| THE Office Massage (TOM) Ltd | Health & social care | 2023 |
| THE Office of Paul Graves Limited | Professional & scientific | 2020 |
| THE Orchids Management Company Limited | Households | 2014 |
| THE Orenda Collective Ltd | Professional & scientific | 2019 |
| THE Paella Company Limited | Wholesale & retail | 2004 |
| THE People's Bricks CIC | Administrative & support | 2025 |
| THE Primrose Centre Limited | Health & social care | 2007 |
| THE Propel Hub Ltd | Administrative & support | 2024 |
| THE Prospect Trust | Education | 2017 |
| THE Psychology LAB Ltd | Professional & scientific | 2019 |
| THE Railway Enthusiasts' Club (REC) Limited | Administrative & support | 2004 |
| THE Rooms Rehearsal Studios Limited | Arts & recreation | 2001 |
| THE Ruby Play Cafe Limited | Hospitality | 2018 |
| THE Safety Training Academy Ltd | Education | 2023 |
| THE Scotts Company Pension Trustee Limited | Professional & scientific | 2018 |
| THE Segen Group Limited | Financial services | 2020 |
| THE Skillset London Ltd | Education | 2026 |
| THE South East Window Cleaners Limited | Administrative & support | 2024 |
| THE Surrey and Hampshire Commercial Window Cleaning Company Ltd | Administrative & support | 2025 |
| THE Tech Galore Limited | Information & communication | 2022 |
| THE Theory Films UK Limited | Information & communication | 2009 |
| THE Three Degrees Tribute Limited | Arts & recreation | 2012 |
| THE Thrive Space Collective Ltd | Professional & scientific | 2025 |
| THE Tree Consultants Ltd | Professional & scientific | 2023 |
| THE Triangle Cafe Limited | Wholesale & retail | 2000 |
| THE Village Physiotherapy Practice Ltd | Health & social care | 2009 |
| THE VW Centre Limited | Wholesale & retail | 2002 |
| THE Wellmount Group Limited | Administrative & support | 2017 |
| Theatre 99 Limited | Education | 2025 |
| Thebarwithin Ltd. | Other services | 2017 |
| Thehomesale Ltd | Information & communication | 2025 |
| Themis Global Limited | Financial services | 2015 |
| Thermoheat Plumbing & Heating Limited | Construction | 2014 |
| Thermosplit Holdings Limited | Information & communication | 2018 |
| Thermosplit Limited | Information & communication | 2016 |
| Think Smart Accounting Services Ltd | Professional & scientific | 2015 |
| Think Smart Accounts Ltd | Professional & scientific | 2004 |
| Think Smart Group Holdings Ltd | Financial services | 2023 |
| Think Smart People Ltd | Administrative & support | 2022 |
| Thomas Anthony Commercial Accountancy Services Ltd | Professional & scientific | 2013 |
| Thomas Electrical Engineering Limited | Construction | 2021 |
| Thor Electrical Services Limited | Construction | 2016 |
| Thorough Events (Holdings) Ltd | Extraterritorial | 2014 |
| Thorough Events Ltd | Administrative & support | 2011 |
| Thread Doctor Services Limited | Wholesale & retail | 2008 |
| Three Unit Management Company Limited | Administrative & support | 1976 |
| Three's Company (Graphic Design) Limited | Arts & recreation | 1979 |
| Thurston Aviation Engineering Limited | Manufacturing | 2015 |
| Thurston Aviation Limited | Manufacturing | 1992 |
| Tiara Beauty & Aesthetics Limited | Other services | 2022 |
| TIM Budgen Illustration Limited | Information & communication | 2015 |
| TIM Parker Ltd | Professional & scientific | 2014 |
| Time City Limited | Information & communication | 2012 |
| Timely Building Supplies Ltd | Wholesale & retail | 2023 |
| Tina Peers Cosmetic Aesthetics Limited | Health & social care | 2011 |
| Tina Peers Medical Services Limited | Health & social care | 2011 |
| Tipbot Ltd | Information & communication | 2023 |
| Tisics Limited | Manufacturing | 2005 |
| Titan Autocare Services UK Limited | Wholesale & retail | 2025 |
| Titan BC Limited | Extraterritorial | 2014 |
| Titanium Consultants Ltd | Professional & scientific | 2010 |
| Titanium Model Management Ltd | Other services | 2017 |
| TJJ Restaurant Ltd | Hospitality | 2019 |
| Tkcs Tsang Company Limited | Real estate | 2026 |
| TKI Living Ltd | Administrative & support | 2025 |
| TKN Restaurant Limited | Hospitality | 2023 |
| TLB Butchers Ltd | Wholesale & retail | 2019 |
| TLM Composites Ltd | Manufacturing | 2016 |
| TLM06 Ltd | Transport & logistics | 2017 |
| Tlsurfer Limited | Professional & scientific | 2023 |
| TM Herald Consulting Ltd | Professional & scientific | 2022 |
| TM Smarter Homes Limited | Administrative & support | 2014 |
| TNT Events Limited | Hospitality | 2025 |
| Tofu Wayne Limited | Wholesale & retail | 2026 |
| TOM Lenthall Limited | Wholesale & retail | 2008 |
| Tommytomitza Ltd | Manufacturing | 2020 |
| Tomo Contractors Ltd | Construction | 2020 |
| Tonje Healthcare Limited | Public administration | 2022 |
| Top Tier Cleaning Ltd | Administrative & support | 2024 |
| Top Tier Consult Ltd | Information & communication | 2024 |
| Topline Solutions Limited | Other services | 2014 |
| Topmark Contractors Limited | Manufacturing | 1997 |
| Topspec Driveways Ltd | Construction | 2009 |
| Toptier Dryliners Ltd | Construction | 2023 |
| Tosh Accountancy Limited | Professional & scientific | 2021 |
| Tosh Media Ltd | Manufacturing | 2025 |
| Total Health Midlands Limited | Health & social care | 2015 |
| Total Integrated Marketing Ltd | Professional & scientific | 2012 |
| Total Services Plumbing and Heating Limited | Construction | 2019 |
| Total Tool & Plant Repair Ltd | Manufacturing | 2021 |
| Tots Events Ltd | Arts & recreation | 2019 |
| Touch Photography Limited | Professional & scientific | 2012 |
| Tourette Syndrome (UK) Association Trading AS Tourettes Action | Information & communication | 1991 |
| Tourist Saver Ltd | Wholesale & retail | 2022 |
| Tower Hill Garage Limited | Wholesale & retail | 2009 |
| Tower View House Ltd | Construction | 2023 |
| Town Heating and Appliances Ltd | Construction | 2023 |
| Trade Team Maintenance Ltd | Administrative & support | 2023 |
| Tradewinds Inns Limited | | 1986 |
| Traditional Hospitality Limited | Hospitality | 2025 |