| Thompson & Ball Limited | Real estate | 2017 |
| Thornfire Games Ltd | Information & communication | 2023 |
| Thornhill Property Group Limited | Real estate | 2023 |
| Thoroughbred Industrial Doors Limited | Construction | 2000 |
| Thoughtful Design Ltd | Information & communication | 2024 |
| Threading Station Limited | Other services | 2020 |
| Threads by DEE Ltd | Wholesale & retail | 2025 |
| Three Aliens in a Trenchcoat Limited | Information & communication | 2026 |
| Three DEE Media Ltd | Professional & scientific | 2026 |
| Thriftx Ltd | Wholesale & retail | 2025 |
| Thrill Island Ltd | Wholesale & retail | 2020 |
| Thrillsphere Technology Limited | Information & communication | 2025 |
| Thrive Properties & Investments Ltd | Real estate | 2024 |
| Thrive Trading Worldwide Ltd | Wholesale & retail | 2024 |
| Thriving Life Consultancy Limited | Professional & scientific | 2026 |
| Thrivy Ltd | Information & communication | 2019 |
| Throwbacks Xoxo Ltd | Administrative & support | 2024 |
| Thryft Trade Ltd | Wholesale & retail | 2025 |
| Thumped Ltd | Professional & scientific | 2023 |
| Thun Ltd | Real estate | 2023 |
| Thunder Tea Ltd | Hospitality | 2024 |
| Thurayya Ltd | Wholesale & retail | 2025 |
| TI Event Services Ltd. | Information & communication | 2018 |
| TI22 Ltd | Professional & scientific | 2024 |
| Ticket Span Solutions Ltd | Other services | 2024 |
| Tidal ESL Limited | Information & communication | 2025 |
| Tide Media Group Limited | Information & communication | 2025 |
| Tide Radio UK Limited | Information & communication | 2026 |
| Tier 1 Homes Ltd | Real estate | 2022 |
| Tierraorganics Ltd | Wholesale & retail | 2015 |
| Tiffany Badges Limited | Manufacturing | 2003 |
| Tijani Ltd | Wholesale & retail | 2026 |
| Tijaro Ltd | Wholesale & retail | 2024 |
| TIK Commerce Ltd | Wholesale & retail | 2025 |
| Tilt Limited | Professional & scientific | 2023 |
| Timber Yard Residents Ltd | Households | 2021 |
| Time and Place Entertainment Ltd | Hospitality | 2020 |
| Time IS Money (TIM) Ltd | Information & communication | 2025 |
| Time to Question the Rhetoric Limited | Information & communication | 2025 |
| Timeloop Toys CIC | Arts & recreation | 2026 |
| Times Candles Ltd | Manufacturing | 2025 |
| Timi Tims Property Management Ltd | Real estate | 2023 |
| Tinaya Limited | Information & communication | 2026 |
| Tinker AI Limited | Information & communication | 2024 |
| Tinker Trinkets Gifts Ltd | Wholesale & retail | 2025 |
| Tinky Care Ltd | Manufacturing | 2025 |
| Tiny Red Pixel Ltd | Information & communication | 2026 |
| Tipl Ltd | Financial services | 2024 |
| Tirlow Wedding Flowers Ltd | Wholesale & retail | 2024 |
| Tirro Technologies Ltd | Information & communication | 2025 |
| Titanglow Ltd | Wholesale & retail | 2026 |
| Titanvault Ltd | Wholesale & retail | 2026 |
| Tivb Consulting Ltd | Professional & scientific | 2019 |
| Tivix Consultancy Ltd | Information & communication | 2025 |
| TJ Archives Ltd | Wholesale & retail | 2023 |
| TJ Ryleigh Limited | Professional & scientific | 2019 |
| TJA Properties & Investments Ltd | Real estate | 2021 |
| TJM Security Services Ltd | Administrative & support | 2023 |
| TK Euro Commercials Ltd | Wholesale & retail | 2026 |
| TKM Engineering (Gloucester) Ltd | Manufacturing | 2025 |
| Tkoh Limited | Wholesale & retail | 2024 |
| TLB World Group Ltd | Wholesale & retail | 2022 |
| TLJ Commercial Ltd | Households | 2024 |
| Tlpi Limited | Administrative & support | 2016 |
| Tlte C.I.C. | Information & communication | 2025 |
| Tlug Limited | Professional & scientific | 2023 |
| TLY Solutions Ltd | Wholesale & retail | 2018 |
| TM Art Conservation Ltd | Arts & recreation | 2021 |
| Tmcan Limited | Health & social care | 2023 |
| TML Metrics Limited | Professional & scientific | 2021 |
| TMT Roofing and Cladding Ltd | Construction | 2025 |
| TMW Consulting Ltd | Professional & scientific | 2026 |
| TMX Ecommerce Ltd | Wholesale & retail | 2025 |
| TN Education Ltd | Education | 2026 |
| TNE Academy Ltd | Professional & scientific | 2025 |
| Tn’S Speedy Ltd | Construction | 2025 |
| TO BE Honest Ltd | Information & communication | 2020 |
| TO BE Sure Medical Limited | Health & social care | 2012 |
| Toast Ventures Ltd | Information & communication | 2026 |
| Tofer Global Ltd | Wholesale & retail | 2024 |
| Tofr Holdings Limited | Financial services | 2022 |
| Tofululu Trading Co. Ltd | Wholesale & retail | 2025 |
| Together With OUR Friends Ltd | Information & communication | 2023 |
| Togetherway Co Ltd | Wholesale & retail | 2026 |
| Togunova Limited | Information & communication | 2025 |
| TOK Comerence Limited | Wholesale & retail | 2024 |
| Toke Cooks Ltd | Hospitality | 2025 |
| Tokkipop Limited | Wholesale & retail | 2025 |
| Tokora Foods Ltd | Manufacturing | 2025 |
| Tomonmars Ltd | Information & communication | 2025 |
| Tonely AI Ltd | Information & communication | 2025 |
| Tonkin ME Limited | Other services | 2021 |
| Tonshi Creative Limited | Professional & scientific | 2014 |
| Toolstore Marketplace Limited | Information & communication | 2017 |
| Tooth & Bone Investment Group Ltd | Real estate | 2024 |
| Tooth Wisdom Ltd | Education | 2026 |
| Top Marks for Property Limited | Real estate | 2023 |
| Top One Market Ltd | Wholesale & retail | 2026 |
| Top SD Holdings Ltd | Real estate | 2024 |
| Top Sky Ltd | Transport & logistics | 2019 |