| Summers Financial Services (NE) Ltd | Financial services | 2017 |
| Summers Property LLP | | 2017 |
| Sunderland Dental Equipment Ltd | Other services | 2007 |
| Supernode Technology Limited | Manufacturing | 2023 |
| Sureheat Plumbing and Heating N.E. Ltd | Construction | 2010 |
| Surjan's Fish & Chips Limited | Hospitality | 2024 |
| Sustainable Community Enterprises North East Ltd | Administrative & support | 2012 |
| Swaledale Convenience Store Ltd | Wholesale & retail | 2020 |
| Swift Renewables Yorkshire Ltd | Construction | 2023 |
| T & B Access Limited | Construction | 2025 |
| Tailored Blinds Ltd | Manufacturing | 2015 |
| Tait Fire and Security Limited | Administrative & support | 2024 |
| TAM Scaffolding Limited | Construction | 2020 |
| Tanfield Protective Products Ltd | Administrative & support | 2010 |
| Tasteofgreek Ltd | Hospitality | 2021 |
| Taylor & Wood Publishing Ltd | Information & communication | 2022 |
| Taylor Made Catering Ltd | Hospitality | 2011 |
| Taylor's Lets Ltd | Real estate | 2026 |
| Teakisi CIC | Information & communication | 2020 |
| Team Training Group Limited | Education | 2024 |
| Terry Technologies Ltd | Information & communication | 2015 |
| Textadapt Limited | Information & communication | 1998 |
| Tharsus Direct Limited | Manufacturing | 2005 |
| Tharsus Group Limited | Manufacturing | 2012 |
| Tharsus Limited | Manufacturing | 2007 |
| THE Adventures of Compost Limited | Information & communication | 2021 |
| THE Beauty Factory (N.E.) Limited | Other services | 2005 |
| THE Boutique Dog Hotel Limited | Agriculture & fishing | 2025 |
| THE Coastal Rejuvenation Clinic NE Ltd | Other services | 2024 |
| THE Cosy PAW Cafe Ltd | Hospitality | 2025 |
| THE Food Hub Blyth Limited | Hospitality | 2026 |
| THE Harbour Hatch Ltd | Hospitality | 2024 |
| THE Hideaway Bureau Ltd | Hospitality | 2025 |
| THE Honest Diver Limited | Wholesale & retail | 2020 |
| THE Needles Development Limited | Construction | 2018 |
| THE Polished Genie Ltd | Other services | 2026 |
| THE Primal Way Community Interest Company | Other services | 2025 |
| THE Princess Pavilion Ltd | Arts & recreation | 2023 |
| THE Roller Door Company North East Ltd | Construction | 2026 |
| THE Wood Heating Company (Biomass) Ltd | Construction | 2010 |
| THE Woodfuel Centre CIC | Manufacturing | 2007 |
| Thea Elizabeth Studio Ltd | Wholesale & retail | 2022 |
| Thea Elizabeth Weddings and Gifts Ltd | Wholesale & retail | 2025 |
| Thirteen Properties Limited | Real estate | 2006 |
| Thomas Fuel Injection Services (North East) Limited | Wholesale & retail | 2013 |
| Thomas Knight Care Home Limited | Health & social care | 2010 |
| Thomas Peck Hunter Property Group Ltd | Real estate | 2025 |
| Thompson & Thompson Consultancy Ltd | Manufacturing | 2018 |
| Thompson Access Solutions Ltd | Construction | 2022 |
| Thompson Group 365 Limited | Construction | 2016 |
| Thompson's Builders Ltd | Construction | 2022 |
| Thornton Storage Ltd | Transport & logistics | 2019 |
| Timec 1864 Limited | Financial services | 2024 |
| Timestep Activity Centre Ltd | Arts & recreation | 2024 |
| Tiny Empire Estate Management Ltd | Households | 2024 |
| Tip-Tech Site Machining Solutions Ltd | Manufacturing | 2015 |
| TL Multimedia Limited | Information & communication | 2012 |
| Tmech Services Ltd | Mining & quarrying | 2025 |
| TMG Leisure Ltd | Arts & recreation | 2025 |
| TMG Lettings Ltd | Real estate | 2022 |
| TOK Auto Solution Limited | Wholesale & retail | 2026 |
| Tolbimnif Limited | Extraterritorial | 2022 |
| Tom's Views Limited | Health & social care | 2018 |
| Top Grub Limited | Hospitality | 2023 |
| Top House Bar Ltd | Hospitality | 2025 |
| Tope Riley Limited | Real estate | 2025 |
| Tower Services (Blyth) Limited | Construction | 2018 |
| Towers Homes Limited | Real estate | 2022 |
| Trackrite Exhausts Limited | Manufacturing | 2024 |
| Traildog Events Ltd | Arts & recreation | 2019 |
| Travis Crossborder Ltd | Wholesale & retail | 2026 |
| Triple Eight Developments Ltd | Construction | 2026 |
| Triton Inspections Ltd | Professional & scientific | 2017 |
| True NE Properties Ltd | Real estate | 2026 |
| Truenorth Energy Ltd | Construction | 2025 |
| Tuhu 85 Limited | Other services | 2022 |
| Turkish Barbers Blyth Ltd | Other services | 2023 |
| Turnbull Energy Consulting Limited | Professional & scientific | 2020 |
| Tyler Marine Ltd | Manufacturing | 2021 |
| Tyneside Tech Ltd | Information & communication | 2023 |
| Uhlan Limited | Wholesale & retail | 2022 |
| UK Vinyl Memories Ltd | Wholesale & retail | 2016 |
| Ultimate Luxury Prizes Ltd | Arts & recreation | 2025 |
| Union Street MOT Centre Limited | Wholesale & retail | 2022 |
| Universal Wolf Limited | Manufacturing | 1997 |
| Uptown Paws Boutique Ltd | Other services | 2020 |
| Urban Land Estates Limited | Construction | 2025 |
| Vanto Group Limited | Professional & scientific | 2026 |
| Vape Junction Blyth Ltd | Wholesale & retail | 2022 |
| Vbds Gourmet Ltd | Hospitality | 2024 |
| Velux Commercial Uk&I Limited | Manufacturing | 2001 |
| Versatile Automation Limited | Professional & scientific | 2024 |
| Versatile Newco Limited | Manufacturing | 2024 |
| VIC Tuff Support Engineering Limited | Professional & scientific | 2003 |
| Vitesh UK Ltd | Wholesale & retail | 2014 |
| Volkscentre Ltd | Wholesale & retail | 2019 |
| Voltel Digital Limited | Information & communication | 2022 |
| Voltel IT Ltd | Information & communication | 2024 |
| Voncar Ltd | Hospitality | 2026 |
| Vprabh(Tw) Ltd | Hospitality | 2026 |