| THE Ethical Coaching Company Ltd | Professional & scientific | 2022 |
| THE GFS Initiative CIC | Health & social care | 2025 |
| THE Green PUB (Billy ROW) Limited | Hospitality | 2018 |
| THE Hendy Estate Limited | Administrative & support | 2016 |
| THE Lincoln Consultancy Ltd | Professional & scientific | 2003 |
| THE Little Play Place Ltd | Health & social care | 2025 |
| THE Quarry Tea House Ltd | Hospitality | 2019 |
| THE Red Lion PUB Limited | Hospitality | 2014 |
| THE Three Blue Bells Management Company Limited | Households | 2006 |
| THE Travellers Rest (Crook) Ltd | Hospitality | 2020 |
| THE Vault (Crook) Limited | Hospitality | 2014 |
| THE Vinyl Source Ltd | Manufacturing | 2018 |
| THG North East Ltd | Professional & scientific | 2017 |
| Three Rivers Recruitment Limited | Administrative & support | 2017 |
| Timec 1901 Limited | Extraterritorial | 2025 |
| Tipper Skip Ltd | Extraterritorial | 2010 |
| Tipple Associates Limited | Professional & scientific | 2005 |
| TKL Property Services Ltd | Other services | 2022 |
| TLP the Listening Project CIC | Health & social care | 2025 |
| Togh Limited | Wholesale & retail | 2017 |
| TOM Stencils Ltd | Wholesale & retail | 2025 |
| Top Table Films Ltd | Information & communication | 2018 |
| Tower Surveys 3D Modelling Ltd | Professional & scientific | 2023 |
| Trade Boost Ltd | Information & communication | 2024 |
| Trims Gym Limited | Administrative & support | 1996 |
| Truly Love Hair Academy Ltd | Other services | 2024 |
| Twinkle BEE Equine Limited | Arts & recreation | 2016 |
| Two Valleys Engineering Consultancy Limited | Professional & scientific | 2023 |
| UKI Pizza Crook Ltd | Hospitality | 2026 |
| Unique Driveways N.E Ltd | Construction | 2022 |
| Urban Essentials Ltd | Extraterritorial | 2025 |
| Vaccivets Ltd | Professional & scientific | 2024 |
| Verd Office Solutions Limited | Wholesale & retail | 2011 |
| Victora Software Technology Ltd. | Extraterritorial | 2016 |
| Vitamin Mountain Ltd | Extraterritorial | 2018 |
| Viva Durham NE Limited | Hospitality | 2016 |
| Vortex Lighting Limited | Construction | 2006 |
| W Norton Estates Ltd | Real estate | 2024 |
| W. Marley (Landscape Specialist) Ltd | Administrative & support | 2006 |
| W. Marley Agricultural Contractors Limited | Administrative & support | 1982 |
| Walker & Walker Properties Ltd | Real estate | 2019 |
| Walker Machinery Ltd | Wholesale & retail | 2024 |
| Wear Jammin Studio CIC | Arts & recreation | 2014 |
| Wear Valley Accountancy Ltd | Professional & scientific | 2021 |
| Wear Valley Construction Ltd | Construction | 2023 |
| Wear Valley Rendering Limited | Construction | 2014 |
| Wear Valley Renewables C.I.C. | Energy | 2013 |
| Wear Valley Waste Ltd | Administrative & support | 2006 |
| Weardale Activity Centre Limited | Arts & recreation | 2023 |
| Weardale Building Services Limited | Construction | 2016 |
| Weardale Properties Limited | Real estate | 2013 |
| Weldrack Limited | Wholesale & retail | 2000 |
| West END Garage (Wolsingham) Ltd | Wholesale & retail | 2013 |
| West END PUB Co Limited | Hospitality | 2019 |
| WHC Advisory Ltd | Professional & scientific | 2025 |
| White Hydro Limited | Professional & scientific | 2020 |
| White Magic Group Ltd | Arts & recreation | 2026 |
| Willington and District Angling Club Ltd | Agriculture & fishing | 2018 |
| Willington Pizzeria (NE) Ltd | Hospitality | 2025 |
| Willington PUB Company Ltd | Hospitality | 2025 |
| Willis Brothers Ltd | Transport & logistics | 2021 |
| Willis Scott Group Limited | Professional & scientific | 2024 |
| Wisemove (Holdings) Ltd | Financial services | 2020 |
| Wisemove Land and Property Consultants Limited | Real estate | 2004 |
| Wood & Oliver Limited | Professional & scientific | 2025 |
| Workplace Training & Education Ltd | Education | 2022 |
| Wright Tranz (European) Ltd | Transport & logistics | 2025 |
| Wrights Forestry Services Limited | Agriculture & fishing | 2024 |
| Wright’S Grab N Shift Northwest Ltd | Construction | 2019 |
| Wudland Solutions Ltd | Agriculture & fishing | 2025 |
| Your Local Food & Wine Ltd | Wholesale & retail | 2012 |
| Your Local Property Ltd | Real estate | 2020 |
| ZAK Richard Limited | Information & communication | 2026 |
| Zaksons Limited | Hospitality | 2016 |
| Zedan Traders Ltd | Real estate | 2021 |