| Westline Publishing Limited | Information & communication | 2001 |
| Westover Developments Ltd | Construction | 2017 |
| Westwiltsfencing Ltd | Construction | 2026 |
| Weymouth House Management Company Limited | Households | 1989 |
| Whatley International Ltd | Transport & logistics | 2025 |
| Whicker Consulting Limited | Professional & scientific | 2018 |
| White Horse Marquees Limited | Administrative & support | 1978 |
| White Sheet Farmers Limited | Agriculture & fishing | 1978 |
| Wifi Signal Craft Ltd | Information & communication | 2025 |
| Wilds & Co (Stockbridge) Limited | Hospitality | 2022 |
| Wilds Holdings Limited | Financial services | 2022 |
| Will Puddy Professional Sport Limited | Extraterritorial | 2011 |
| William Neville Associates Limited | Professional & scientific | 2015 |
| Willow Motors Ltd | Manufacturing | 2021 |
| Willow Property Developments (SW) Ltd | Construction | 2017 |
| Wilson & Kennard Limited | Real estate | 1929 |
| Wiltshire Grappling Academy and Combat Centre Ltd | Arts & recreation | 2022 |
| Wiltshire Outdoor Learning Team C.I.C. | Education | 2014 |
| Wiltshire Pest Services Limited | Administrative & support | 2018 |
| Wiltshire RAW Dog Food Limited | Wholesale & retail | 2019 |
| Winchester Renewables Limited | Energy | 2022 |
| Wingfield Brothers Limited | Professional & scientific | 2012 |
| Woodlands (Mere) Limited | Real estate | 2001 |
| Wunder School Ltd | Education | 2023 |
| Wylye Coyotes Afterschool Club C.I.C | Health & social care | 2009 |
| Wylye Vale Limited | Real estate | 2021 |
| Wylye Valley Crafts Limited | Professional & scientific | 2017 |
| Wylye Valley Designs Limited | Professional & scientific | 2017 |
| Wylye Valley Limited | Agriculture & fishing | 2008 |
| Wylye Valley Padel Limited | Arts & recreation | 2026 |
| Yard Court Residents Limited | Households | 2015 |
| YES YOU CAN Wiltshire Community Interest Company | Health & social care | 2014 |
| Yeti Electrical Solutions Ltd | Construction | 2022 |
| Yeti Games Ltd | Manufacturing | 2011 |
| YEW Tree Fieldsports & Game Ltd | Arts & recreation | 2013 |
| Yunik Delivery Ltd | Transport & logistics | 2023 |
| Zeals Afterschools Club CIC | Health & social care | 2022 |
| Zeals Consulting Limited | Professional & scientific | 2023 |
| Zeals Hand Car Wash Limited | Administrative & support | 2023 |
| Zootopia Ltd | Hospitality | 2009 |
| Zuperzonic Limited | Hospitality | 2019 |