| Topcrop Farming Limited | Agriculture & fishing | 2015 |
| Topdealsuk Ltd | Wholesale & retail | 2024 |
| Topguard Services Limited | Other services | 2007 |
| Topham Family Investments Limited | Extraterritorial | 1998 |
| Topland Couriers Limited | Water & waste | 2026 |
| Topline Auto Group Ltd | Wholesale & retail | 2025 |
| Topline Builders Ltd | Construction | 2025 |
| Topmarkes Care Limited | Administrative & support | 2022 |
| Topnotch Joinery (East Anglia) Ltd | Construction | 2006 |
| Toppings Fast Food (UK) Ltd | Hospitality | 2019 |
| Toprys Ltd | Transport & logistics | 2021 |
| Topteam Logistics Ltd | Transport & logistics | 2025 |
| Topteam Properties Ltd | Real estate | 2024 |
| Topteam Technologies Ltd | Information & communication | 2023 |
| Tortoise Property Limited | Real estate | 2006 |
| Tortuga Rail Limited | Transport & logistics | 2013 |
| Torunski Property Ltd | Real estate | 2020 |
| Toscano Services Ltd | Hospitality | 2024 |
| Tosellbuy Cars Limited | Wholesale & retail | 2022 |
| Total Car Care Services Ltd | Wholesale & retail | 2021 |
| Total Car Tech Ltd | Wholesale & retail | 2025 |
| Total Care Options Ltd | Administrative & support | 2017 |
| Total Care Resources Ltd | Health & social care | 2023 |
| Total Cars Ltd | Wholesale & retail | 2023 |
| Total Circuit Solutions Limited | Wholesale & retail | 2011 |
| Total Coaching Solutions Limited | Professional & scientific | 2003 |
| Total Connect Academy CIC | Education | 2026 |
| Total Framing Contractors Ltd | Construction | 2023 |
| Total Health Care Clinics Limited | Health & social care | 2008 |
| Total Health Properties Ltd | Real estate | 2022 |
| Total Healthcare Limited | Health & social care | 2019 |
| Total Home Improvements Peterborough Ltd | Construction | 2023 |
| Total Property Improvements Ltd | Construction | 2025 |
| Total Titan Holdings Limited | Real estate | 2022 |
| Totally Tanned Limited | Other services | 2001 |
| TOTALLY247 Limited | Administrative & support | 2006 |
| Totaltrust Services Ltd | Professional & scientific | 2024 |
| Totax Cleaning Solutions Ltd | Administrative & support | 2023 |
| Totek Limited | Construction | 2022 |
| Touati Express Ltd | Hospitality | 2024 |
| Touch of Class Gifts Limited | Wholesale & retail | 2005 |
| Tour 2 Event Security Limited | Administrative & support | 2022 |
| Tourmajor Limited | Professional & scientific | 1979 |
| Touthill Development Ltd | Real estate | 2014 |
| Touthill Management Ltd | Real estate | 2016 |
| TOW Assist UK Ltd | Wholesale & retail | 2025 |
| TOW Away Recoveries Ltd | Wholesale & retail | 2025 |
| Tow-Fit Ltd | Professional & scientific | 2018 |
| Tower Properties (Peterborough) Limited | Real estate | 2014 |
| Townfast Limited | Construction | 1997 |
| Towngate Space Solutions Ltd | Real estate | 2017 |
| Towngate Tyres and Service Centre Limited | Wholesale & retail | 2014 |
| Townsend Holdings Limited | Financial services | 2016 |
| Townsend Property Enterprises Limited | Administrative & support | 2016 |
| Toy Haven Ltd | Wholesale & retail | 2026 |
| Toy Village Ltd | Wholesale & retail | 2026 |
| Toymaison Ltd | Other services | 2026 |
| TP Select Limited | Administrative & support | 2025 |
| Tpap Ltd | Real estate | 2026 |
| TPJ Supplies Ltd | Wholesale & retail | 2016 |
| TPL Shopfitters Limited | Extraterritorial | 2004 |
| TPW Supplies Ltd | Wholesale & retail | 2024 |
| TQ Takeaway Limited | Hospitality | 2019 |
| TR Consultants (UK) Limited | Professional & scientific | 2002 |
| Trabiz Fusion Ltd | Wholesale & retail | 2024 |
| Track Day Addicts Ltd | Wholesale & retail | 2024 |
| Tracked Shovel Hire Ltd | Administrative & support | 2025 |
| Tracks Publishing Ltd. | Information & communication | 1999 |
| Tracktsw Ltd | Information & communication | 2026 |
| Trade 2 YOU Ltd | Wholesale & retail | 2021 |
| Trade Accelerator Limited | Professional & scientific | 2024 |
| Trade Accelerator UNI Limited | Administrative & support | 2022 |
| Trade Digital Limited | Professional & scientific | 2023 |
| Trade Finance Limited | Professional & scientific | 2022 |
| Trade Frames Holdings Limited | Professional & scientific | 2006 |
| Trade Group Recruitment Limited | Professional & scientific | 2022 |
| Trade Group Services Limited | Other services | 2025 |
| Trade Grow Ltd | Professional & scientific | 2022 |
| Trade International Ltd. | Wholesale & retail | 2007 |
| Trade Marks Cars Ltd | Wholesale & retail | 2020 |
| Trade Mastermind Limited | Administrative & support | 2017 |
| Trade Parcels Ltd | Manufacturing | 2025 |
| Trade Portal (Software) Limited | Information & communication | 2024 |
| Trade Price Roller Shutters Limited | Manufacturing | 2022 |
| Trade Van Sales Limited | Wholesale & retail | 2012 |
| Tradelink Services (2023) Ltd | Construction | 2023 |
| Tradelink Services Limited | Construction | 1991 |
| Tradelivery Limited | Transport & logistics | 2025 |
| Tradewave Ecom Technologies Ltd | Wholesale & retail | 2025 |
| Tradewinds Integrated Services Ltd | Real estate | 2025 |
| Tradewise AI Solutions Ltd | Information & communication | 2026 |
| Traditional Pools Holdings Limited | Administrative & support | 2023 |
| Traditional Pools Limited | Administrative & support | 2007 |
| Traditional Wall Panelling Ltd | Manufacturing | 2021 |
| Tradiusuk Limited | Administrative & support | 2025 |
| Trafiboo Supplies Ltd | Wholesale & retail | 2025 |
| Trailbound Ltd | Manufacturing | 2025 |
| Trailer Vision Ltd | Wholesale & retail | 2010 |
| Training Tips Ltd | Information & communication | 2023 |
| TRAINS4U Limited | Wholesale & retail | 2004 |