| Teddies Tots Nursery Limited | Health & social care | 2019 |
| Teddy Bear's Tea Party Limited | Wholesale & retail | 2016 |
| Teddy Roman FBA Ltd | Wholesale & retail | 2025 |
| TEE Line Ltd | Manufacturing | 2021 |
| Teebossmay Ltd | Wholesale & retail | 2023 |
| Teen Threads C.I.C. | Other services | 2024 |
| Teen Yaar Limited | Real estate | 2023 |
| Tees River Limited | Financial services | 2015 |
| Teeside Investments Ltd | Real estate | 2022 |
| Teesside Car Centre Limited | Wholesale & retail | 2018 |
| Teethex Limited | Health & social care | 2019 |
| Tegrove Limited | Information & communication | 2015 |
| TEH & Partners Ltd | Real estate | 2019 |
| Tekinnovations UK Limited | Information & communication | 2011 |
| Teknexa Ltd | Information & communication | 2023 |
| Teknowledge Ltd | Information & communication | 2012 |
| Telecom Resource Ltd | Administrative & support | 2015 |
| Telecom Solutions Resource Limited | Information & communication | 2013 |
| Telemarketing Services Ltd | Professional & scientific | 2019 |
| Telesto Ltd | Information & communication | 2024 |
| Tell & Tell Ltd | Transport & logistics | 2020 |
| Tempro Recruitment Limited | Professional & scientific | 2026 |
| Tempsford Court Management Company Limited | Households | 1964 |
| TEN Development Advisory Limited | Construction | 2025 |
| Tenacity Productions Limited | Information & communication | 2001 |
| Tenby Imports & Exports Ltd | Wholesale & retail | 2003 |
| Tenkm Healthcare Ltd | Health & social care | 2021 |
| Tenten B2B Ltd | Administrative & support | 2026 |
| Tententen Consulting Limited | Administrative & support | 2014 |
| Tepsi Limited | Hospitality | 2024 |
| Teraheat Ltd | Construction | 2016 |
| Terasia Limited | Real estate | 2017 |
| Terek Icon Ltd | Wholesale & retail | 2024 |
| Termpark Management (Hocroft Court) Limited | Households | 1976 |
| Terra Global Commerce Ltd | Wholesale & retail | 2025 |
| Terra Tasks Limited | Professional & scientific | 2024 |
| Terra Trans Ltd | Transport & logistics | 2023 |
| Terrafirma Engineering Limited | Professional & scientific | 2021 |
| Terranueva Development Limited | Information & communication | 2014 |
| Terre Invest LP | | 2021 |
| Terries Creative Cakery Ltd | Hospitality | 2016 |
| Tersely Estates Limited | Real estate | 2018 |
| Teshni Property Services Ltd | Real estate | 2022 |
| Teshuvah Limited | Information & communication | 2019 |
| Teskolo Holding LP | | 2017 |
| Tesla JS Construction Ltd | Construction | 2011 |
| Tesora Technologies Limited | Information & communication | 2021 |
| Tessell IT Solutions Limited | Information & communication | 2012 |
| Tessellex Ltd | Professional & scientific | 2017 |
| Test Elite Ltd | Information & communication | 2021 |
| Testaq Consultancy Limited | Administrative & support | 2015 |
| Testing Incorp Ltd | Information & communication | 2024 |
| Testrade Limited | Professional & scientific | 1971 |
| Tevamor Limited | Professional & scientific | 2015 |
| Textech Traders Ltd | Wholesale & retail | 2021 |
| Textile Care Ltd | Other services | 2025 |
| Textile Tune Limited | Professional & scientific | 2024 |
| Teyvika Nari Productions Limited | Information & communication | 2026 |
| TF Composites Ltd | Manufacturing | 2011 |
| Tfab Consulting Limited | Information & communication | 2013 |
| TG Auto Repairs Limited | Wholesale & retail | 2026 |
| TG Contracts Limited | Administrative & support | 2022 |
| TG Damp Limited | Administrative & support | 2025 |
| TG Main Limited | Administrative & support | 2025 |
| TGA Express Ltd | Transport & logistics | 2025 |
| Tgbcs Ltd | Professional & scientific | 2019 |
| Tgme UK Ltd | Water & waste | 2012 |
| TGS Design and Build Ltd | Construction | 2021 |
| TH Motorsport LLP | | 2016 |
| TH Motorsport Watford Limited | Wholesale & retail | 2004 |
| Thaa Limited | Professional & scientific | 2018 |
| Thaci Property Ltd | Real estate | 2022 |
| Thame Property Company LLP | | 2012 |
| Thames Architectural Metalwork Limited | Extraterritorial | 2014 |
| Thames Global Advisors Ltd | Administrative & support | 2025 |
| Thames Interiors Ltd | Construction | 2022 |
| Thames Projects Limited | Administrative & support | 2001 |
| Thames Valet DRY Cleaners Limited | Other services | 2026 |
| Thames Valley Cultural Centres Limited | Education | 1974 |
| Thana Engineering Ltd | Construction | 2026 |
| Thanakarn Enterprises Ltd | Professional & scientific | 2016 |
| Tharma UK Ltd | Health & social care | 2012 |
| Tharoo Consulting Limited | Information & communication | 2015 |
| That's Dead Nice Ltd | Information & communication | 2025 |
| That's My Name Limited | Wholesale & retail | 2017 |
| That's Still Rape Ltd | Other services | 2025 |
| Thaxted Dental Centre Limited | Health & social care | 2006 |
| THE Accent Centre Ltd | Education | 2022 |
| THE Acupuncturists Ltd | Health & social care | 2008 |
| THE Albion Soap Company Limited | Professional & scientific | 1893 |
| THE Althusserian Centre (London) Limited | Information & communication | 2025 |
| THE Aquamarine Centre Ltd | Other services | 2017 |
| THE ARC Phoundation Limited | Administrative & support | 2007 |
| THE ARK Community Church | Other services | 2009 |
| THE Association of Learned and Professional Society Publishers | Administrative & support | 2000 |
| THE Association of Woodturners of Great Britain | Education | 2012 |
| THE Atrato Foundation | Other services | 2022 |
| THE Atticism Limited | Professional & scientific | 2021 |
| THE Auger Foundation | Other services | 2004 |
| THE Bald FX Trader Limited | Professional & scientific | 2022 |