| Whax Holdings Ltd | Manufacturing | 2019 |
| Which Stairlift Limited | Wholesale & retail | 2009 |
| Whishaw Message Limited | Professional & scientific | 2022 |
| Whispering Giraffe Productions Ltd | Information & communication | 2018 |
| Whistlejacket Equine Surgery Ltd | Professional & scientific | 2011 |
| White Coat Captioning UK Ltd | Information & communication | 2017 |
| White Court Weymouth Limited | Households | 1993 |
| White Horse Camping Ltd | Hospitality | 2024 |
| White M Limited | Wholesale & retail | 2014 |
| White Ocean Racing Ltd | Wholesale & retail | 2005 |
| White Rose Court (Management) Limited | Households | 1977 |
| Whitefriars Properties Limited | Households | 2003 |
| Whites PHS Limited | Construction | 2011 |
| Whiteside Apartments Management Company Limited | Households | 2014 |
| Whitestem Ltd | Agriculture & fishing | 2026 |
| Whitstone's (Norton Hill) Limited | Hospitality | 2012 |
| Whitstone's Traditional Fish & Chips (Westfield) Limited | Hospitality | 2009 |
| Whitstone's Traditional Fish and Chips Limited | Hospitality | 2004 |
| Whyteland Limited | Construction | 2013 |
| Wicks Property Services Ltd | Construction | 2022 |
| Wifi Shop Limited | Information & communication | 2014 |
| Wigglets CIC | Other services | 2019 |
| Wiktor Holdings Limited | Hospitality | 2023 |
| Wilber & Co Limited | Construction | 2008 |
| Wild River Media Ltd | Professional & scientific | 2023 |
| Wild Suite Limited | Information & communication | 2023 |
| Wildbrook Investments (Calne) Limited | Real estate | 2004 |
| Wildbrook Investments (Thornbury) Limited | Real estate | 1996 |
| Wildbrook Investments Limited | Real estate | 1996 |
| Wildbrook Properties Limited | Real estate | 1996 |
| Wildfire Training and Consultancy Ltd | Other services | 2022 |
| Wildforce Ltd | Professional & scientific | 2022 |
| Wildish & Co Limited | Professional & scientific | 2011 |
| Wilkinson Properties Limited | Administrative & support | 2020 |
| Willes Jewellers Limited | Wholesale & retail | 2012 |
| William Holland Limited | Wholesale & retail | 2003 |
| Williams Electrical (Dorset) Ltd | Construction | 2021 |
| Willow and Thyme Ltd | Wholesale & retail | 2020 |
| Willowborne Garden Residents Association Limited | Households | 1995 |
| Willowbrook Management Limited | Households | 1987 |
| Wilson Tominey Group Limited | Real estate | 2012 |
| Wilton Fallen Stock Limited | Agriculture & fishing | 2023 |
| Wilton Hunt Limited | Agriculture & fishing | 2012 |
| Wimborne AF Ltd | Arts & recreation | 2026 |
| Wimborne Dental Laboratory Ltd. | Health & social care | 2002 |
| Wimborne Financial Services Limited | Financial services | 2007 |
| Windmills Management Company (Dorset) Limited | Households | 2016 |
| Windowman Dorchester Limited | Construction | 2020 |
| Winterbourne Abbas Tyre and Auto Services Limited | Manufacturing | 2017 |
| Wire and Wood Limited | Wholesale & retail | 2022 |
| Wise OWL Toys (Dorchester) Limited | Wholesale & retail | 2002 |
| Wisscom Aerospace Limited | Information & communication | 2014 |
| Withypitts Limited Partnership | | 1989 |
| WJR Enterprises Limited | Hospitality | 2019 |
| Woldhurst Limited | Hospitality | 1970 |
| Women in Tech Dorset CIC | Other services | 2023 |
| Woodacre (Broadmayne) Management Limited | Households | 2007 |
| Woodford Construction Management Limited | Professional & scientific | 2015 |
| Woodholt Plumbing, Heating & Electrical Limited | Construction | 2016 |
| Woodlanders Management Ltd | Households | 2001 |
| Woodlands Gate Poundbury Management Company Ltd | Households | 2006 |
| Woodlark Farms Ltd | Agriculture & fishing | 2017 |
| Woods (Dorchester) Limited | Wholesale & retail | 1942 |
| Woods Industrial Limited | Construction | 2022 |
| Woodsford Farms Limited | Agriculture & fishing | 1951 |
| Woodsford Limited | Extraterritorial | 1964 |
| Woodstock Estates Limited | Construction | 1931 |
| Woogiebigpants Ltd | Wholesale & retail | 2019 |
| Wool Chippy Company Limited | Hospitality | 2022 |
| Words: Paul Machin Limited | Information & communication | 2006 |
| Wordsworth House Limited | Health & social care | 2003 |
| World Life Global Ltd | Hospitality | 2024 |
| Worldwide Butterflies Limited | Administrative & support | 2013 |
| Worldwide Waste Wise Limited | Education | 2014 |
| Wrackleford Farms Limited | Agriculture & fishing | 1961 |
| Wraxall Yard CIC | Hospitality | 2019 |
| Wright Pugson Chain Limited | Manufacturing | 2000 |
| WS Fitting Limited | Construction | 2014 |
| Wykes Gate Bridport RTM Company Limited | Households | 2017 |
| Wykeside Technologies Limited | Information & communication | 2017 |
| Wyvern Properties Management Company Limited | Professional & scientific | 2017 |
| Wyvern-Marlborough Limited | Professional & scientific | 1959 |
| Wzard Innovation Ltd | Information & communication | 2017 |
| Xanderly Limited | Real estate | 2021 |
| XEMPLAR3S Ltd | Professional & scientific | 2018 |
| Xicoia Ltd | Information & communication | 2025 |
| XO Dorchester Limited | Hospitality | 2025 |
| Y.C's Dorchester Limited | Hospitality | 2015 |
| Yandere Pocket Dimension Ltd | Wholesale & retail | 2026 |
| Yavin Ltd | Information & communication | 2025 |
| Yeabridge Court Management Company Limited | Households | 2021 |
| Yeovil Fabrication Limited | Construction | 1988 |
| Your View Technical Services Ltd | Construction | 2018 |
| Youth Cancer Trust (UK) Limited | Health & social care | 1997 |
| Z7 Limited | Professional & scientific | 2006 |
| Zabeorca Consultancy Ltd | Health & social care | 2016 |
| Zach Watts Master Thatcher Limited | Construction | 2015 |
| Zaine Trading Limited | Professional & scientific | 2004 |
| Zero Bars Production Limited | Manufacturing | 2025 |
| Zipzappity Limited | Administrative & support | 2011 |