| Teesside Gravity Consultancy Ltd | Professional & scientific | 2026 |
| Teesside Hand Car Wash Ltd | Administrative & support | 2017 |
| Teesside Healthcare Limited | Health & social care | 1996 |
| Teesside High School Enterprises Limited | Wholesale & retail | 2007 |
| Teesside Interiors Ltd | Wholesale & retail | 2019 |
| Teesside International (North) Limited | Construction | 2019 |
| Teesside Jointing Services Limited | Manufacturing | 2024 |
| Teesside Leisure Services Ltd | Transport & logistics | 2017 |
| Teesside Leisure Solutions Ltd | Wholesale & retail | 2023 |
| Teesside Magnetics Limited | Professional & scientific | 2023 |
| Teesside Media School Ltd | Professional & scientific | 2019 |
| Teesside Mortar and Concrete Ltd | Manufacturing | 2022 |
| Teesside Personnel Ltd | Administrative & support | 2019 |
| Teesside Polishing Ltd | Administrative & support | 2024 |
| Teesside Property Estates Limited | Real estate | 2021 |
| Teesside Property Projects Ltd | Real estate | 2025 |
| Teesside Psychological Therapy Service Limited | Health & social care | 2025 |
| Teesside Rapid Transport Ltd | Transport & logistics | 2024 |
| Teesside Renewable Services Ltd | Professional & scientific | 2019 |
| Teesside Renewable Solutions Ltd | Construction | 2024 |
| Teesside Rental Apartments Ltd | Real estate | 2021 |
| Teesside Roofing & Cladding Ltd | Construction | 2022 |
| Teesside Sales Consultants Ltd | Wholesale & retail | 2019 |
| Teesside Taping Contractors Limited | Construction | 2008 |
| Teesside Vehicle Rental Ltd | Wholesale & retail | 2025 |
| Teesside Wellbeing IVS and Aesthetics Ltd | Other services | 2024 |
| Teessideautos Ltd | Wholesale & retail | 2023 |
| Teessidefireinstalls Ltd | Construction | 2023 |
| Teessside Property (Stockton) Ltd | Real estate | 2020 |
| Teesvalley Interiors Ltd | Construction | 2020 |
| Teesworks Netting Co Ltd | Manufacturing | 2025 |
| Teethtalk Ltd | Health & social care | 2023 |
| Tegomart Limited | Wholesale & retail | 2025 |
| Teide Inspection Ltd | Professional & scientific | 2026 |
| Tekgem (UK) Limited | Information & communication | 2005 |
| Telenor Group Ltd | Wholesale & retail | 2025 |
| Temp-Team Limited | Administrative & support | 1987 |
| Temptec Ltd | Administrative & support | 2025 |
| Tenant-Finders Teesside Ltd | Real estate | 2017 |
| Tennant Street Medical Practice LLP | | 2013 |
| Tepmas Limited | Professional & scientific | 2016 |
| Terenki Global Limited | Construction | 2025 |
| Tersus Property Solutions Ltd | Real estate | 2025 |
| Test-Track-Monitor Limited | Professional & scientific | 2020 |
| TG Stevenson Property Ltd | Real estate | 2023 |
| Tgcj Services Ltd | Construction | 2024 |
| TH Power Generation Ltd | Professional & scientific | 2026 |
| Thai 2 Go NE Ltd | Hospitality | 2022 |
| Thapyay Ltd | Real estate | 2025 |
| That Decor Company Ltd | Administrative & support | 2020 |
| Thats Group Limited | Information & communication | 2016 |
| THC by Better Days Ltd | Administrative & support | 2023 |
| THE 19TH Hole Golf SIM Hub Limited | Wholesale & retail | 2026 |
| THE ARK Care Principles Limited | Health & social care | 2015 |
| THE Artique Boutique Ltd | Hospitality | 2025 |
| THE Ashbank Group Limited | Other services | 1970 |
| THE Association of Professional Researchers and Academicians (the Apra) | Education | 2020 |
| THE Baby Care Academy Ltd | Education | 2021 |
| THE Beauty Lane (NE) Ltd | Other services | 2024 |
| THE Beth Fisher Academy Ltd | Education | 2019 |
| THE Blackwell OX Limited | Hospitality | 2004 |
| THE Book Dragon Limited | Wholesale & retail | 2024 |
| THE Bowburn Pharmacy Company Limited | Wholesale & retail | 1994 |
| THE Bridge Coffee House Limited | Hospitality | 2001 |
| THE Buccaneer (Middlesbrough) Ltd | Hospitality | 2019 |
| THE Burger Cart Limited | Hospitality | 2025 |
| THE Cable Crew Limited | Information & communication | 2001 |
| THE Catwalk Academy Ltd | Arts & recreation | 2015 |
| THE Centre for Financial Capability | Education | 2020 |
| THE Chief MRS Global Group Limited | Wholesale & retail | 2025 |
| THE Club. RP Limited | Arts & recreation | 2024 |
| THE Colliery Ltd | Professional & scientific | 2004 |
| THE Content Creation Company Ltd | Information & communication | 2016 |
| THE Creative Quad CIC | Real estate | 2023 |
| THE D Project Dance Company Limited | Education | 2024 |
| THE Dark Lounge Ltd | Hospitality | 2025 |
| THE Dispensary Barr Ltd | Hospitality | 2026 |
| THE Dispensary Stockton Ltd | Hospitality | 2024 |
| THE Divers TAP Ltd | Hospitality | 2026 |
| THE DON WAR Memorial Museum & Veterans Hub CIC | Arts & recreation | 2019 |
| THE Double J Group Limited | Wholesale & retail | 2023 |
| THE Drop Brand Ltd | Wholesale & retail | 2023 |
| THE Financial Partnership Estate Planning Limited | Financial services | 2010 |
| THE Fire Place Takeaway Ltd | Hospitality | 2019 |
| THE Five Lamps Organisation | Information & communication | 1989 |
| THE Floating Jeweller Ltd | Manufacturing | 2025 |
| THE Flower BEE Florist & Events Ltd | Wholesale & retail | 2020 |
| THE Flying Geese Leadership and Development Company Ltd | Professional & scientific | 2020 |
| THE Food Safety Training Company Limited | Hospitality | 2013 |
| THE Fresh Meat Team Limited | Hospitality | 2025 |
| THE Freya Edit Ltd | Wholesale & retail | 2025 |
| THE FRY Guys NE Ltd | Hospitality | 2025 |
| THE FUN Jungle Ltd | Arts & recreation | 2019 |
| THE Garage Teesside Ltd | Wholesale & retail | 2018 |
| THE Gcsez Company Limited | Education | 2025 |
| THE George Altrincham Ltd | Hospitality | 2023 |
| THE George PUB & Grill Ltd | Hospitality | 2018 |
| THE Getaway Lounge Limited | Information & communication | 2018 |
| THE Goshen Trust | Professional & scientific | 2007 |
| THE Grab MAN Ltd | Water & waste | 2014 |