| THE Punjabi Society of British Isles Ltd | Health & social care | 2016 |
| THE Qcurb Group Ltd | Construction | 2017 |
| THE Quad-Centenary Club LLP | | 2016 |
| THE Quiet Light Ltd | Information & communication | 2026 |
| THE Rainbow Therapy Practice Ltd | Health & social care | 2018 |
| THE Richmond Town Tavern Limited | Hospitality | 2016 |
| THE Roofing Partnership Limited | Construction | 2023 |
| THE Roseland Distilling Company Limited | Manufacturing | 2019 |
| THE Russetts Management Company Limited | Households | 1988 |
| THE Shoulder Practice Ltd | Health & social care | 2022 |
| THE Sidhu Corporation Limited | Real estate | 2021 |
| THE Substantial Club Ltd | Wholesale & retail | 2019 |
| THE Superuser Group Ltd | Information & communication | 2022 |
| THE Swedish Pouch Company Ltd | Wholesale & retail | 2020 |
| THE Tides Inn Woolacombe Limited | Hospitality | 2009 |
| THE Tranquillity Coach Limited | Other services | 2024 |
| THE Two ST. James Trust | Other services | 2006 |
| THE Vietnamese Kitchen (Soho) Limited | Hospitality | 2010 |
| THE Vietnamese Kitchen Ltd | Hospitality | 2009 |
| THE Vietnamese Kitchens (Property) Limited | Extraterritorial | 2011 |
| THE White Cliff Food Company Limited | Wholesale & retail | 2016 |
| There for Everything Ltd | Professional & scientific | 2011 |
| Thinking 5.0 Ltd | Administrative & support | 2025 |
| Third Republic Limited | Administrative & support | 2014 |
| Third Rock Consulting Limited | Professional & scientific | 2012 |
| Thorneminster Limited | Real estate | 1987 |
| Thorpe House School Trust | Education | 1985 |
| Three Trees Enterprise Ltd | Financial services | 2025 |
| TI Brands Ltd | Administrative & support | 2010 |
| Ticcle Ltd | Wholesale & retail | 2026 |
| Tides of Time Pictures Ltd | Information & communication | 2020 |
| Tienda Property Ltd | Professional & scientific | 2016 |
| Tikarius Ltd | Financial services | 2025 |
| Tilted Pictures Limited | Other services | 2014 |
| Timber Cross Construction Limited | Construction | 2010 |
| Timecode Solutions Ltd | Information & communication | 2025 |
| Timecode Systems Limited | Information & communication | 2010 |
| Times House Ltd | Professional & scientific | 2026 |
| Tims Dairy Ltd | Manufacturing | 1984 |
| TJ Brothers Retail Limited | Wholesale & retail | 2025 |
| TJ Pro Tiling Limited | Other services | 2019 |
| Tmdfh Ltd | Other services | 2020 |
| TNC Media Holdings Ltd | Administrative & support | 2017 |
| TO Dine for Catering Limited | Hospitality | 2012 |
| TO XL Consulting Limited | Other services | 1999 |
| Toadim Ltd | Real estate | 2023 |
| Tokki Group Ltd | Hospitality | 2023 |
| Tokyo Autos UK Ltd | Wholesale & retail | 2023 |
| TOM Bevan Coaching Ltd | Health & social care | 2026 |
| TOM Brown Limited | Hospitality | 2024 |
| TOM Daxon Limited | Wholesale & retail | 2010 |
| Tom's Table Limited | Hospitality | 2022 |
| Toner Mechanical & Electrical Ltd | Construction | 2012 |
| Tonroe Group (Nominees) Limited | Financial services | 2026 |
| Tonroe Group Limited | Professional & scientific | 2002 |
| Tonsley (Birkenshaw NO.2) Ltd | Extraterritorial | 2013 |
| Tonsley (Birkenshaw) Ltd | Extraterritorial | 2013 |
| Tonsley (Strathclyde NO.2) Ltd | Extraterritorial | 2012 |
| Tonsley (Strathclyde) Ltd | Extraterritorial | 2012 |
| Tonsley (Worcester NO.2) Ltd | Extraterritorial | 2015 |
| Tonsley (Worcester NO.3) Ltd | Professional & scientific | 2017 |
| Tonsley (Worcester) Ltd | Extraterritorial | 2015 |
| Tonsley (York NO.2) Ltd | Extraterritorial | 2015 |
| Tonsley (York) Ltd | Extraterritorial | 2015 |
| Tonsley Investments Limited | Real estate | 2007 |
| Top of the World Travel Ltd | Administrative & support | 2025 |
| Torchlight Consulting Ltd | Professional & scientific | 2026 |
| Torcross Consulting Ltd | Professional & scientific | 2025 |
| Torminster Limited | Real estate | 1949 |
| Toro Negro Limited | Professional & scientific | 2016 |
| Torogatama Ltd | Real estate | 2023 |
| Totallycommitted Limited | Information & communication | 2019 |
| Tovs Limited | Administrative & support | 1997 |
| Toy Studio Limited | Professional & scientific | 2022 |
| Tppi (Holdings) Ltd | Manufacturing | 2014 |
| Trade Right Home Improvements Ltd | Construction | 2025 |
| Tradebridge Limited | Financial services | 1994 |
| Tradebridge Management Ltd | Professional & scientific | 2021 |
| Tradex Ltd | Information & communication | 2007 |
| Trafalgar Ventures Limited | Professional & scientific | 2015 |
| Trakai Limited | Information & communication | 2017 |
| Transform and Grow Limited | Information & communication | 2025 |
| Transform Cars London Limited | Transport & logistics | 2010 |
| Transform This Ltd | Professional & scientific | 2024 |
| Travanex Travels Ltd | Information & communication | 2021 |
| Travejar Ltd | Administrative & support | 2025 |
| Travellots Ltd | Administrative & support | 2026 |
| Travelshaw Services Limited | Administrative & support | 1983 |
| Treasury Consulting Limited | Professional & scientific | 2025 |
| Tregunter Limited | Professional & scientific | 2012 |
| Tremarne Properties Limited | Real estate | 2025 |
| Triangle Surgical Limited | Wholesale & retail | 2015 |
| Triassic Developments Limited | Construction | 1984 |
| Trident Quality Solutions Limited | Professional & scientific | 2025 |
| Triple a Mortgages Limited | Financial services | 2024 |
| Triton S.Bucks Limited | Real estate | 2011 |
| Trobe Studios Limited | Professional & scientific | 1959 |
| Trotter Independent Traders Limited | Extraterritorial | 2025 |
| TRP Property Development Ltd | Construction | 2021 |
| TRP Skip Hire Ltd | Water & waste | 2021 |