| Westlands Casting Co Limited | Manufacturing | 1962 |
| Westone Scaffolding Limited | Construction | 2020 |
| Westward Projects Limited | Health & social care | 2010 |
| Westward Training Limited | Education | 2012 |
| Westway Civils Ltd | Construction | 2020 |
| Wexford Facades Limited | Other services | 2021 |
| WGM Consultancy Limited | Professional & scientific | 2019 |
| Wheels With Nuts Ltd | Wholesale & retail | 2023 |
| Whereabts Limited | Information & communication | 2026 |
| Whibleys News Food & Wine Limited | Wholesale & retail | 2012 |
| White Hammond Limited | Professional & scientific | 2014 |
| White Vase Ltd | Health & social care | 2014 |
| Whitehorse Road Ltd | Financial services | 2023 |
| Whites Catering Equipment Ltd. | Hospitality | 2018 |
| Whites Property Management LLP | | 2007 |
| Whitestar Systems Ltd | Information & communication | 2012 |
| Whitsundale E1 Limited | Arts & recreation | 2022 |
| Whitsundale Gloucester Limited | Arts & recreation | 2023 |
| Whitworths Food Group Ltd | Financial services | 2025 |
| Whitworths Holdings Limited | Professional & scientific | 2003 |
| Whitworths Investments Limited | Professional & scientific | 2000 |
| Whitworths Limited | Manufacturing | 2004 |
| Wholesale Shoes Limited | Wholesale & retail | 2025 |
| WHT Finance Ltd | Other services | 2025 |
| Widdowson Consultants Ltd | Administrative & support | 2020 |
| Wight Farm Energy 1 Limited | Administrative & support | 2018 |
| Wight Farm Energy 2 Limited | Administrative & support | 2018 |
| Wight Farm Energy LLP | | 2012 |
| Wiktor 2015 Ltd | Transport & logistics | 2015 |
| Wiktor Ltd | Wholesale & retail | 2014 |
| Wilby Homes Limited | Real estate | 1998 |
| Wilby Tree Biomass Limited | Wholesale & retail | 2016 |
| Wilder Filly Ltd. | Wholesale & retail | 2024 |
| Wildwood & Saws Ltd | Manufacturing | 2020 |
| Willamsco Ltd | Real estate | 2026 |
| William H. Benjamin Limited | Information & communication | 2018 |
| Willmott Transport Limited | Transport & logistics | 2008 |
| Willowvale Care Limited | Health & social care | 2021 |
| Wills Direct Limited | Professional & scientific | 2025 |
| Wills DP Limited | Professional & scientific | 2025 |
| Wilsans Carvery & Steakhouse Limited | Hospitality | 2013 |
| Wiltshire Commercial Cleaning Ltd | Administrative & support | 2024 |
| Win-Dor Limited | Extraterritorial | 1992 |
| Wing World Flavours Limited | Hospitality | 2024 |
| Wings 101 Wellingborough Limited | Hospitality | 2025 |
| Winifred Wharton Trust | Arts & recreation | 1999 |
| Winsigns Limited | Professional & scientific | 2002 |
| Winters Heating Services Limited | Professional & scientific | 2022 |
| Winterwood Kitchens Limited | Manufacturing | 2025 |
| Wipi Limited | Administrative & support | 2013 |
| Wireko Ltd | Manufacturing | 2025 |
| Wishing Well Care Limited | Health & social care | 2016 |
| Wittmann Battenfeld UK Ltd. | Wholesale & retail | 1959 |
| Wizardware Limited | Information & communication | 2024 |
| Wizzaer Ltd | Transport & logistics | 2020 |
| WML Logistics Ltd | Transport & logistics | 2015 |
| Woah Nutrition Ltd | Wholesale & retail | 2020 |
| WOK With U Ltd | Hospitality | 2026 |
| Wold Farm Country Pursuits Ltd | Arts & recreation | 2019 |
| Wold Farm Events Ltd | Arts & recreation | 2024 |
| Wolf-Tech Engineering Limited | Manufacturing | 2014 |
| Wolfpack Property Developments Limited | Construction | 2021 |
| Wollaston Ceramic Solutions Limited | Construction | 2021 |
| Wollaston Consultancy Services Limited | Administrative & support | 2014 |
| Wollaston Spice Ltd | Hospitality | 2026 |
| Wolverton Road 1966 Limited | Extraterritorial | 2014 |
| Womack Construction Limited | Construction | 2024 |
| Woodcock Melting Co. Limited | | 1983 |
| Woods Compliance Solutions Limited | Administrative & support | 2004 |
| Woodview Nursery Limited | Construction | 2014 |
| Woof Marketing Ltd | Professional & scientific | 2023 |
| Woolley Hall Freehold Limited | Households | 2018 |
| Wootton Fields Roofing Limited | Construction | 2007 |
| Word of Life Ministries UK Limited | Other services | 1981 |
| Work Welfare Support Ltd | Health & social care | 2022 |
| Workshop Resource Limited | Wholesale & retail | 2017 |
| Wrapit Packaging Ltd | Administrative & support | 2012 |
| Wren Construction and Conservation Ltd | Construction | 2018 |
| Wristfix Wristbands Ltd | Manufacturing | 2020 |
| Wrobel Houses Ltd | Real estate | 2025 |
| WWO Support Limited | Other services | 2021 |
| X Paradigm Ltd | Wholesale & retail | 2024 |
| X3 Associates Ltd | Professional & scientific | 2015 |
| Xadeworks Ltd | Information & communication | 2025 |
| Xhealth Limited | Health & social care | 2018 |
| Xmaster Transport Ltd | Transport & logistics | 2026 |
| Xpert Utility Services Limited | Energy | 2025 |
| Xtend Building Services Limited | Construction | 2024 |
| XYZ Transport Ltd | Transport & logistics | 2023 |
| Y&B Aesthetics Ltd | Other services | 2021 |
| Yardies Food Ltd | Manufacturing | 2019 |
| Yarmouth Sea School and Charter Limited | Transport & logistics | 2025 |
| Yates Villas Management Services Limited | Households | 1996 |
| Ycottagehouse Ltd | Hospitality | 2025 |
| Yebo Design & Marketing Limited | Professional & scientific | 2013 |
| Yellow Rose Properties Limited | Construction | 2016 |
| Yellow Rowan Ltd | Manufacturing | 2025 |
| Yellow Shop Mini Market Ltd | Wholesale & retail | 2025 |
| Yellow Wolves Ltd | Construction | 2026 |
| Yftodi Ltd | Construction | 2022 |