| Teamzara Properties Ltd | Real estate | 2024 |
| Teaspoon Holdings Limited | Financial services | 2024 |
| Tecare Homecare Limited | Other services | 2025 |
| Tech & the Beancounters Ltd | Professional & scientific | 2016 |
| Tech Performance Partners Ltd | Professional & scientific | 2025 |
| Techaiml Ltd | Information & communication | 2023 |
| Techloop Solutions Limited | Professional & scientific | 2025 |
| Technical Maintenance Training Limited | Administrative & support | 2008 |
| Technofy Ltd | Professional & scientific | 2021 |
| Technologos Ltd | Information & communication | 2024 |
| Technology Connectivity Solutions Ltd | Construction | 2024 |
| Technology International (Europe) Limited | Professional & scientific | 1987 |
| Technology International (Japan) Limited | Professional & scientific | 2004 |
| Technoquip Limited | Wholesale & retail | 2014 |
| Techpol Limited | Manufacturing | 2002 |
| Techquest Limited | Information & communication | 2017 |
| Techramp Ltd | Information & communication | 2024 |
| Techspective Ltd | Information & communication | 2010 |
| Techturf Technologies Ltd | Information & communication | 2022 |
| Teckollab Ltd | Information & communication | 2022 |
| Teckstone Limited | Information & communication | 2009 |
| Tecohms Limited | Information & communication | 2022 |
| Tecomatic Limited | Information & communication | 2021 |
| TED Financial Services Limited | Financial services | 2023 |
| TED Norris Consultancy Ltd. | Financial services | 2016 |
| Teddy Lemon Limited | Professional & scientific | 2025 |
| Tedi Speed Ltd | Transport & logistics | 2026 |
| TEE Singh Ltd | Information & communication | 2024 |
| TEE Travels Ltd | Information & communication | 2026 |
| Tee-Care Limited | Health & social care | 2019 |
| Teedammy Healthcare Limited | Health & social care | 2019 |
| Teejaja Limited | Health & social care | 2022 |
| Teekayprojects Ltd | Construction | 2015 |
| Tegra Accounting Limited | Professional & scientific | 2012 |
| Tekhs Services Limited | Information & communication | 2020 |
| Tekno Care Services Ltd | Health & social care | 2019 |
| Telecell Ltd | Information & communication | 2013 |
| Teleco Services Ltd | Information & communication | 2024 |
| Teleglobal Consulting Ltd | Information & communication | 2009 |
| Telenco UK Limited | Information & communication | 2020 |
| Teleport With Helency Ltd | Information & communication | 2025 |
| Tema Global Consultancy Ltd | Professional & scientific | 2026 |
| Templequay Property Investments Limited | Real estate | 2021 |
| Templeton Associates Limited | Professional & scientific | 2011 |
| Tenant Screening Limited | Administrative & support | 2010 |
| Tenfold (Swindon) Ltd. | Construction | 1997 |
| Tennyson Investments Limited | Wholesale & retail | 2004 |
| Teo's Caffe & Bistro Limited | Hospitality | 2022 |
| Teoxane UK Limited | Wholesale & retail | 2005 |
| Tera Punjab Ltd | Hospitality | 2025 |
| Terasprint Limited | Manufacturing | 2019 |
| Teres Health Ltd | Health & social care | 2018 |
| Teres Properties Ltd | Real estate | 2022 |
| Teriot Commercial Ltd | Real estate | 2021 |
| Terminal 2 Studios Ltd | Information & communication | 2025 |
| Terra IQ (UIL) Limited | Information & communication | 2026 |
| Terra IQ Limited | Information & communication | 2025 |
| Terrestrial Systems Limited | Extraterritorial | 2017 |
| Terro-Tech Limited | Information & communication | 2016 |
| TES Roofing Ltd | Construction | 2020 |
| Tesito Investment Group Limited | Real estate | 2018 |
| Testsmarter Limited | Information & communication | 2018 |
| Tetbury Kebab Van Ltd | Hospitality | 2026 |
| Tetelestai London Ltd | Health & social care | 2025 |
| Tetimo Ltd | Wholesale & retail | 2024 |
| Tetoys Recycling Ltd | Wholesale & retail | 2023 |
| Tetronics Holdings Limited | Professional & scientific | 2004 |
| Tetronics Technologies Limited | Manufacturing | 2020 |
| Tewkesbury Maine Ltd | Other services | 2018 |
| Texblue Limited | Wholesale & retail | 2011 |
| Text Global Limited | Administrative & support | 2015 |
| TF Comms Limited | Information & communication | 2004 |
| TFC Pizza Ltd | Hospitality | 2025 |
| Tffs Ltd | Hospitality | 2019 |
| TFM Publishing Limited | Information & communication | 1997 |
| TG Jones High Street Holdings Limited | Professional & scientific | 2008 |
| TG Jones High Street Limited | Wholesale & retail | 2008 |
| TG Universal UK Limited | Arts & recreation | 2025 |
| Tgls Holdings Ltd | Real estate | 2024 |
| TGM Technology Ltd | Professional & scientific | 2025 |
| Tgtc Limited | Wholesale & retail | 2022 |
| TGV Barbers Ltd | Other services | 2023 |
| TGV Projects Limited | Financial services | 2018 |
| Thadia Ltd | Manufacturing | 2023 |
| Thai Blue Peacock Limited | Hospitality | 2024 |
| Thai Express Retail Limited | Hospitality | 2012 |
| Thai House Spa Limited | Other services | 2023 |
| Thaihousestreetfoods Ltd | Hospitality | 2025 |
| Thain Garden Rooms Ltd | Administrative & support | 2016 |
| Thames Bookkeeping Limited | Professional & scientific | 2007 |
| Thames Logistics and Sales Ltd | Wholesale & retail | 2018 |
| Thames Valley ENT Ltd | Health & social care | 2025 |
| Thames Valley Operators Community Interest Company | Administrative & support | 2005 |
| Thamesdown Blinds Limited | Manufacturing | 2025 |
| Thamesdown Coachworks Ltd | Manufacturing | 2022 |
| Thamesdown Heating Ltd | Construction | 2026 |
| Thamesdown Marketing Partners LLP | | 2015 |
| Thamesdown Recycling Holdings Limited | Financial services | 2025 |
| Thamesdown Recycling Limited | Water & waste | 2022 |
| Thamesdown Roofing Contractors Limited | | 1982 |