| Thermoservices Limited | Construction | 2006 |
| Therushs Limited | Wholesale & retail | 2024 |
| Thesas Ltd | Information & communication | 2025 |
| Theshaffinish Ltd | Wholesale & retail | 2024 |
| Thespiceshub Ltd | Hospitality | 2025 |
| Thianet Ltd | Construction | 2025 |
| Thiluu Consulting Ltd | Professional & scientific | 2025 |
| Think Forward Network CIC | Professional & scientific | 2025 |
| Think Global Solutions Limited | Information & communication | 2025 |
| Think Sport Coaching Ltd | Arts & recreation | 2015 |
| Thinkgrc Holdings Ltd | Financial services | 2025 |
| Thinkgrc Ltd | Information & communication | 2025 |
| Thinklusive Solutions Limited | Information & communication | 2019 |
| Thirtys Holding Limited | Information & communication | 2024 |
| Thirumala Limited | Information & communication | 2025 |
| This IS Lagos Ltd | Hospitality | 2026 |
| THL Property Company Limited | Real estate | 2021 |
| Thmc+ Ltd | Construction | 2026 |
| Thomas & Robinson Property LLP | | 2019 |
| Thomas ALL Services Limited | Construction | 2024 |
| Thomas C Holdings Ltd | Real estate | 2026 |
| Thomas Scannell 33 Ltd | Real estate | 2020 |
| Thomas Telecom Company Limited | Information & communication | 2014 |
| Thompson Plastering Ltd | Construction | 2026 |
| Thomson Travel Group (Holdings) Limited | Professional & scientific | 1996 |
| Thornhill Clinic Limited | Health & social care | 2012 |
| Thornrest Properties Ltd | Real estate | 2015 |
| Thornrowe Limited | Construction | 1987 |
| Thoroughbred Motor Company Ltd | Wholesale & retail | 2015 |
| Thousands Mile Ltd | Wholesale & retail | 2021 |
| Thread & Thimble Ltd | Wholesale & retail | 2025 |
| Threads Creatives Limited | Other services | 2020 |
| Threatzero Ltd | Information & communication | 2025 |
| Three Brothers Luton Limited | Wholesale & retail | 2024 |
| Three Brothers PUB Limited | Hospitality | 2025 |
| Three Counties Builders Ltd | Construction | 2016 |
| Three Counties Property Developers Limited | Construction | 2001 |
| Three Counties Roofing and Solar Ltd | Construction | 2026 |
| Three Oaks Bespoke Ltd | Construction | 2024 |
| Three Ways (Herts) Ltd | Construction | 2017 |
| Threesixfiveuk Ltd | Information & communication | 2019 |
| Threesons Hospitality Limited | Hospitality | 2025 |
| Thrive Adhd Ltd | Health & social care | 2026 |
| Thrive Creative Hub CIC | Professional & scientific | 2025 |
| Thrive Fitness Studio Ltd | Arts & recreation | 2026 |
| Thrive Living Care Ltd | Health & social care | 2026 |
| Throttlex Ltd | Wholesale & retail | 2026 |
| Through the Gears Limited | Wholesale & retail | 2024 |
| Throwbox Innovation Studios Limited | Information & communication | 2019 |
| Throwing Plates Limited | Professional & scientific | 2020 |
| THS Accounting and Tax Ltd | Professional & scientific | 2025 |
| Thunder Ride Ltd | Wholesale & retail | 2026 |
| Thunderbell Assets Ltd | Construction | 2025 |
| Thunderful Games Limited | Information & communication | 2004 |
| Thunderhill Limited | Administrative & support | 2000 |
| TI Watchers Limited | Administrative & support | 2025 |
| Tiata Limited | Information & communication | 2011 |
| Tibro Design Limited | | 1976 |
| Ticee Ltd | Wholesale & retail | 2026 |
| Tick Ideas Int'L Limited | Information & communication | 2012 |
| TICK2BUY Mart Ltd | Administrative & support | 2024 |
| Ticket Compensation Ltd. | Financial services | 2015 |
| Tico Car Services Limited | Wholesale & retail | 2023 |
| Ticsa Construct Ltd | Construction | 2023 |
| Tidelink Ltd | Wholesale & retail | 2026 |
| Tidy Car Hire Ltd | Administrative & support | 2026 |
| Tidy Holidays Limited | Other services | 2026 |
| Tier One Property Group Ltd | Hospitality | 2024 |
| Tiermoyle Contract’S Ltd | Construction | 2025 |
| Tierramar Engineering Ltd | Professional & scientific | 2018 |
| Tiffies Bakery Ltd | Hospitality | 2026 |
| TIG Care Limited | Administrative & support | 2023 |
| Tiger 24 Hour Cars Ltd | Transport & logistics | 2014 |
| Tiger Cars Ltd | Transport & logistics | 2010 |
| Tiger K9 Security Service Ltd | Administrative & support | 2021 |
| Tigers Holdings Ltd | Real estate | 2026 |
| Tigga Smile Limited | Health & social care | 2003 |
| Tigga Tano Ltd | Health & social care | 2020 |
| Tijaara Ltd | Wholesale & retail | 2023 |
| Tikandol Favour Limited | Real estate | 2019 |
| Tikfusion UK Ltd | Wholesale & retail | 2025 |
| Tilak Properties Limited | Real estate | 2021 |
| Tile Direct Distribution Ltd | Wholesale & retail | 2021 |
| Tile Direct Outlet Ltd | Wholesale & retail | 2025 |
| Tile Direct Superstore Limited | Wholesale & retail | 2025 |
| Tillomed Laboratories Limited | Wholesale & retail | 1990 |
| Tilly Construction & Refurbishment Ltd | Construction | 2022 |
| TIM & ED Ltd | Hospitality | 2024 |
| TIM & Francisca Enterprise Limited | Wholesale & retail | 2024 |
| TIM Blake Projects Limited | Arts & recreation | 2025 |
| TIM Construct Ltd | Construction | 2017 |
| Timba Global Ltd | Construction | 2022 |
| Timber Sash Direct Limited | Administrative & support | 2011 |
| Timbershield Treatment Limited | Manufacturing | 2026 |
| Time and Travel Limited | Financial services | 2015 |
| Time for Pubs Ltd | Hospitality | 2011 |
| Time in RO Ltd | Hospitality | 2016 |
| Time to Glow Ltd | Other services | 2024 |
| TIMEDESIGN51 Limited | Professional & scientific | 2009 |
| Timefood Ltd | Hospitality | 2025 |