| Tabula Network Ltd | Information & communication | 2025 |
| Tactical Survey Group Limited | Professional & scientific | 2007 |
| Tactical Survey Solutions Ltd | Information & communication | 2017 |
| Tactical Survey Systems Limited | Administrative & support | 2007 |
| TAG Transport (Europe) Limited | Transport & logistics | 2013 |
| Taha Traders Ltd | Other services | 2019 |
| Taku Properties Limited | Real estate | 2024 |
| Tala & Maya Limited | Wholesale & retail | 2007 |
| Talent Barbers Ltd | Other services | 2016 |
| Talent Nexus Ltd | Professional & scientific | 2014 |
| Tall Short Property Ltd | Real estate | 2025 |
| Talwar Traders Ltd | Wholesale & retail | 2019 |
| Tangou Consultancy Ltd | Information & communication | 2024 |
| Tangou Properties Ltd | Real estate | 2025 |
| Tanos Construction Ltd | Construction | 2019 |
| Tapf Limited | Wholesale & retail | 2002 |
| Taqueria LA Salsa Limited | Hospitality | 2025 |
| TAS Consultancy Limited | Professional & scientific | 2019 |
| Tash Consulting Ltd | Professional & scientific | 2018 |
| Tasha Design Ltd | Professional & scientific | 2020 |
| Tasker Consultancy Limited | Professional & scientific | 2011 |
| Tasty House London Ltd | Hospitality | 2025 |
| Tatt 2 International Limited | Information & communication | 2017 |
| Tawfiq Limited | Health & social care | 2023 |
| Taxi Mimi CAB Ltd | Transport & logistics | 2025 |
| TBB Universal Logistics UK Ltd | Wholesale & retail | 2012 |
| Tdcleaning 777 Ltd | Administrative & support | 2015 |
| TDD Projects Ltd | Real estate | 2024 |
| Teadd Ltd | Information & communication | 2022 |
| Teakdale Limited | Real estate | 2024 |
| Tech IT Consultants (UK) Ltd | Information & communication | 2019 |
| Tech PR Stars Ltd | Information & communication | 2017 |
| Tech Savvy Studios Ltd | Information & communication | 2025 |
| Tech Trailblazers Limited | Professional & scientific | 2014 |
| Techbar Systems Ltd | Information & communication | 2017 |
| Techbritannia Limited | Professional & scientific | 2014 |
| Technet Communications Ltd | Information & communication | 2015 |
| Technique Network Services Ltd | Information & communication | 2007 |
| Technoz Ltd | Manufacturing | 2023 |
| Teci Ltd | Wholesale & retail | 2025 |
| Tedilux Jewellery Ltd | Manufacturing | 2025 |
| Tedy Ltd | Other services | 2004 |
| TEE and JAY Nail Spa Ltd | Other services | 2025 |
| Teecdesigns Ltd | Professional & scientific | 2023 |
| Teeth and More Limited | Health & social care | 2024 |
| Tejano Loco Ltd | Hospitality | 2020 |
| Telia International AB | | 1991 |
| Tellytechs Ltd | Information & communication | 2023 |
| Tembusu Property Limited | Real estate | 2023 |
| TEN Foot Giant Ltd | Professional & scientific | 2013 |
| Tenancy Cleaning Nationwide Ltd | Administrative & support | 2023 |
| Tenant Strategies Limited | Real estate | 1994 |
| Tendx Ltd | Financial services | 2025 |
| Tennis Avenue Limited | Arts & recreation | 2002 |
| Tennis Avenue School Ltd | Education | 2020 |
| Tennistogether Limited | Arts & recreation | 2002 |
| Tennyson Maintenance Limited | Real estate | 2023 |
| TEQ IT Ltd | Information & communication | 2018 |
| Teresa Scognamiglio Limited | Manufacturing | 2019 |
| Terly Ltd | Real estate | 2022 |
| Tesa Creation Ltd | Real estate | 2020 |
| Test Infinity Ltd | Information & communication | 2023 |
| Tether Limited | Extraterritorial | 2022 |
| Tevver Ltd | Wholesale & retail | 2025 |
| Textron Industries Limited | Other services | 2022 |
| TGB Building Ltd | Construction | 2021 |
| Tggp Limited | Other services | 2022 |
| Thames Electrical Solutions Ltd | Construction | 2017 |
| Thank Evans Limited | Administrative & support | 2002 |
| Thannam Club Limited | Wholesale & retail | 2025 |
| Thapa & Sons Limited | Wholesale & retail | 2025 |
| Tharai Ltd | Construction | 2007 |
| Thayani Ltd | Wholesale & retail | 2020 |
| THE 365 Trade Group Limited | Construction | 2018 |
| THE Arena (London) Ltd | Real estate | 2026 |
| THE Avenue Residents' Management Company Limited | Households | 1997 |
| THE B17 Charitable Trust | Other services | 1999 |
| THE Blue Arrow Care Group Limited | Health & social care | 2022 |
| THE Bridge Communications Limited | Information & communication | 2005 |
| THE Cave Co-Operative Ltd | Professional & scientific | 2009 |
| THE Chase Club Ltd | Wholesale & retail | 2025 |
| THE Cleaning White Company "Crystal" Limited | Administrative & support | 2020 |
| THE Clinitial Group Ltd | Information & communication | 2020 |
| THE Close Day Nursery Opco Ltd | Professional & scientific | 2017 |
| THE Close Day Nursery Propco Ltd | Real estate | 2017 |
| THE Cloud Works 360 Limited | Information & communication | 2013 |
| THE Coffee Bay Company Limited | Hospitality | 2002 |
| THE Company MAN Ltd | Information & communication | 2022 |
| THE Crowley Partnership Limited | Administrative & support | 2007 |
| THE Daialogue Ltd | Wholesale & retail | 2020 |
| THE Daily Jaws Limited | Information & communication | 2021 |
| THE Daily Jaws Products and Merchandise Limited | Wholesale & retail | 2025 |
| THE Digitalize Solution Ltd | Information & communication | 2024 |
| THE Dog Spot Ltd | Other services | 2026 |
| THE Douglas Centre Trust | Other services | 1995 |
| THE Ember Learning Trust | Education | 2016 |
| THE Emperor's Old Clothes Ltd | Manufacturing | 2021 |
| THE FD Studio London Limited | Professional & scientific | 2018 |
| THE Flying Colour Company Post Production Limited | Information & communication | 2013 |
| THE French Touch Physio Ltd | Health & social care | 2019 |