| AOF Services Limited | Professional & scientific | 2016 |
| Aoife Stack Ltd | Health & social care | 2021 |
| Aone Controls Ltd | Professional & scientific | 2022 |
| AP Asset Management Limited | Construction | 2013 |
| AP Care Homes Limited | Public administration | 2022 |
| AP Property Group Ltd | Construction | 2026 |
| AP Rehabilitation Limited | Health & social care | 2013 |
| Apadana Limited | Real estate | 2006 |
| Apatura Battery - Project Holding 1 Limited | Energy | 2023 |
| Apatura Battery - Project Holding 2 Ltd | Energy | 2023 |
| Apatura Battery Ltd | Energy | 2022 |
| Apatura Construction Ltd | Construction | 2024 |
| Apatura DC Ltd | Information & communication | 2024 |
| Apatura DC Project 1 Ltd | Energy | 2024 |
| Apatura DC Project 10 Ltd | Energy | 2024 |
| Apatura DC Project 11 Ltd | Information & communication | 2025 |
| Apatura DC Project 12 Ltd | Information & communication | 2025 |
| Apatura DC Project 2 Ltd | Energy | 2024 |
| Apatura DC Project 3 Ltd | Energy | 2024 |
| Apatura DC Project 4 Ltd | Energy | 2024 |
| Apatura DC Project 5 Ltd | Energy | 2024 |
| Apatura DC Project 6 Ltd | Energy | 2024 |
| Apatura DC Project 7 Ltd | Energy | 2024 |
| Apatura DC Project 8 Ltd | Energy | 2024 |
| Apatura DC Project 9 Ltd | Energy | 2024 |
| Apatura Direct Power Ltd | Energy | 2023 |
| Apatura Hydrogen Ltd | Energy | 2022 |
| Apatura International Ltd | Energy | 2023 |
| Apatura Ltd | Energy | 2022 |
| Apatura Project 20 Ltd | Energy | 2024 |
| Apatura Project 21 Ltd | Energy | 2024 |
| Apatura Project 23 Ltd | Energy | 2024 |
| Apatura Project 24 Ltd | Energy | 2024 |
| Apatura Project 25 Ltd | Energy | 2024 |
| Apatura Project 26 Ltd | Energy | 2024 |
| Apatura Project 27 Ltd | Energy | 2024 |
| Apatura Project 28 Ltd | Energy | 2024 |
| Apatura Project 29 Ltd | Energy | 2024 |
| Apatura Project 30 Ltd | Energy | 2024 |
| Apatura Project 31 Ltd | Energy | 2024 |
| Apatura Project 32 Ltd | Energy | 2024 |
| Apatura Project 33 Ltd | Energy | 2024 |
| Apatura Project 34 Ltd | Energy | 2024 |
| Apatura Project 35 Ltd | Energy | 2024 |
| Apatura Project Holding 3 Ltd | Energy | 2023 |
| Apatura Project Holding 4 Ltd | Energy | 2023 |
| Apatura Project Holding 5 Ltd | Energy | 2024 |
| Apatura Solar Ltd | Energy | 2014 |
| APC Computer Services Limited | Professional & scientific | 1997 |
| Apcintex Limited | Professional & scientific | 2014 |
| APE USA Ltd | Real estate | 2020 |
| Aperture House Limited | Professional & scientific | 2026 |
| Apex Adventures Limited | Real estate | 2023 |
| Apex Cars & Vans Ltd | Wholesale & retail | 2026 |
| Apex EDS Limited | Professional & scientific | 2022 |
| Apex Finance Solutions Limited | Professional & scientific | 2025 |
| Apex Financial Admin Limited | Financial services | 2026 |
| Apex Flex Limited | Real estate | 2021 |
| Apex Innovative Solutions Limited | Professional & scientific | 2011 |
| Apex IT Hunters Ltd | Information & communication | 2023 |
| Apex Locums Ltd | Health & social care | 2015 |
| Apex Medical Limited | Health & social care | 2026 |
| Apex Practice Limited | Health & social care | 2010 |
| Apex Racing Club Ltd | Arts & recreation | 2025 |
| Apex Sapphire Partners Limited | Professional & scientific | 2024 |
| Apex Software Consultancy Limited | Administrative & support | 2019 |
| Apex Strategy Limited | Professional & scientific | 2021 |
| Apex UK Group Ltd | Information & communication | 2019 |
| Apex Ultra Racing Limited | Arts & recreation | 2025 |
| APH10 Limited | Information & communication | 2022 |
| API Hero Ltd | Information & communication | 2022 |
| Apicius Limited | Professional & scientific | 2009 |
| Apjl Ltd | Professional & scientific | 2015 |
| Aplusi Limited | Professional & scientific | 2022 |
| Apluszee Ltd | Wholesale & retail | 2024 |
| APM International Ltd | Information & communication | 2023 |
| Apogent UK Limited | Administrative & support | 1993 |
| Apollo Kallidus Bidco Limited | Financial services | 2019 |
| Apollo Kallidus Holdco Limited | Professional & scientific | 2019 |
| Apollo Kallidus Midco Limited | Financial services | 2019 |
| Apollo Kallidus Nominee Limited | Professional & scientific | 2020 |
| Apollo Kallidus Topco Limited | Professional & scientific | 2020 |
| Apopo UK | Health & social care | 2019 |
| Appaide Limited | Information & communication | 2022 |
| Appealia Limited | Information & communication | 2022 |
| Appfire UK Limited | Information & communication | 2018 |
| Appian Way Developments Ltd | Construction | 2021 |
| Appian Way Salford Ltd | Construction | 2026 |
| Applebarn Nurseries Limited | Education | 2013 |
| Applebarn Support Services Limited | Construction | 2017 |
| Applehead Media Ltd | Information & communication | 2007 |
| Appleton Mews Management Limited | Households | 1988 |
| Applied Intuition UK Ltd. | Information & communication | 2025 |
| Applied Risk Management Ltd | Professional & scientific | 2026 |
| Applied Technology Architecture Ltd | Information & communication | 2026 |
| Appoint Financial Care Ltd | Financial services | 2024 |
| Appomni UK Limited | Information & communication | 2020 |
| Apra Properties Limited | Real estate | 2025 |
| Apricum Group Ltd | Financial services | 2021 |
| Aprilsql Technology Limited | Information & communication | 2012 |