| Your Local PUB and Leisure Limited | Hospitality | 2017 |
| Your Mortgage People Limited | Financial services | 2013 |
| Your Pet Pals Ltd | Wholesale & retail | 2025 |
| Your Property Manager Ltd | Administrative & support | 2025 |
| Your Retail Shop Limited | Wholesale & retail | 2017 |
| Youraccountants.Online Ltd | Professional & scientific | 2015 |
| YS2 Consulting Limited | Information & communication | 2017 |
| Yuntea Limited | Manufacturing | 2025 |
| Yvette Pickard Ltd | Professional & scientific | 2020 |
| YY Automation Ltd | Professional & scientific | 2012 |
| Z5 Internet Ltd | Information & communication | 2004 |
| Zafferano Concessions Limited | Hospitality | 2011 |
| Zambezi Fest Ltd | Arts & recreation | 2026 |
| Zananet Limited | Information & communication | 2012 |
| Zannogen Ltd | Professional & scientific | 2022 |
| Zantie Limited | Professional & scientific | 2017 |
| ZAP Estates Ltd | Real estate | 2019 |
| Zard Cardz Ltd | Wholesale & retail | 2025 |
| ZAZ Corporation Ltd | Hospitality | 2025 |
| ZCS Limited | Information & communication | 1998 |
| Zebra Tail Lifts Ltd | Manufacturing | 2025 |
| Zekoda Ltd | Information & communication | 2025 |
| ZEN Analytics Ltd | Information & communication | 2024 |
| Zenith Finance Broker Ltd | Financial services | 2025 |
| Zentive Cable Limited | Information & communication | 2012 |
| Zentive Group Holdings Limited | Financial services | 2020 |
| Zentive Limited | Information & communication | 2004 |
| Zentive Skill Limited | Information & communication | 2005 |
| Zentive Systems Limited | Information & communication | 2011 |
| Zentive Time Systems Limited | Information & communication | 2010 |
| Zerda Ltd | Other services | 2024 |
| Zest at Lime Square Limited | Hospitality | 2012 |
| Zestdeck Limited | Information & communication | 2022 |
| ZGEE14 Limited | Professional & scientific | 1952 |
| ZIP Competitions Ltd | Wholesale & retail | 2025 |
| Ziri Holding Ltd | Financial services | 2025 |
| Zoat Ltd | Real estate | 2022 |
| Zocos Consulting Ltd | Professional & scientific | 2024 |
| ZOE Lodrick Ltd | Health & social care | 2010 |
| Zombie Music Limited | Information & communication | 2017 |
| Zoom Broadband Limited | Information & communication | 2020 |
| Zoom Fibre Limited | Information & communication | 2020 |
| Zoom Hairdressing Ltd | Real estate | 2002 |
| Zoom to LET Limited | Real estate | 2006 |
| Zoved Limited | Real estate | 2025 |
| Zuluzy Limited | Extraterritorial | 2023 |
| Zurich Building Control Services Limited | Administrative & support | 2004 |
| Zurich Global Corporate UK Limited | Administrative & support | 1996 |
| Zurich GSH Limited | Financial services | 1969 |
| Zurich Holdings (UK) Limited | Financial services | 1988 |
| Zurich Insurance Company (U.K.) Limited | Professional & scientific | 1942 |
| Zurich International (UK) Limited | Extraterritorial | 1894 |
| Zurich Legacy Solutions Services (UK) Limited | Administrative & support | 1904 |
| Zurich Management Services Limited | Administrative & support | 1992 |
| Zurich Professional Limited | Extraterritorial | 1998 |
| Zurich Specialties London Limited | Administrative & support | 1989 |
| Zurich UK General Employee Services Limited | Administrative & support | 1999 |
| Zurich UK General Services Limited | Administrative & support | 1999 |
| Zurita Investments Limited | Real estate | 2024 |
| Zymot Fertility UK Limited | Wholesale & retail | 2022 |
| Zyzi Ltd | Other services | 2024 |