIC | Arts & recreation | 2026 |
| Divine Glory Beauty and Spa Limited | Wholesale & retail | 2021 |
| DJ Parcels Limited | Transport & logistics | 2023 |
| DJB Support Limited | Administrative & support | 2016 |
| DJH Trading Ltd | Construction | 2017 |
| DJP Engineering Limited | Professional & scientific | 2024 |
| Djsj Floral Limited | Wholesale & retail | 2026 |
| Djsj Limited | Financial services | 2024 |