| Woodpecker Property Maintenance Ltd | Construction | 2023 |
| Woodsmith (SW) Limited | Construction | 2013 |
| Wordsworth Construction Limited | Construction | 2018 |
| World Time Solutions Limited | Manufacturing | 2008 |
| Wrighthaus Ltd | Real estate | 2025 |
| Wroxton Estates Limited | Real estate | 2012 |
| WS Project Consulting Limited | Professional & scientific | 2013 |
| WTP Hire Limited | Administrative & support | 2017 |
| Www.Icxi.Com (UK) Limited | Wholesale & retail | 2018 |
| Wycke H Limited | Professional & scientific | 2014 |
| Wycke H1 Limited | Financial services | 2021 |
| Xtreme Graphics Limited | Manufacturing | 2001 |
| Y Cymraes Ltd | Other services | 2022 |
| Yard Vets Limited | Professional & scientific | 2022 |
| Yarinlar Limited | Hospitality | 2023 |
| Yarnton Day Nursery Limited | Education | 2023 |
| YE Olde Dairy Management Limited | Households | 2021 |
| Yearone Management Company Ltd | Professional & scientific | 2018 |
| Yonder Consultants Limited | Professional & scientific | 2024 |
| Yoopa Limited | Education | 2010 |
| Yorfalar Ltd | Hospitality | 2024 |
| Yourchefs Ltd | Manufacturing | 2022 |
| Yuzalab Limited | Information & communication | 2020 |
| Z-Path Limited | Financial services | 2024 |
| Zamolo's Limited | Hospitality | 2022 |
| Zanda Engineering Ltd | Professional & scientific | 2015 |
| ZERO6 Services Ltd | Information & communication | 2021 |
| Zest for Brands Ltd | Professional & scientific | 2025 |
| Ziemelis Motorsport Limited | Education | 2010 |
| Zoni Ltd | Real estate | 2024 |