| Wildberry Wood Outdoor Learning Limited | Education | 2018 |
| Wildlifeline | Professional & scientific | 1999 |
| Williams Fascia, Soffits & Guttering Ltd | Construction | 2022 |
| Williamson Carson and Company Limited | Financial services | 1976 |
| Wilson Contracting Ltd | Construction | 2019 |
| WIN Transport UK Limited | Transport & logistics | 2021 |
| Wincheap Service Ltd | Wholesale & retail | 2024 |
| Wind Sail Power Systems Ltd | Energy | 2025 |
| Wind Work X Ltd | Administrative & support | 2022 |
| Window Technical Services Ltd | Construction | 2013 |
| Wine Cellar (Brighton) Limited | Wholesale & retail | 2021 |
| Wing Entertainment Ltd | Arts & recreation | 2015 |
| Winning Edge Consultancy Limited | Professional & scientific | 2015 |
| Winstanley Admin Limited | Health & social care | 2026 |
| Winterharbour Ltd | Arts & recreation | 2025 |
| WIP Fireplaces Ltd | Construction | 2026 |
| Wisdom for Women International C.I.C. | Education | 2014 |
| Wise Call Property Ltd | Real estate | 2024 |
| Wise Deal Furniture Ltd | Manufacturing | 2014 |
| Wise Housing Investments Ltd | Real estate | 2026 |
| Wise Waste Management Services Ltd | Water & waste | 2025 |
| WJ Consulting Services Ltd | Information & communication | 2019 |
| Wmba & Leba (Holdings) Limited | Administrative & support | 2011 |
| WOK N Rock Limited | Real estate | 2011 |
| Wolveshill Consulting Ltd. | Wholesale & retail | 2017 |
| Women for Africa (W4A) Limited | Other services | 2011 |
| Women Foundation Ministries-Uk Limited | Administrative & support | 2024 |
| Women Warriors UK CIC | Education | 2026 |
| Women's Health - Carewell Ltd | Health & social care | 2020 |
| Wood Whisperers Workshop Limited | Other services | 2025 |
| Woodbury Court Mackenzie Road Management Limited | Households | 2004 |
| Woodgate Electrical Solutions Limited | Construction | 2011 |
| Woodhill Electrical Ltd | Construction | 2023 |
| Woodlands Court (Bromley) Limited | Households | 1999 |
| Woodmancote Vineyard Limited | Manufacturing | 2026 |
| Woofers &Co Limited | Administrative & support | 2022 |
| WOR Consultancy Limited | Administrative & support | 2008 |
| Worcester Recycling Croydon Ltd | Water & waste | 2021 |
| Work-Room Bristol Limited | Construction | 2021 |
| World's END Technology Ltd | Information & communication | 2015 |
| Worshippers Club Limited | Information & communication | 2021 |
| Worthing Retail Limited Liability Partnership | | 2005 |
| WP Digital Limited | Manufacturing | 1998 |
| WPW Fire Alarm Installations Ltd | Construction | 2025 |
| Wray Mill Park Management Company Limited | Households | 1989 |
| Wraysbury Estates Limited | Financial services | 1968 |
| Wright Sports Solutions Limited | Arts & recreation | 2019 |
| Write My CV Ltd | Information & communication | 2023 |
| Writepush Limited | Information & communication | 2014 |
| WTS Facades Ltd | Construction | 2020 |
| Wurl Ltd | Professional & scientific | 2025 |
| WWC Security Ltd | Construction | 2011 |
| Wyvern Close Management Co Ltd | Households | 2005 |
| X-Star Management Services Limited | Professional & scientific | 2014 |
| Xela Trading Ltd | Wholesale & retail | 2025 |
| XGO Holdings Limited | Transport & logistics | 2018 |
| XGO Trading (UK) Ltd | Wholesale & retail | 2018 |
| XIN Market Ltd | Wholesale & retail | 2024 |
| Xiotex Studios Ltd | Manufacturing | 2007 |
| XP Facilities Limited | Professional & scientific | 2011 |
| XR AK Limited | Real estate | 2025 |
| Xsic Limited | Wholesale & retail | 2025 |
| Y.A.D Development Ltd | Real estate | 2021 |
| Y.A.D Studio Ltd | Professional & scientific | 2013 |
| Yang Investment Limited | Professional & scientific | 2020 |
| Yarbyte Ltd | Information & communication | 2021 |
| Yard Flavas Ltd | Hospitality | 2024 |
| Yasine Ltd | Real estate | 2024 |
| Yd-Tinystars Ltd | Wholesale & retail | 2026 |
| Yearley Creatives Ltd | Arts & recreation | 2025 |
| Yebra Floor Finishing Limited | Other services | 2017 |
| Yebra French Polishing Ltd | Construction | 2007 |
| Yellowconnection Ltd | Professional & scientific | 2019 |
| Yeso Limited | Construction | 2021 |
| YGD Health Limited | Professional & scientific | 2022 |
| Yield Property Investment Ltd | Real estate | 2019 |
| Yijia Grocery Ltd | Wholesale & retail | 2022 |
| Yildiz Anatolian Food Ltd | Hospitality | 2021 |
| YJC Ltd | Hospitality | 2022 |
| YKH Property Limited | Real estate | 2017 |
| YNF529 Limited | Information & communication | 2017 |
| Yoga PVT Ltd | Real estate | 2025 |
| Yormex Healthcare Ltd | Administrative & support | 2017 |
| YOU Control Limited | Construction | 2013 |
| Younty Ltd | Information & communication | 2013 |
| Your Creative Vision Limited | Professional & scientific | 2019 |
| Your DEV Co Ltd | Construction | 2023 |
| Your Heat Ltd | Other services | 2014 |
| Your Manor Construction Limited | Construction | 2025 |
| Your Manor Ltd | Real estate | 2024 |
| Your Real Home Ltd | Real estate | 2025 |
| Your Team Protect Ltd | Wholesale & retail | 2024 |
| YQI Ltd. | Wholesale & retail | 2018 |
| YQI Services Ltd | Other services | 2019 |
| Yummy Yard Ltd | Hospitality | 2026 |
| Yuniya CIC | Education | 2023 |
| YYL Properties Ltd | Real estate | 2020 |
| Z G Environmental Services Limited | Administrative & support | 2024 |
| Z&S Global Enterprise Ltd | Wholesale & retail | 2024 |
| ZA Equity Ltd | Real estate | 2022 |