| Dream Build Homes NE Ltd | Construction | 2026 |
| Dream TAN Ltd | Other services | 2022 |
| Drinkeze Limited | Manufacturing | 2025 |
| Driver Aware Ltd | Education | 2009 |
| Driveways and Patios North East Ltd | Construction | 2022 |
| Ds&A Services Limited | Construction | 2024 |
| DTL & Family Ltd | Other services | 2023 |
| DTR Ltd | Construction | 2025 |
| DUE Renovations Ltd | Construction | 2024 |
| Duke Technology Limited | Information & communication | 2019 |
| Dumpas Remaps Ltd | Wholesale & retail | 2020 |
| Duncan Colquhoun Construction Services Limited | Construction | 2014 |
| Dunelm Advisors Ltd | Professional & scientific | 2013 |
| Dunelm Propco Ltd. | Real estate | 2008 |
| Dunster House Management Co. Limited | Real estate | 1999 |
| Durham Arena & Leisure Ltd | Construction | 2024 |
| Durham Arena Leisure Ltd | Construction | 2026 |
| Durham Automobile Club Limited | Arts & recreation | 1983 |
| Durham Consultancy Ltd | Professional & scientific | 2019 |
| Durham Discus Ltd | Wholesale & retail | 2013 |
| Durham Investment Group Limited | Real estate | 2020 |
| Durham Kitchens & Bathrooms Ltd | Manufacturing | 2016 |
| Durham Road Catering Ltd | Hospitality | 2023 |
| Durham Surgical Services Limited | Health & social care | 2012 |
| Durham Wildlife Services Limited | Professional & scientific | 1991 |
| Durham Wildlife Trust | Arts & recreation | 1971 |
| DW Building Solutions (Durham) Ltd | Construction | 2015 |
| DW Plant Services (NE) Limited | Other services | 2025 |
| EAE Lettings Ltd | Real estate | 2026 |
| Eagle Hydroponic Ltd | Wholesale & retail | 2025 |
| Earth and Rose Ltd | Other services | 2024 |
| Earthrise Global Innovations Limited | Professional & scientific | 2024 |
| Earthus Limited | Agriculture & fishing | 2024 |
| Easington Lane Community Access Point | Transport & logistics | 2001 |
| Easington Lane Food Hub Ltd | Hospitality | 2025 |
| Easy Heating & Plumbing Ltd | Construction | 2025 |
| Easy Power Limited | Extraterritorial | 2006 |
| ECW Financial Services Limited | Financial services | 2025 |
| EDF ER Development Limited | Energy | 2015 |
| Edge Stone PT Ltd | Households | 2026 |
| Ediska Limited | Education | 2015 |
| Edsp Solutions Limited | Construction | 2022 |
| Edzoocation Ltd | Education | 2022 |
| Efficient Utility Solutions Ltd | Construction | 2024 |
| EH Pipe Fitting Ltd | Construction | 2016 |
| EJA Trade Ltd | Wholesale & retail | 2023 |
| EJS Property Group Ltd | Real estate | 2025 |
| Ekoptom Ltd | Health & social care | 2023 |
| Elba Park Joinery & Installations Ltd | Construction | 2021 |
| Elbon Leisure Ltd | Hospitality | 2025 |
| Elegance Care and Support Ltd | Public administration | 2020 |
| Elemore Collective CIC | Hospitality | 2025 |
| Elevate Logistics NE Ltd | Transport & logistics | 2025 |
| Elite & Prestige Ltd | Professional & scientific | 2018 |
| ELL Engineering Limited | Manufacturing | 2026 |
| Elle Property Developments Limited | Real estate | 2017 |
| Ellesmere Leisure Ltd | Hospitality | 2020 |
| Elliot Adamson Music Limited | Arts & recreation | 2017 |
| Ellwoodkitchens Ltd | Manufacturing | 2012 |
| Elwick Moncur Ltd. | Real estate | 2017 |
| EMK Pharm Ltd | Health & social care | 2019 |
| Endgame Business Coaching Ltd | Extraterritorial | 2021 |
| Engage Resolutions Ltd | Administrative & support | 2023 |
| Enlightened Wellbeing Psychological Services Limited | Health & social care | 2024 |
| Episteme Aerospace Ltd | Manufacturing | 2013 |
| Epos Solutions Limited | Manufacturing | 2017 |
| Ertumop Cleaning Solutions Ltd | Administrative & support | 2019 |
| ES Electrical Ltd | Construction | 2021 |
| Esco Glazing & Construction Ltd | Construction | 2009 |
| Essa Property Management Ltd | Real estate | 2026 |
| Euro Duct Clean Limited | Administrative & support | 2016 |
| Evangelical Church the Whatchmen of GOD CIC | Other services | 2021 |
| Everbeyond Ltd | Information & communication | 2024 |
| Evergreen Project Services Ltd | Professional & scientific | 2006 |
| Evolution Fitness (Durham) Ltd | Arts & recreation | 2024 |
| Evolution Fitness (Houghton) Ltd | Arts & recreation | 2019 |
| Evolve Collectively Ltd | Health & social care | 2025 |
| Evolve Data Solutions Ltd | Information & communication | 2014 |
| Evolve Elearning Limited | Education | 2025 |
| Exceed Communications Limited | Information & communication | 2008 |
| F H T Developments Limited | Construction | 2018 |
| F K Solutions (UK) Limited | Manufacturing | 2003 |
| Fabio's to Go Ltd | Hospitality | 2024 |
| Fabtek Solutions Limited | Manufacturing | 2010 |
| Fare Taxis Limited | Transport & logistics | 2025 |
| FAT Loss Feast Ltd | Other services | 2021 |
| Fellside Mews RTM Company Limited | Real estate | 2014 |
| Fencehouses MOT Centre Ltd | Manufacturing | 2016 |
| Fencehouses Truss Company Limited | Manufacturing | 2006 |
| Fenmio Ltd | Wholesale & retail | 2026 |
| Fernley Group Ltd | Energy | 2018 |
| Ferry's Fencing and Landscaping Ltd | Construction | 2024 |
| Fest Events North East CIC | Professional & scientific | 2025 |
| Ffcaccess Ltd | Professional & scientific | 2024 |
| Field Cosmetics Ltd | Wholesale & retail | 2024 |
| Fieldhouse Photography and Curating CIC | Professional & scientific | 2019 |
| First Class Residential Ltd | Real estate | 2016 |
| First Rate Mortgages Ltd | Financial services | 2018 |
| Fitfaster Ltd | Wholesale & retail | 2024 |
| Fitzgerald Property Investments Limited | Real estate | 2018 |