| Darnfine Ltd | Hospitality | 2020 |
| Darren Pearce Property Maintenance Ltd | Construction | 2025 |
| Data Solutionz Limited | Information & communication | 2023 |
| Data Strategy Consulting Limited | Professional & scientific | 2013 |
| Dataive Limited | Information & communication | 2021 |
| Daughter Properties Ltd | Real estate | 2021 |
| Dave Wood Racing Ltd | Wholesale & retail | 2026 |
| David Thomas Motors Limited | Wholesale & retail | 2024 |
| David Tidmarsh Consulting Limited | Education | 2019 |
| David Whittles SAW Company Ltd | Wholesale & retail | 2011 |
| DB Motorsport Engineering Limited | Professional & scientific | 2024 |
| DD66 Limited | Real estate | 2022 |
| Deaf First CIC | Health & social care | 2026 |
| Deaf Horizons CIC | Health & social care | 2026 |
| Dean ST Creative Holdings Ltd | Financial services | 2024 |
| Deane Engineering Ltd | Professional & scientific | 2019 |
| Deane Performance Ltd | Wholesale & retail | 2019 |
| Deermark Farm Ltd | Professional & scientific | 2024 |
| Degrees With Dyslexia Ltd | Education | 2021 |
| Deltec Investments Limited | Financial services | 2010 |
| Denis Pizza Ltd | Hospitality | 2022 |
| Denstore Limited | Real estate | 1982 |
| Dermal Studio Ltd | Health & social care | 2021 |
| Design by Matilda Ltd | Professional & scientific | 2023 |
| Design Punks Limited | Extraterritorial | 2013 |
| Designer Flowers by Rodgers Limited | Wholesale & retail | 2008 |
| Dethink Ltd | Information & communication | 2025 |
| Develop Coaching Services Limited | Professional & scientific | 2010 |
| Devgifts Limited | Wholesale & retail | 2019 |
| Didcot Events CIC | Other services | 2017 |
| Diffatech Ltd | Information & communication | 2012 |
| Different Steps CIC | Education | 2025 |
| Digital Portunus Ltd | Information & communication | 2013 |
| Dinvas Limited | Health & social care | 2023 |
| Dinvas Properties Limited | Real estate | 2026 |
| Direct Drive Logistics Ltd | Transport & logistics | 2022 |
| Displays Direct Ltd | Wholesale & retail | 2010 |
| DJB Developments Limited | Construction | 2016 |
| DJG Security Consulting Ltd | Administrative & support | 2017 |
| DJL Fire Safety Consultancy Limited | Public administration | 2022 |
| DJY Ltd | Health & social care | 2024 |
| DK Financing Limited | Financial services | 2023 |
| DMA Motorsport Services Ltd | Wholesale & retail | 2025 |
| Dmirac Ltd | Hospitality | 2025 |
| DMR Contractors Ltd | Construction | 2019 |
| DNM Curated Consultancy Ltd | Administrative & support | 2024 |
| Dotd UK Limited | Professional & scientific | 2023 |
| Dotted Lines Consultancy Ltd | Information & communication | 2024 |
| DP Electrical Equestrian Limited | Professional & scientific | 2007 |
| DPG Group Holdings Ltd | Financial services | 2026 |
| DPG Labs Ltd | Information & communication | 2026 |
| DR F Nizami Practice Ltd | Health & social care | 2020 |
| Dragon B Ltd | Wholesale & retail | 2009 |
| Dragonfly@Home Limited | Professional & scientific | 2009 |
| Drainwise Services (UK) Ltd | Administrative & support | 2019 |
| Drakewell Corporate Investments Limited | Other services | 2022 |
| Drakewell Limited | Information & communication | 2011 |
| Drayton Asset Management Limited | Real estate | 2024 |
| DSL Solutions (UK) LLP | | 2012 |
| DTS Periti Limited | Professional & scientific | 2019 |
| Dunn's Windows and Gutters Ltd | Administrative & support | 2025 |
| Dunscannin Limited | Real estate | 2025 |
| Durbanite Residential Ltd | Real estate | 2023 |
| Durbin Security Solutions Ltd | Administrative & support | 2024 |
| Durotan Contracts Limited | Construction | 1993 |
| Durotan Holdings Limited | Financial services | 2017 |
| Durotan Limited | Construction | 1968 |
| Durotan Management Services Limited | Construction | 2017 |
| Durotan Products Ltd | Construction | 1978 |
| Dvntechnologies Limited | Information & communication | 2025 |
| DXA Electrical Services Ltd | Construction | 2026 |
| Dymond Motorsport Limited | Professional & scientific | 2022 |
| Dynax Services Limited | Information & communication | 2014 |
| E - Mechanic Ltd | Manufacturing | 2025 |
| E-Tradeway Limited | Wholesale & retail | 2005 |
| E-Truss Ltd | Construction | 2022 |
| Earlydrop Logistics Ltd | Transport & logistics | 2025 |
| Easily Home Limited | Real estate | 2020 |
| Eastman Engineering Consultants Limited | Professional & scientific | 2013 |
| Eaton Travis Consulting Ltd | Wholesale & retail | 2015 |
| EAU Rouge Limited | Professional & scientific | 2003 |
| EC Autosport Ltd | Professional & scientific | 2024 |
| Ecclesautocare Ltd | Wholesale & retail | 2024 |
| ECH Consultancy Ltd | Professional & scientific | 2022 |
| Echoedge AI Ltd | Information & communication | 2025 |
| ECM Retail Consulting Ltd | Professional & scientific | 2018 |
| Ecooltec UK Ltd | Transport & logistics | 2022 |
| Ecorporate Learning Ltd | Education | 2020 |
| Ecorporate Web Services Ltd | Wholesale & retail | 2012 |
| Ecovation Limited | Professional & scientific | 2017 |
| Ecovery Innovations Limited | Manufacturing | 2008 |
| Edgar Taylor Homes Limited | Construction | 2018 |
| Edgar Taylor Limited | Professional & scientific | 2004 |
| Educare Renewables Ltd | Construction | 2025 |
| Educational Psychology Pathways Ltd | Education | 2025 |
| Effective Electrics Ltd | Construction | 2025 |
| Efficiency Concepts Limited | | 1986 |
| Eggy PC Services Limited | Manufacturing | 2022 |
| Ehtsham Abbas Limited | Wholesale & retail | 2026 |
| Electricity Network Contractors (East) Limited | Energy | 2018 |