| Tote Media Limited | Information & communication | 2013 |
| Tote UK International Limited | Arts & recreation | 2004 |
| Totepool Limited | Arts & recreation | 2004 |
| Totesport Limited | Arts & recreation | 2004 |
| Totum Consulting Limited | Professional & scientific | 2025 |
| Touche Comms Limited | Administrative & support | 2013 |
| Touchline Properties Ltd | Households | 2016 |
| Tourism Exchange Great Britain Limited | Information & communication | 2021 |
| Tourism Exchange Ltd | Financial services | 2022 |
| Tower Associates International Limited | Information & communication | 1999 |
| Tower Associates LLP | | 2025 |
| Towergate Investments Limited | Real estate | 2020 |
| Towner Logistics Services Limited | Administrative & support | 2023 |
| Townley & Co Limited | Professional & scientific | 2014 |
| Townley Group Ltd | Administrative & support | 2021 |
| TP Marketing Ltd | Professional & scientific | 2025 |
| Tpaas Ltd | Professional & scientific | 2023 |
| Tpara Holdings Limited | Financial services | 2025 |
| TPC Global Ltd | Education | 2023 |
| TPC Therapy Limited | Health & social care | 2015 |
| Tpcmanagementsolutions Ltd | Professional & scientific | 2025 |
| TPE Solutions Ltd | Administrative & support | 2026 |
| TPG the Project Group Ltd | Information & communication | 2008 |
| TPH Consultancy Ltd | Administrative & support | 2014 |
| Tpia Consultancy Ltd | Real estate | 2023 |
| Tpia Services Ltd | Real estate | 2025 |
| TPM Brickwork 2025 Limited | Construction | 2025 |
| TPM Brickwork Limited | Construction | 2019 |
| Tpna Holdings Limited | Professional & scientific | 2020 |
| Tpna Investments Limited | Professional & scientific | 2020 |
| TPS Ceramic Ltd | Manufacturing | 2025 |
| TPT Motive Ltd | Administrative & support | 2025 |
| TQS Accountancy Solutions Ltd | Professional & scientific | 2008 |
| TR & L Cooper Ltd | Agriculture & fishing | 2007 |
| TR Engineering Services Limited | Professional & scientific | 2016 |
| TRA Jain Limited | Health & social care | 2022 |
| Trabelsi Ltd | Administrative & support | 2025 |
| Traceline Solutions Limited | Professional & scientific | 2019 |
| Track Force Recruitment Limited | Administrative & support | 2016 |
| TRACK2GREEN Consulting Ltd | Information & communication | 2025 |
| Trackwork Sollutions Ltd. | Administrative & support | 2014 |
| Tradacc Ltd | Professional & scientific | 2019 |
| Trade & Connect Ltd | Wholesale & retail | 2024 |
| Trade Fabrication Systems Limited | Manufacturing | 1998 |
| Trade Glass Supplies Limited | Manufacturing | 1986 |
| Trade Mart Limited | Wholesale & retail | 2023 |
| Trade Tnote Futures Ltd | Financial services | 2023 |
| Tradeframe 1 Ltd | Wholesale & retail | 2020 |
| Tradeframe Holdings Limited | Financial services | 2024 |
| Tradeframe NW Limited | Manufacturing | 2009 |
| Tradegears (Components) Ltd. | Wholesale & retail | 1998 |
| Tradereach UK Limited | Wholesale & retail | 2019 |
| Tradesilver Ltd | Construction | 2026 |
| Trading & Consolidation Company (TCC) Limited | Wholesale & retail | 2021 |
| Traditional Building & Roofing Ltd | Construction | 2022 |
| Traditions Hair Limited | Other services | 2015 |
| Traditions Sandwiches Ltd | Hospitality | 2008 |
| Trafficom Limited | Extraterritorial | 2022 |
| Trafford Projects Limited | Administrative & support | 2013 |
| Trafford Property Limited | Real estate | 2019 |
| Trafford Veterinary Centre Limited | Professional & scientific | 2002 |
| Trailertec UK Limited | Wholesale & retail | 2015 |
| Train Systems Engineering Ltd | Professional & scientific | 2019 |
| Trainer Properties Limited | Real estate | 2016 |
| Training for Electricians Ltd. | Administrative & support | 2021 |
| Trakmatix Limited | Manufacturing | 2022 |
| Trand Trading Ltd | Wholesale & retail | 2025 |
| Tranformiq Consulting Ltd | Professional & scientific | 2026 |
| Tranquil Garden Rooms Ltd | Construction | 2017 |
| Transact Bowden Ltd | Construction | 2025 |
| Transanalytical Holdings Limited | Professional & scientific | 2026 |
| Transanalytical Services Limited | Professional & scientific | 2019 |
| Transcendent Consulting Services Limited | Information & communication | 2016 |
| Transform Estates Limited | Real estate | 2024 |
| Transform Solutions Limited | Professional & scientific | 2022 |
| Transformation Coaching (Warrington) Limited | Arts & recreation | 2021 |
| Transformd Ltd | Professional & scientific | 2023 |
| Transformed Health Care Services Ltd | Administrative & support | 2019 |
| Transforming Words Limited | Professional & scientific | 2016 |
| Transformu Ltd | Arts & recreation | 2024 |
| Transition 365 Limited | Information & communication | 2017 |
| Transitionwise Ltd | Professional & scientific | 2024 |
| Transorient Global Logistics Ltd | Extraterritorial | 2014 |
| Transparent Transport Ltd | Transport & logistics | 2022 |
| Transport Impact Consulting Limited | Administrative & support | 2015 |
| Transport Training Hub Limited | Education | 2023 |
| Transportation Infrastructure Group Limited | Professional & scientific | 2005 |
| Tranzform Talent Consultancy Ltd | Administrative & support | 2024 |
| Traumatech Ltd | Manufacturing | 1973 |
| Travel Trade Executive Limited | Extraterritorial | 2006 |
| Travel Trade Recruitment (Holdings) Limited | Professional & scientific | 2019 |
| Travel Trade Recruitment Limited | Administrative & support | 2001 |
| Travellers' ST. Christopher Ltd | Real estate | 2023 |
| Travelogix Limited | Information & communication | 2011 |
| Travelogix Ventures Limited | Information & communication | 2018 |
| Travelogix Ventures Trustee Limited | Financial services | 2025 |
| Travers Consulting Group Limited | Professional & scientific | 2022 |
| Traverse Associates Limited | Information & communication | 2007 |
| Travis Property Investment Ltd | Real estate | 2019 |
| TRB Building Control Consultants Ltd | Administrative & support | 2025 |