| THE Landings Residents Management Company Limited | Households | 2024 |
| THE London Picture Company Limited | Extraterritorial | 1981 |
| THE Maples (Bewdley) Management Company Limited | Households | 2024 |
| THE MID Cheshire Society of Model Engineers Limited | Arts & recreation | 1991 |
| THE Mobile Dipecvim Ltd | Professional & scientific | 2023 |
| THE Mount Consultancy Ltd | Professional & scientific | 2025 |
| THE Next Door (NE) Ltd | Real estate | 2017 |
| THE Oaks (Morpeth) PT Limited | Households | 2025 |
| THE Old Beeston Market Properties Management Limited | Households | 2020 |
| THE Opendoor GIN Company Ltd | Wholesale & retail | 2016 |
| THE Orchards (Bunbury) Limited | Real estate | 2019 |
| THE Orchards (Upton Snodsbury) Management Company Limited | Households | 2021 |
| THE Oval (Selly Oak) Management Company Limited | Households | 2015 |
| THE Paddocks (Aintree) Management Company Limited | Households | 2018 |
| THE Paddocks (Highworth) Management Company Limited | Households | 2018 |
| THE Pastures (Farington Moss) Residents Management Company Limited | Households | 2020 |
| THE Pastures (Lowton) Management Company Limited | Households | 2018 |
| THE Pauper and the Hare Limited | Information & communication | 2025 |
| THE Pavilions Resident Management Company Limited | Households | 2020 |
| THE Poppies (Llay) Residents Management Company Limited | Households | 2024 |
| THE Publishing and Licensing Agency Limited | Arts & recreation | 2002 |
| THE Saddle Fit Academy Ltd. | Education | 2024 |
| THE Sandstone Ridge Trust | Other services | 2011 |
| THE Skeleton Key Liverpool Ltd | Construction | 2021 |
| THE Skylarks (Loughborough) Residents Management Company Limited | Households | 2020 |
| THE Slim Collective Limited | Health & social care | 2026 |
| THE Stress and Trauma Centre Limited | Health & social care | 2013 |
| THE Thundersprint Limited | Arts & recreation | 1997 |
| THE Tirley Garth Company Limited | Real estate | 2002 |
| THE Transformer Lifestyle Company Ltd | Financial services | 2016 |
| THE UGC Consultancy Limited | Professional & scientific | 2023 |
| THE Western Saddler Ltd | Wholesale & retail | 2013 |
| THE Wood Shoot Limited | Arts & recreation | 2022 |
| THE Woodlands Residential Management Company Limited | Households | 2022 |
| Thefrozendivide Ltd | Professional & scientific | 2018 |
| Therisem Company Limited | Households | 2019 |
| Thiele Holdings Limited | Real estate | 1981 |
| Thistledowns Management Company Limited | Households | 2023 |
| Thnxcya Limited | Arts & recreation | 2013 |
| Thomason & Ritchie Equine Ltd. | Professional & scientific | 2014 |
| Thomcons Limited | Information & communication | 2016 |
| Thorn House Management Company Limited | Administrative & support | 1989 |
| Thornton Apartment Block (the Oaks) Resident Management Company Limited | Households | 2020 |
| Threapwood Aviation Services Limited | Professional & scientific | 2014 |
| Tilpad Limited | Real estate | 1996 |
| Timko Limited | Wholesale & retail | 1998 |
| Tiny MAN Ltd | Information & communication | 2019 |
| TJC Consulting Ltd | Professional & scientific | 2025 |
| TOM Chester Limited | Information & communication | 2012 |
| Tommy Limited | Extraterritorial | 2008 |
| TOR View (Castle Cary) Management Company Limited | Households | 2026 |
| Total Contact Equine Solutions Limited | Manufacturing | 2021 |
| Total Synthesis Limited | Manufacturing | 2016 |
| Toucan Estates Limited | Construction | 2021 |
| Tracer Electrical Services Ltd | Wholesale & retail | 2001 |
| Tradekitchens.Com Limited | Wholesale & retail | 2025 |
| Trading Consultants Limited | Real estate | 1990 |
| Transformation for Veterans | Other services | 2010 |
| Transport&Training Ltd | Administrative & support | 2022 |
| Trending Tides Ltd | Professional & scientific | 2023 |
| Trevalyn Place (Rossett) Management Company Ltd | Households | 2024 |
| Trinity Choice Limited | Extraterritorial | 2022 |
| Trinity Fields (Winsford) Management Company Limited | Households | 2017 |
| Tripseal Security Ltd | Manufacturing | 2019 |
| Trstmgt Holdings Limited | Financial services | 2019 |
| Trust Eco Energy Limited | Other services | 2021 |
| Trustbng Limited | Other services | 2021 |
| Trustgreen (BD) Limited | Other services | 2021 |
| Trustgreen (Commercial) Limited | Other services | 2021 |
| Trustgreen (ESG) Limited | Other services | 2021 |
| Trustgreen (Group) Limited | Financial services | 2015 |
| Trustgreen (Legal) Limited | Other services | 2021 |
| Trustgreen (PT) Limited | Other services | 2013 |
| Trustgreen (RFS) Limited | Other services | 2016 |
| Trustgreen (RFS01) Services Limited | Other services | 2020 |
| Trustgreen (RFS2) Limited | Other services | 2024 |
| Trustgreen (Stewardship) Limited | Other services | 2017 |
| Trustgreen Services Limited | Administrative & support | 2024 |
| Trustmgt (South West) Limited | Other services | 2021 |
| Trustmgt Properties Limited | Other services | 2018 |
| Trustnation CIC | Extraterritorial | 2014 |
| Trustpump Limited | Other services | 2021 |
| Tudor Branding Limited | Professional & scientific | 2015 |
| Turbo Tracks Ltd | Arts & recreation | 2026 |
| Tushingham Properties Ltd | Financial services | 2024 |
| Tutbury Park Residents Management Company Limited | Households | 2025 |
| Twilight Lighting Solutions Ltd | Construction | 2017 |
| Twill Meadow Residents Management Company Limited | Households | 2026 |
| Twin Treatments Ltd | Other services | 2021 |
| TY Bach Limited | Households | 1990 |
| TY Parc Limited | Administrative & support | 2003 |
| Tyddyn Bach (Llaingoch) Residents Management Company Limited | Households | 2021 |
| Type of Null Limited | Wholesale & retail | 2025 |
| Ugcbar&Catering Ltd | Hospitality | 2026 |
| UK for Good Ltd | Professional & scientific | 2021 |
| UK Recycle Limited | Water & waste | 2004 |
| UK Weddings Limited | Professional & scientific | 2021 |
| Ukme Services Ltd | Agriculture & fishing | 2020 |
| Umbrella Ready Limited | Professional & scientific | 2024 |
| Uncommonsense.World Limited | Education | 2025 |