| Tourmaline Energy Limited | Professional & scientific | 2018 |
| Towbar Services Limited | Wholesale & retail | 1999 |
| Towerclass Limited | Administrative & support | 1987 |
| Tpsl Management Services Limited | Professional & scientific | 2003 |
| Trade Services Andover Ltd | Construction | 2025 |
| Transea Limited | Professional & scientific | 2013 |
| Tregarthen's (ST Mary's) Limited | Hospitality | 2015 |
| Tregarthen's Hotel Limited | Hospitality | 2019 |
| Treloar Tanks LLP | | 2015 |
| Tres Jolie Consultancy Limited | Professional & scientific | 2017 |
| Trickledown Stables Management Company Limited | Households | 2020 |
| Tricky Wolf Ltd | Professional & scientific | 2018 |
| Trinity Property Partners Limited | Real estate | 2026 |
| Trojan Management Group Limited | Real estate | 2021 |
| TSC Environmental Ltd | Professional & scientific | 2019 |
| Tucker Building and Landscaping Limited | Construction | 2025 |
| Tunnel Tech Limited | Agriculture & fishing | 1984 |
| TW Glazing and Window Repairs Limited | Construction | 2014 |
| TXL Limited | Construction | 2014 |
| Type One Investments Limited | Real estate | 2019 |
| Uberbinder Limited | Professional & scientific | 2021 |
| UL Marketing Solutions Ltd | Hospitality | 2019 |
| Umoya Mandla Limited | Manufacturing | 2011 |
| Unicheq Group Limited | Professional & scientific | 2008 |
| Unicheq Holdings Limited | Administrative & support | 1969 |
| Upper Eldon Water Company Limited | Water & waste | 2025 |
| VAL Lewington Medical Limited | Health & social care | 2015 |
| Value Added Consultancy Ltd | Professional & scientific | 2011 |
| Vectis Accountants Ltd | Professional & scientific | 2003 |
| Vintner Group Limited | Administrative & support | 2026 |
| VIP Car Club Ltd | Real estate | 2016 |
| Vital Future Cleaners Ltd | Households | 2023 |
| Wadehold Limited | Professional & scientific | 1999 |
| Walcote (Priors Orchard) Limited | Construction | 2024 |
| Walcote Homes Limited | Financial services | 2024 |
| Walcote Homes Project LR26 Limited | Construction | 2026 |
| Walcote Homes Project WC26 Limited | Construction | 2026 |
| Walkaboutvet Limited | Professional & scientific | 2013 |
| Wallop Design Studio Limited | Professional & scientific | 2001 |
| Wallop Energy Limited | Administrative & support | 2020 |
| Wallop Storage Ltd | Transport & logistics | 2024 |
| Wallops PVT Hire Ltd | Transport & logistics | 2024 |
| Warrah Resources Limited | Professional & scientific | 2022 |
| Wellhound Ltd | Manufacturing | 2025 |
| Wessex Mews Management Co Limited | Households | 1994 |
| Westprime Limited | Construction | 2010 |
| Whisky Sierra Limited | Professional & scientific | 2014 |
| Whole Bunch Advisory Ltd | Professional & scientific | 2021 |
| Wild Earth Ecology Ltd | Professional & scientific | 2026 |
| Wilibby Ltd | Professional & scientific | 2022 |
| Winchester Heritage Developments Ltd | Construction | 2026 |
| Winchester Road Capital Limited | Professional & scientific | 2021 |
| Witham River Capital Limited | Professional & scientific | 2025 |
| Wolversdene Road Andover Property Management Company Ltd | Administrative & support | 2015 |
| Wolverson Limited | Professional & scientific | 2013 |
| Woodslee Landscapes Ltd | Administrative & support | 2024 |
| WP Concepts Ltd | Construction | 2023 |
| Wright Younger Partnership Limited | Administrative & support | 2024 |
| Yacht Creations UK Ltd | Manufacturing | 2009 |
| Yellow Car Driver Training Ltd | Education | 2025 |
| Younger Marketing Management Limited | Wholesale & retail | 2000 |
| Yourcars Andover Ltd | Transport & logistics | 2023 |
| Zmarine Consultancy Services Ltd | Professional & scientific | 2024 |