| ZB Group Ltd | Financial services | 2024 |
| ZB Property Ltd | Real estate | 2013 |
| ZBN Property Ltd | Real estate | 2016 |
| Zecoyi Ltd | Real estate | 2022 |
| Zednet Ltd | Information & communication | 2009 |
| Zeejay Auto Wash and Detailing Ltd | Administrative & support | 2024 |
| Zeel Idrees 381 Limited | Construction | 2024 |
| Zeeworld Limited | Wholesale & retail | 2018 |
| Zefkem Limited | Other services | 2023 |
| Zelvian Ltd | Wholesale & retail | 2025 |
| Zenith Fulfilment Limited | Transport & logistics | 2019 |
| Zenith Motor Company. Limited | Wholesale & retail | 2015 |
| Zenith Property Holdings Ltd | Real estate | 2020 |
| Zenith Property Ltd | Real estate | 2017 |
| Zenithpathways Ltd | Education | 2023 |
| Zephyr Training Ltd | Administrative & support | 2023 |
| Zero Ideas Studio Limited | Information & communication | 2025 |
| Zero Motorcycles UK Ltd | Manufacturing | 2019 |
| Zero Waste Innovations UK Ltd | Wholesale & retail | 2026 |
| Zerwa Ltd | Real estate | 2017 |
| Zeus Accident Repair Group Limited | Financial services | 2023 |
| Zeus Accident Repair London Ltd | Wholesale & retail | 1972 |
| Zeus Accident Repair Properties Limited | Real estate | 2023 |
| Zeus Accident Repair Rochester Ltd | Wholesale & retail | 2018 |
| Zeus Accident Repair Sittingbourne Limited | Wholesale & retail | 2023 |
| Zhyzha Ltd | Information & communication | 2025 |
| Zili Liang Ltd | Wholesale & retail | 2024 |
| Zima Refurbishments Ltd | Construction | 2025 |
| Zimabo Properties Ltd | Real estate | 2024 |
| Zimtech Technology Limited | Information & communication | 2020 |
| Zinclad Limited | Construction | 2017 |
| Zion Solicitors Ltd | Professional & scientific | 2023 |
| Zitel&Cc Ltd | Health & social care | 2019 |
| ZM Trading Limited | Wholesale & retail | 2023 |
| ZN Anaesthetic Solutions Ltd | Health & social care | 2024 |
| ZNA Management Limited | Households | 2022 |
| ZOE BEE Beauty Limited | Manufacturing | 2016 |
| Zoeseth Ventures Ltd | Real estate | 2022 |
| Zoneyear Property Management Limited | Real estate | 1990 |
| Zoracare Limited | Information & communication | 2010 |
| ZQ Home Improvements Limited | Construction | 2025 |
| Zraa Ltd | Real estate | 2024 |
| Zumar Asset Management Ltd | Real estate | 2025 |
| Zumar Capital Ltd | Real estate | 2025 |
| Zuven Technologies Limited | Information & communication | 2025 |
| Zyrotek Ltd | Information & communication | 2026 |