| Top Grade Limited | Other services | 2015 |
| Top London Lofts Ltd | Construction | 2018 |
| Top Motors Limited | Wholesale & retail | 2024 |
| Top OIL Products Limited | Wholesale & retail | 1985 |
| Top Plan Care Services Ltd | Health & social care | 2023 |
| Top Score Holdings Limited | Financial services | 2024 |
| Top Star Service and Engineering Limited | Construction | 2024 |
| Top Supports Estate Agent Ltd | Real estate | 2008 |
| Top Wasters Ltd | Water & waste | 2019 |
| Topfinish Property Management Ltd | Construction | 2024 |
| Topland Properties Ltd | Real estate | 2025 |
| Topmanremoval Ltd | Transport & logistics | 2024 |
| Topteam Construction Ltd | Construction | 2023 |
| Topwatch-Tech Security Ltd | Administrative & support | 2023 |
| Torekon Medical Consulting Ltd | Wholesale & retail | 2025 |
| Torekon Properties Ltd | Real estate | 2024 |
| Toriilondon Limited | Wholesale & retail | 2021 |
| Toru Beds Ltd | Wholesale & retail | 2016 |
| Toss-Uk CIC | Administrative & support | 2023 |
| Total Auto Care Solutions Ltd | Wholesale & retail | 2026 |
| Total Care London Limited | Health & social care | 2022 |
| Total Control Security Services Ltd | Administrative & support | 2020 |
| Total Decorations (Essex) Ltd | Construction | 2014 |
| Total Lifting Services Limited | Administrative & support | 2020 |
| Totems Services Ltd | Health & social care | 2019 |
| Touch of Elysium Limited | Other services | 2025 |
| Tourem Ltd | Administrative & support | 2017 |
| Tovik Ltd | Construction | 2026 |
| Tower of Grace Church of ALL Nations Limited | Administrative & support | 2010 |
| Towers Trading Limited | Wholesale & retail | 2015 |
| Towin Ventures Limited | Professional & scientific | 2008 |
| Toxel Ltd | Wholesale & retail | 2023 |
| Toxys Foods Limited | Hospitality | 2025 |
| Toziongate Limited | Administrative & support | 2024 |
| Tpic Accounting Solutions Limited | Professional & scientific | 2014 |
| TPM Group Holdings Ltd | Real estate | 2026 |
| TPN Estates Limited | Real estate | 2023 |
| TPP Construction Ltd | Construction | 2016 |
| TPP Solutions Ltd | Professional & scientific | 2023 |
| TR Commerce Ltd | Other services | 2025 |
| Trac Office Equipment Limited | Wholesale & retail | 1984 |
| Track Transport Limited | Transport & logistics | 2024 |
| Trackview Global Resources Limited | Other services | 2024 |
| Trade ANG Ltd | Transport & logistics | 2022 |
| Trade X BGD UK Limited | Other services | 2024 |
| Trader Auto Ltd | Wholesale & retail | 2025 |
| Traderspk Cars Ltd | Wholesale & retail | 2024 |
| Tradid Ltd | Wholesale & retail | 2021 |
| Trading Deals Master Limited | Wholesale & retail | 2016 |
| Trading DEN Ltd | Wholesale & retail | 2021 |
| Trading Group Limited | Administrative & support | 2020 |
| Traditional Delights Ltd | Hospitality | 2024 |
| Traedy Limited | Wholesale & retail | 2025 |
| Training Spot Ltd | Education | 2020 |
| Trainly Limited | Education | 2025 |
| Trandvee Ltd | Real estate | 2020 |
| Trans Alliance Investments Limited | Professional & scientific | 2018 |
| Trans Alpine Logistics Ltd | Other services | 2020 |
| Transatlantic Traders Ltd | Wholesale & retail | 2022 |
| Transebi Limited | Transport & logistics | 2016 |
| Transeft Ltd | Transport & logistics | 2020 |
| Transfer & Logistics Brothers Ltd | Professional & scientific | 2023 |
| Transforming Lives Company Ltd | Health & social care | 2009 |
| Travel Tranquility Limited | Hospitality | 2025 |
| Travelfinders Group Ltd | Transport & logistics | 2024 |
| Treble O Herbs Ltd | Health & social care | 2022 |
| Treble O Properties Ltd | Real estate | 2025 |
| Tree MR Ltd | Professional & scientific | 2018 |
| Treetales Ltd | Wholesale & retail | 2025 |
| Trendhive Global Ltd | Wholesale & retail | 2025 |
| Trendify Shop Ltd | Wholesale & retail | 2026 |
| Trendy Finds Ltd | Wholesale & retail | 2023 |
| Trendylabels Limited | Wholesale & retail | 2025 |
| Trendynamic Ltd | Wholesale & retail | 2024 |
| Trensey Limited | Wholesale & retail | 2025 |
| Tres Jolie Limited | Wholesale & retail | 2014 |
| Treswall Business Services Ltd | Administrative & support | 2025 |
| TRH Traders Ltd | Wholesale & retail | 2024 |
| Tribe of Judah Security Limited | Education | 2020 |
| Tribune Publishing Limited | Information & communication | 2018 |
| Tricore Services Ltd | Administrative & support | 2025 |
| Trigger Consult Ltd | Professional & scientific | 2020 |
| Trijema Healthcare Limited | Health & social care | 2024 |
| Trillionex Ltd | Professional & scientific | 2020 |
| Trilltraining Ltd | Education | 2025 |
| Trinity Care Consultancy Limited | Administrative & support | 2023 |
| Trinity Omega Ltd | Real estate | 2025 |
| Trinity Playcentre Ltd | Education | 2003 |
| Trio FAM Ltd | Administrative & support | 2026 |
| Trio's Hair Removal Solutions Ltd | Other services | 2019 |
| Trip Home Properties Limited | Real estate | 2026 |
| Triple a Driving School Ltd | Education | 2025 |
| Triple a Heating Ltd | Construction | 2023 |
| Triple Access Limited | Wholesale & retail | 2022 |
| Triple M Care Solution Ltd | Health & social care | 2025 |
| Triple O'S Services Ltd | Health & social care | 2023 |
| Triple Property Investments Ltd | Real estate | 2024 |
| Triple R With Limited | Construction | 2024 |
| Triple T&T Recruitment Limited | Administrative & support | 2025 |
| Triplehub Limited | Information & communication | 2016 |