| Woolwich Specsavers Hearcare Limited | Wholesale & retail | 2026 |
| Wootton Bassett Specsavers Limited | Wholesale & retail | 2022 |
| Worcester Newmedica Limited | Health & social care | 2021 |
| Worcester Park Specsavers Limited | Wholesale & retail | 2016 |
| Worcester Specsavers Hearcare Limited | Wholesale & retail | 2003 |
| Worcester Specsavers Limited | Wholesale & retail | 1999 |
| Worcester Visionplus Limited | Wholesale & retail | 1999 |
| Wordclarke Limited | Professional & scientific | 2008 |
| Work From Home Network (UK) Ltd. | Wholesale & retail | 2018 |
| Workflo Consulting Ltd | Information & communication | 2015 |
| Workington Specsavers Limited | Wholesale & retail | 1994 |
| Workington Visionplus Limited | Wholesale & retail | 1994 |
| Worklyflow Ltd | Information & communication | 2024 |
| Workmode Ltd | Administrative & support | 2020 |
| Worksop Specsavers Limited | Wholesale & retail | 1992 |
| Worksop Visionplus Limited | Wholesale & retail | 1992 |
| Workspan Limited | Transport & logistics | 1987 |
| World at Their Feet Limited | Extraterritorial | 2008 |
| World of Tackle Limited | Wholesale & retail | 2012 |
| World Transfer Services Ltd | Transport & logistics | 2023 |
| Worle Specsavers Limited | Wholesale & retail | 2022 |
| Worthing Specsavers Hearcare Limited | Wholesale & retail | 2007 |
| Worthing Specsavers Limited | Wholesale & retail | 1992 |
| Worthing Visionplus Limited | Wholesale & retail | 1991 |
| WOW a Tour Limited | Administrative & support | 2018 |
| WP Solar Limited | Administrative & support | 2025 |
| WPS Southern Limited | Construction | 2014 |
| Wrap Specialist Ltd | Construction | 2026 |
| Wrexham Specsavers Hearcare Limited | Wholesale & retail | 2017 |
| Wrexham Visionplus Limited | Wholesale & retail | 1991 |
| Wright Choice Catering Limited | Hospitality | 2013 |
| Wright Way Builders Ltd | Construction | 2023 |
| Wtgw Holdings Ltd | Administrative & support | 2020 |
| Wumly Ltd | Wholesale & retail | 2024 |
| Wylde Waters Limited | Construction | 2024 |
| Wymondham Specsavers Limited | Wholesale & retail | 2018 |
| Wyndham Gregory Ltd | Professional & scientific | 2019 |
| Wärtsilä Voyage Holding Limited | Financial services | 2016 |
| Wärtsilä Voyage UK Limited | Manufacturing | 2002 |
| X-Am Training Ltd | Education | 2023 |
| X-On-X Ltd | Professional & scientific | 2025 |
| X-Tend With Style Ltd | Wholesale & retail | 2011 |
| X100 Education Ltd | Professional & scientific | 2025 |
| Xebra Accounting IHC Limited | Professional & scientific | 2018 |
| Xebra Accounting Limited | Professional & scientific | 2013 |
| Xinke Ltd | Administrative & support | 2014 |
| XJC Jets Limited | Administrative & support | 2016 |
| Xogo Sports Limited | Wholesale & retail | 2016 |
| XPA Consulting Limited | Professional & scientific | 2012 |
| Xpol Logistics Ltd | Transport & logistics | 2023 |
| Xtremity Limited | Wholesale & retail | 2021 |
| Xtremity Sports Ltd | Education | 2016 |
| Xvconsultant Ltd | Professional & scientific | 2018 |
| Xvstripes Limited | Other services | 2019 |
| Xwren Associates Ltd | Information & communication | 2011 |
| XYZ Newco Limited | Financial services | 2026 |
| Y&H Fareham Ltd | Other services | 2025 |
| Yacht Composites Ltd | Manufacturing | 2025 |
| Yachtequip Ltd | Other services | 2016 |
| Yaesu UK Ltd. | Manufacturing | 1994 |
| Yankeys Global Relocation Ltd | Hospitality | 2024 |
| Yardley Specsavers Limited | Wholesale & retail | 2011 |
| Yates Corp Ltd | Financial services | 2024 |
| Yates.Em Ltd | Construction | 2026 |
| YCF Motorcycles UK Ltd | Wholesale & retail | 2013 |
| Yegane Group Limited | Financial services | 2023 |
| Yellow Engineering Ltd | Professional & scientific | 2018 |
| Yellowwood Management Services Limited | Other services | 2021 |
| Yellowwood Residential Limited | Other services | 2021 |
| Yeovil Specsavers Hearcare Limited | Wholesale & retail | 2005 |
| Yeovil Specsavers Limited | Wholesale & retail | 1991 |
| Yeovil Visionplus Limited | Wholesale & retail | 2002 |
| YES Technology Solutions Ltd | Information & communication | 2007 |
| Yesterday Studio Ltd | Professional & scientific | 2025 |
| YI Dian Dian London Ltd | Wholesale & retail | 2026 |
| YLC Consulting Ltd | Information & communication | 2024 |
| YMF Developments Limited | Construction | 2024 |
| Ynez Ltd | Health & social care | 2017 |
| Ynrd Ltd | Health & social care | 2023 |
| Yocker Competitions Ltd | Arts & recreation | 2026 |
| Yoga With Betsy Ltd | Education | 2024 |
| Yoglates Limited | Wholesale & retail | 2014 |
| Yoki Engineering Limited | Administrative & support | 2011 |
| York 1 Domiciliary Specsavers Limited | Wholesale & retail | 2017 |
| York Domi Audiology Specsavers Limited | Wholesale & retail | 2023 |
| York Specsavers Hearcare Limited | Wholesale & retail | 2005 |
| York Specsavers Limited | Wholesale & retail | 1988 |
| York Transport and Waste Solutions Ltd | Water & waste | 2025 |
| York Visionplus Limited | Wholesale & retail | 1999 |
| Younas Bros Ltd | Real estate | 2022 |
| Youngs Creative Limited | Professional & scientific | 2024 |
| Youngsie Bullion Ltd | Wholesale & retail | 2026 |
| Youp Consulting Ltd | Professional & scientific | 2023 |
| Your Clean Move Ltd | Administrative & support | 2021 |
| Your Club Stash Ltd | Wholesale & retail | 2021 |
| Your Digital Support Hub Ltd | Education | 2022 |
| Your Doctor Film and Media Limited | Health & social care | 2015 |
| Your Financial Toolbox Limited | Financial services | 2021 |
| Your General Company Limited | Other services | 2017 |
| Your Local Building Company Limited | Construction | 2017 |