| THE Retreat Rooms - Berkhamsted Limited | Extraterritorial | 2022 |
| THE REX Cinema Berkhamsted Limited | Arts & recreation | 2002 |
| THE River Gipping Trust Limited | Arts & recreation | 2007 |
| THE Shakespeare Circus Ltd | Education | 2023 |
| THE Shenstone Management Company Limited | Households | 1997 |
| THE Shipyard Venture Studio Ltd | Information & communication | 2026 |
| THE Silver Fern Group Ltd | Professional & scientific | 2013 |
| THE Stamford Southport Ltd | Hospitality | 2019 |
| THE Stationery Supplies Co. Limited | Administrative & support | 2001 |
| THE Strategy Place Ltd | Professional & scientific | 2014 |
| THE Style Desk Ltd | Manufacturing | 2021 |
| THE Swan Youth Project Limited | Health & social care | 1994 |
| THE Teachers' Health Coach Ltd | Health & social care | 2023 |
| THE TIN Cans Awards Limited | Other services | 2024 |
| THE Upholsterers Studio Limited | Manufacturing | 1996 |
| THE Victoria Bushey Ltd | Hospitality | 2021 |
| THE Village Nursery Bellingdon Ltd | Education | 2014 |
| THE Warehouse Pizza Property Company Limited | Real estate | 2021 |
| THE Wellness Collection CIC | Other services | 2025 |
| THE Wellness Hub Recovery Ltd | Arts & recreation | 2026 |
| THE Western Chamber of Control (Three) Ltd | Professional & scientific | 2025 |
| THE Wilder Collective Ltd | Arts & recreation | 2024 |
| THE Wings Room Ltd | Hospitality | 2026 |
| Thegrafter Ltd | Professional & scientific | 2022 |
| This IS Fractional Ltd | Professional & scientific | 2025 |
| This Property Life Limited | Information & communication | 2025 |
| Thomas Communications Limited | Professional & scientific | 2019 |
| Thomas LEE Recruitment Limited | Administrative & support | 2016 |
| Thorn Plant Hire Limited | Administrative & support | 1988 |
| Three Chimneys Associates Limited | Professional & scientific | 2023 |
| Three Counties Fencing & Landscaping Ltd | Administrative & support | 2026 |
| Three Sisters Holidays Limited | Hospitality | 2021 |
| Thunderbolt Television Limited | Information & communication | 2007 |
| Thurso Enterprises Limited | Administrative & support | 2009 |
| Tibbles & Sons Gardening & Home Maintenance Limited | Construction | 2024 |
| Tidal Rush Tees Limited | Wholesale & retail | 2026 |
| Tide Immigration Limited | Other services | 2017 |
| Tidy INK Design Ltd | Professional & scientific | 2020 |
| Tidy TV Limited | Information & communication | 2021 |
| Tiger Coast Ltd | Hospitality | 2025 |
| Tignes Direct Ltd | Administrative & support | 2011 |
| Tinkers END Developments Ltd | Real estate | 2023 |
| Tinpot DOT UK Ltd | Information & communication | 2023 |
| Tiny VFX Limited | Information & communication | 2016 |
| TIP Top Windows Ltd | Construction | 2025 |
| TJB Building Solutions Limited | Construction | 2017 |
| TJG Drinks Limited | Wholesale & retail | 2021 |
| TL E-Accounting Ltd | Information & communication | 2021 |
| TMB Scaffolding Ltd | Construction | 2025 |
| TMC Real Estate Limited | Households | 2025 |
| TO Resourcing Limited | Administrative & support | 2015 |
| Today-Trans Limited | Transport & logistics | 2023 |
| TOI Group Ltd | Wholesale & retail | 2025 |
| Torettosuk Limited | Hospitality | 2026 |
| TPE Property Ltd | Real estate | 2025 |
| TRADFI2DEFI Ltd | Financial services | 2025 |
| Tranquil Sounds Limited | Health & social care | 2025 |
| Trans Mario Ltd | Transport & logistics | 2026 |
| Transcomm Recruitment Ltd | Administrative & support | 2019 |
| Transformed Spaces Ltd | Wholesale & retail | 2005 |
| Traveltime World Limited | Administrative & support | 1994 |
| Tread Floor Ltd | Construction | 2014 |
| Tread Holdings Ltd | Financial services | 2025 |
| Tricky Tree Limited | Professional & scientific | 2013 |
| Tropical Travel Ltd | Administrative & support | 2015 |
| Trotman Limited | Professional & scientific | 2015 |
| TRS (Worldwide) Limited | Manufacturing | 2011 |
| TSM Plumbing Ltd | Construction | 2013 |
| Tula Chiropractic Ltd | Health & social care | 2023 |
| Tutton Trading Ltd | Wholesale & retail | 2026 |
| Tutu & Co. Ltd | Construction | 2017 |
| Two FAT Gerbils Ltd | Professional & scientific | 2022 |
| TWP Bespoke Limited | Construction | 2021 |
| TY Interiors Ltd. | Wholesale & retail | 2022 |
| Typt Ltd | Education | 2021 |
| U.K. Asbestos Plant & Machinery Limited | | 1983 |
| UK Static Holidays Ltd | Hospitality | 2017 |
| Umbrella Music Limited | Professional & scientific | 1999 |
| Underwood Automotive Services Limited | Wholesale & retail | 2016 |
| Unifit Games Limited | Arts & recreation | 2023 |
| Universal Electrix Limited | Wholesale & retail | 2002 |
| Universal Food & Wine Store Ltd | Wholesale & retail | 2022 |
| Upstream Risk Management Limited | Administrative & support | 2018 |
| Urban Arborcare Ltd | Other services | 2017 |
| Urban House (Berkhamsted) Ltd | Real estate | 2024 |
| USA Nails (Berkhamsted) Limited | Other services | 2007 |
| UX Digital Systems Limited | Information & communication | 2016 |
| Uz-Air Ltd | Professional & scientific | 2020 |
| V Edit Life Ltd | Other services | 2023 |
| V Read Consulting Ltd | Professional & scientific | 2024 |
| Vadercom Ltd | Professional & scientific | 2011 |
| Valora Solutions Limited | Information & communication | 2026 |
| Value Solutions Consulting Limited | Extraterritorial | 2016 |
| VC Energy Limited | Real estate | 2013 |
| Vecta Creative Limited | Professional & scientific | 2016 |
| Vector Asset Finance Limited | Financial services | 2018 |
| Vector Business Finance Limited | Financial services | 2015 |
| Vector Capital Limited | Financial services | 2019 |
| Vector Holdings Limited | Financial services | 1978 |
| Vector London Limited | Financial services | 2017 |