| TH Pharmaceutical Limited | Wholesale & retail | 2023 |
| TH4 Ltd | Wholesale & retail | 2016 |
| Thai House Newcastle Ltd | Hospitality | 2016 |
| Thai Massage Gosforth Ltd | Health & social care | 2025 |
| Thalkat Projects Ltd | Information & communication | 2023 |
| Thames Trains Limited | Professional & scientific | 1995 |
| Thames Travel (Wallingford) Limited | Transport & logistics | 2001 |
| Thames Vintage Ltd | Manufacturing | 2014 |
| Thamesdown Transport Limited | Professional & scientific | 1986 |
| Thao's Kitchen Ltd | Hospitality | 2026 |
| Thapar Consulting Limited | Professional & scientific | 2015 |
| That MAC Chap Ltd | Information & communication | 2016 |
| That ODD LOT Limited | Wholesale & retail | 2025 |
| Thaw River Solar Limited | Energy | 2020 |
| THD Commercial Limited | Professional & scientific | 2021 |
| THE -B- Workout Ltd | Arts & recreation | 2022 |
| THE 21 Osborne Road Jesmond Management Company Limited | Hospitality | 2004 |
| THE 3 Shiekhs Ltd | Hospitality | 2019 |
| THE 5TH Avenue Newcastle Limited | Other services | 2017 |
| THE ABC Project (Attitudes Behaviour Consequences) Limited | Education | 2011 |
| THE Accidental Florist Ltd | Wholesale & retail | 2022 |
| THE Acorns Residents Management Company Limited | Households | 2017 |
| THE Acres (Bedlington) Management Company Limited | Households | 2015 |
| THE Actors Forge: Simworks Ltd | Arts & recreation | 2026 |
| THE Adheen Traders Ltd | Wholesale & retail | 2017 |
| THE Adventurers Drinks Company Ltd | Wholesale & retail | 2021 |
| THE Aerosector Group Limited | Professional & scientific | 2025 |
| THE Aesthetic Standard Clinic Ltd | Other services | 2025 |
| THE Aesthetics Lounge Redcar Ltd | Other services | 2020 |
| THE AI Effect Ltd | Information & communication | 2023 |
| THE Alchemists (Northern) Limited | Professional & scientific | 2002 |
| THE Algorithm People Limited | Information & communication | 2018 |
| THE Ancient Unicorn Bar Ltd | Hospitality | 2025 |
| THE Angelou Centre | Hospitality | 1993 |
| THE ARC Property Fund Limited Partnership | | 2007 |
| THE Arch at Craster Limited | Hospitality | 2025 |
| THE ARK Firm Limited | Real estate | 2022 |
| THE Art Factory (N E) Limited | Wholesale & retail | 2012 |
| THE Art of Sole Ltd | Wholesale & retail | 2015 |
| THE Artisan Travel Company Limited | Administrative & support | 2002 |
| THE Arweinydd's Photography Limited | Professional & scientific | 2019 |
| THE Aspens (Birtley) Limited | Real estate | 2017 |
| THE Associate Law Firm Limited | Professional & scientific | 2008 |
| THE Auxilium Society CIC | Administrative & support | 2022 |
| THE Avenue (Acklam) Residents Management Company Limited | Real estate | 2025 |
| THE Avenue (Medburn) Limited | Construction | 2022 |
| THE Avenue (Medburn) Residents Management Company Limited | Households | 2019 |
| THE Awans Newcastle Ltd | Real estate | 2023 |
| THE Bailieborough Company Ltd | Financial services | 2023 |
| THE Bake Butcher Ltd | Wholesale & retail | 2024 |
| THE Bake Durham Ltd | Hospitality | 2025 |
| THE Bake Eldon Ltd | Hospitality | 2026 |
| THE Bake Express Ltd | Hospitality | 2015 |
| THE Bake Newcastle Ltd | Hospitality | 2021 |
| THE Bake One Gosforth Ltd | Hospitality | 2019 |
| THE Balloon Public House Ltd | Hospitality | 2018 |
| THE Balti and Pizza Masters Ltd | Hospitality | 2016 |
| THE Basement NCL Ltd | Wholesale & retail | 2025 |
| THE Bayhorse Inn at Stamfordham Ltd | Hospitality | 2012 |
| THE Beaches Developments Ltd | Real estate | 2025 |
| THE Beat Suite Limited | Information & communication | 2004 |
| THE Beaute Lounge Newcastle Limited | Other services | 2025 |
| THE Beeches Benton RTM Company Limited | Households | 2020 |
| THE Beeches Group Ltd | Professional & scientific | 2020 |
| THE Belsay Trust | Real estate | 2012 |
| THE Bench Play Ltd | Information & communication | 2024 |
| THE Benign OIL Company Limited | Extraterritorial | 1991 |
| THE Benton Wokery Ltd | Hospitality | 2025 |
| THE Berrys Group Limited | Wholesale & retail | 2026 |
| THE BID BUS Ltd | Professional & scientific | 2024 |
| THE Bigger Picture Agency Ltd | Professional & scientific | 2014 |
| THE Bigger Scene Limited | Professional & scientific | 2003 |
| THE Black Candle Company of Northumberland Limited | Wholesale & retail | 2018 |
| THE Blagdon Farm Shop Limited | Wholesale & retail | 2002 |
| THE Blair Wind Project Ltd | Construction | 2023 |
| THE Bloom Project Services Limited | Financial services | 2018 |
| THE Blooming Garden NE Ltd | Wholesale & retail | 2022 |
| THE Blue Hare Therapies Ltd | Health & social care | 2017 |
| THE Blue Star Newcastle Ltd | Hospitality | 2025 |
| THE Boathouse Restaurants Ltd | Hospitality | 2025 |
| THE Boiler Co North East Ltd | Construction | 2022 |
| THE Boneyard Hairdressing Ltd | Other services | 2023 |
| THE Boost Clinic Ltd | Health & social care | 2021 |
| THE Bout Office Limited | Arts & recreation | 2026 |
| THE Braag CIC | Information & communication | 2020 |
| THE Bradford Property Trust Limited | Professional & scientific | 1989 |
| THE Brannigan Family Company Limited | Real estate | 2007 |
| THE Bread Machine Limited | Hospitality | 2026 |
| THE Briganti Group Limited | Financial services | 2022 |
| THE British Association of Critical Care Nurses | Other services | 2001 |
| THE British Electrical & Manufacturing Company Limited | Wholesale & retail | 1937 |
| THE Broadband Computer Company Limited | Information & communication | 2005 |
| THE Brothers Ellios Ltd | Information & communication | 2023 |
| THE Brow Alchemist Ltd | Other services | 2025 |
| THE Brue Foundation | Education | 2012 |
| THE Brunton Deli Ltd | Hospitality | 2009 |
| THE Build Paradox Ltd | Information & communication | 2025 |
| THE Building Maintenance Company Limited | Construction | 2006 |
| THE Bull Beaumaris Limited | Extraterritorial | 2015 |
| THE Bundle Company Limited | Wholesale & retail | 2020 |