| THE Lettings People Ltd | Real estate | 1999 |
| THE Logo House Ltd | Manufacturing | 2025 |
| THE Magic Video Company Limited | Information & communication | 2011 |
| THE Nutrition Consultant Ltd. | Professional & scientific | 2016 |
| THE O & E Consultancy Ltd | Construction | 2024 |
| THE Office of the House of Cooper LLP | | 2026 |
| THE Old Brewery (Furnex Pelham) Management Ltd | Households | 1999 |
| THE Phoenix Project Online Learning Limited | Education | 2024 |
| THE Sustainabilitycompany Ltd | Professional & scientific | 2020 |
| THE Wellness Business LAB Ltd | Education | 2024 |
| THE Willow Tree OUT of School Club Ltd | Health & social care | 2025 |
| THE Wills & Trusts Practice Ltd | Information & communication | 2009 |
| THE Wrinkle Fairy Ltd | Other services | 2021 |
| THI Holdings Ltd | Financial services | 2021 |
| Tindy Ltd | Transport & logistics | 2026 |
| Tiny Ties Ltd | Health & social care | 2025 |
| Tiny Town Adventure Mainstreet Ltd | Health & social care | 2024 |
| Tommy Willis Ltd | Administrative & support | 2025 |
| Toucan Advisory Ltd | Administrative & support | 2023 |
| Tournier Consultants Ltd | Professional & scientific | 2019 |
| Tracey Phillips Accountancy Limited | Professional & scientific | 2012 |
| Trade Investment (U.K.) Limited | Real estate | 1985 |
| Trevor Prior Agricultural Services Limited | Agriculture & fishing | 2013 |
| Triple Eight Race Engineering Limited | Manufacturing | 1996 |
| Trotters Electrical Ltd | Construction | 2026 |
| Trucold Limited | Real estate | 2025 |
| Truegame Limited Partnership | | 2021 |
| Truffle Tree Limited | Administrative & support | 1981 |
| Two Acres Management Company Limited | Real estate | 2010 |
| Tylers Close (Buntingford) Management Company Ltd | Administrative & support | 2021 |
| Ubob Ltd | Information & communication | 2020 |
| UK Services AC LLP | | 2026 |
| Unify VSN Limited | Manufacturing | 2021 |
| Unique Techniques Ltd | Health & social care | 2024 |
| Urisk Limited | Water & waste | 2011 |
| WAI Financial Consultants Limited | Professional & scientific | 2003 |
| Walker's Garage (Buntingford) Limited | Wholesale & retail | 2007 |
| Warranty Protect Limited | Financial services | 2020 |
| Warrens Emerald Biogas Ltd | Agriculture & fishing | 2009 |
| Warrens Group Limited | Water & waste | 1986 |
| Wasim Khan Ltd | Health & social care | 2016 |
| WE ARE Digital Vision Ltd | Professional & scientific | 2012 |
| WHEEL2REEL Ltd | Wholesale & retail | 2019 |
| Whitchurch AD Limited | Energy | 2015 |
| White Cedar Ltd | Real estate | 2026 |
| White Room Music Limited | Information & communication | 2021 |
| Wholehearted Home Care Ltd | Health & social care | 2022 |
| William Court Freehold Limited | Households | 2011 |
| Windmill Lodge Ltd | Health & social care | 2021 |
| Wingfield Estates Ltd | Other services | 2019 |
| Wired Solutions Limited | Construction | 2021 |
| WM Fire Safety Ltd | Public administration | 2023 |
| WMB Design Solutions Ltd | Professional & scientific | 2025 |
| Wollerau Pharma Suisse LP | | 2020 |
| Woodlee Technical Services Ltd | Administrative & support | 2016 |
| Woodside Landscaping Ltd | Administrative & support | 2024 |
| Workwell Risk Management Ltd | Financial services | 2025 |
| WR Shambrook Services Ltd | Construction | 2013 |
| WRR Builders Limited | Construction | 2025 |
| WT Garden Services Ltd | Administrative & support | 2025 |
| Wyddial Asset Managers Limited | Real estate | 2025 |
| Wyddial GP Investor Limited | Real estate | 2025 |
| Wyddial Hall Farms Ltd | Agriculture & fishing | 2020 |
| Wyddial Investment Group Limited | Administrative & support | 2025 |
| Wyddial Partner Limited | Administrative & support | 2025 |
| WYN Building Services Ltd | Construction | 2023 |
| Yodes Limited | Professional & scientific | 2025 |
| Zampa Road Consulting Limited | Professional & scientific | 2026 |
| ZEG Zero Emission Group Limited | Administrative & support | 2020 |
| Zero Emission Group Limited | Administrative & support | 2020 |
| ZJ Consultancy Ltd | Transport & logistics | 2024 |