| Delta Wiring Solutions Ltd | Construction | 2019 |
| Demeter North East Limited | Real estate | 2023 |
| Denhill House Management Limited | Households | 2003 |
| Dentwip Limited | Professional & scientific | 2013 |
| Design by Melissa Ltd | Professional & scientific | 2022 |
| Design Five Five Ltd | Information & communication | 2024 |
| Dessert Hub North East Ltd | Other services | 2022 |
| Destinations by John Ltd | Administrative & support | 2021 |
| Device Care Ltd | Wholesale & retail | 2017 |
| DFP Communications Ltd | Construction | 2026 |
| DG Consulting Services Ltd | Professional & scientific | 2026 |
| DG Plumbing and Pipefitting Services Ltd | Manufacturing | 2015 |
| DHN Property Services Ltd | Real estate | 2002 |
| DHP Anaesthesia Ltd | Health & social care | 2023 |
| DI Meo's Riverside Limited | Hospitality | 2019 |
| DI Meo’S Tynemouth Limited | Hospitality | 2021 |
| Digital Templating Solutions Ltd | Information & communication | 2022 |
| Dimitris Pizza Limited | Hospitality | 2003 |
| Direct Choice Mortgages Limited | Financial services | 2025 |
| Dishmanbaird LLP | | 2025 |
| Divine Dining @ the Red Lion Limited | Hospitality | 2020 |
| DIY Designs and Innovations (UK) Ltd | Manufacturing | 2020 |
| Djic Consulting Ltd | Professional & scientific | 2026 |
| DJK Architect Ltd | Professional & scientific | 2013 |
| DJL Landscaping and Grounds Maintenance Ltd | Other services | 2003 |
| Dkmc Ltd | Professional & scientific | 2024 |
| DLM Property Solutions Ltd | Real estate | 2020 |
| DMAHOLDINGS74 Ltd | Real estate | 2024 |
| Dobbie Investments Limited | Real estate | 2024 |
| Dockwray Property Ltd | Real estate | 2022 |
| Doctor Bird Ltd | Wholesale & retail | 2019 |
| Doddle Soft Ltd | Information & communication | 2017 |
| Dodds Avenue Investments Ltd | Real estate | 2025 |
| Dolly Dot's Ltd | Wholesale & retail | 2024 |
| Domain Property & GAS Services Limited | Construction | 2013 |
| Dongard Holdings 2 Limited | Financial services | 2020 |
| Dongard M&E Holdings Limited | Financial services | 2019 |
| Dongard Properties Limited | Real estate | 2010 |
| Dongard Property Holdings 2 Limited | Financial services | 2020 |
| Dongard Property Holdings Limited | Financial services | 2019 |
| Dongard Scaffolding Limited | Construction | 2014 |
| Double ROW Pizza Ltd | Hospitality | 2018 |
| Dowco Contracting Ltd | Information & communication | 2022 |
| Dowco Ltd | Information & communication | 2020 |
| DP Auto Electrics Limited | Wholesale & retail | 2022 |
| DPJ Build Limited | Construction | 2012 |
| DR Adam Jakes Ltd | Education | 2017 |
| DR D. Jefferson G.P. Limited | Health & social care | 2015 |
| DR Vaughan Aesthetics Ltd | Health & social care | 2021 |
| Dracts Limited | Information & communication | 1998 |
| Dragonfly Cancer Trust Limited | Health & social care | 2016 |
| Dragonstone Films Ltd. | Information & communication | 2015 |
| Drakestone Holdings Limited | Real estate | 2021 |
| Dreamview Developments Ltd | Real estate | 2025 |
| Drew Michael Music Ltd | Arts & recreation | 2025 |
| DRH Properties North East Limited | Real estate | 2025 |
| Drone Associates Limited | Hospitality | 2012 |
| DS Advisors Limited | Professional & scientific | 2021 |
| DS Tree Management Ltd | Agriculture & fishing | 2025 |
| Dsmith Deliveries Ltd | Transport & logistics | 2026 |
| Dtlh Limited | Wholesale & retail | 2021 |
| Dulson Ventures Ltd | Real estate | 2024 |
| Dunes Financial Management Limited | Financial services | 2025 |
| Dunn NE25 Ltd | Real estate | 2020 |
| Durai Retail Ltd | Wholesale & retail | 2019 |
| Durham Ice and Sports Stadiums Limited | Arts & recreation | 1952 |
| DVS Components Ltd | Wholesale & retail | 2019 |
| Dwaa Properties Ltd | Real estate | 2025 |
| DWC and Sons Wind Ltd | Construction | 2026 |
| DWN Properties Ltd | Real estate | 2017 |
| Dytham Jewellery Designers Limited | Manufacturing | 2016 |
| E & K Foster Ltd | Real estate | 2024 |
| E B D Facilities Limited | Construction | 2012 |
| E Midgley & Co Limited | Financial services | 2015 |
| E Osikilo Limited | Financial services | 2016 |
| E.Y Civils Ltd | Construction | 2024 |
| EAL and Diversity Solutions Ltd | Education | 2023 |
| Earl & EVE Limited | Hospitality | 2024 |
| Easiflow Showers Limited | Construction | 2010 |
| East Coast Roofing and Building Ltd | Construction | 2017 |
| Eastbourne Gardens Store Limited | Wholesale & retail | 2019 |
| EAT Clean Limited | Hospitality | 2022 |
| EC Solutions NE Ltd | Professional & scientific | 2010 |
| Echj Properties Ltd | Real estate | 2024 |
| Eco Efficiency Energy Limited | Professional & scientific | 2013 |
| Eco Warmth Heating Solutions Ltd | Construction | 2022 |
| Ecomediamarketing Ltd | Information & communication | 2023 |
| Edac Estates Ltd | Real estate | 2026 |
| EDC Property Investments Ltd | Real estate | 2026 |
| Edelweiss Christmas Tree Company Limited | Wholesale & retail | 2008 |
| Eden Landscapes Love Your Garden Limited | Administrative & support | 2013 |
| Eden Tech Labs Ltd | Education | 2026 |
| Education for Employability Limited | Education | 2024 |
| Edwin House Management Company Limited | Households | 1980 |
| EJR Property Ltd | Real estate | 2019 |
| Eladnit Ltd | Professional & scientific | 2010 |
| Elderberry Brewing Limited | Wholesale & retail | 2012 |
| Electrodiagnostic Services Ltd | Other services | 2018 |
| Elite Car Valeting North East Limited | Wholesale & retail | 2026 |
| Elite Coatings North East Ltd | Construction | 2021 |