| AO Time Ltd | Wholesale & retail | 2025 |
| Aobaiisacat Ltd | Wholesale & retail | 2025 |
| AOE Graphics & Innovations Limited | Information & communication | 2011 |
| AOG Technics Limited | Administrative & support | 2015 |
| Aomame Ltd | Arts & recreation | 2022 |
| Aosta Holdings Limited | Financial services | 2024 |
| Aotv Ltd | Information & communication | 2013 |
| Aouled Ltd | Other services | 2025 |
| AOY Limited | Information & communication | 2013 |
| AP Building Ltd | Other services | 2021 |
| AP Creativ Ltd | Information & communication | 2023 |
| AP Digital Ecommerce Ltd | Wholesale & retail | 2025 |
| AP Diverse Ltd. | Manufacturing | 2016 |
| AP General Trading Ltd | Wholesale & retail | 2020 |
| AP Group INT Ltd | Administrative & support | 2025 |
| AP Guard Ltd | Wholesale & retail | 2019 |
| AP Higgs Locksmiths Ltd | Administrative & support | 2018 |
| AP Import Export Ltd | Wholesale & retail | 2017 |
| AP Marine Flooring Ltd | Manufacturing | 2025 |
| AP Recycling Ltd | Water & waste | 2025 |
| AP Retailer Limited | Wholesale & retail | 2025 |
| APA Cars Ltd | Administrative & support | 2016 |
| APA Green Building Consultant Ltd | Professional & scientific | 2024 |
| Apa's Foods Ltd | Hospitality | 2024 |
| Apac Global Solutions Ltd | Real estate | 2017 |
| Apacf Ltd | Administrative & support | 2023 |
| Apaleis Chemicals Limited | Professional & scientific | 2009 |
| Apana Care Solutions Ltd | Health & social care | 2019 |
| Apartlease PVT Ltd | Financial services | 2020 |
| Apartments of London Limited | Hospitality | 2011 |
| Apartmentscompany Ltd | Other services | 2018 |
| Apartshub Ltd | Hospitality | 2019 |
| Apatsa Rose Estates UK Ltd | Real estate | 2022 |
| Apaukandeurope Limited | Other services | 2017 |
| Apcymru Limited | Education | 2002 |
| APD Estates (Birmingham) Ltd | Real estate | 2011 |
| APE Hanger Ltd | Information & communication | 2019 |
| Apec Blue Ltd | Construction | 2015 |
| Apegg Electrical Solutions Limited | Construction | 2022 |
| Apejopo OMO Yoruba Limited | Education | 2020 |
| Apeks Consulting Ltd | Water & waste | 2021 |
| Apelles Augenoptik Ltd. | Administrative & support | 2012 |
| Aperta Blue Chip London Ltd | Wholesale & retail | 2025 |
| Aperture Build Limited | Construction | 2021 |
| Aperture Health Economics Ltd | Professional & scientific | 2025 |
| Apex Appliances South West Ltd | Other services | 2024 |
| Apex CAD Drawing & Planning Ltd | Professional & scientific | 2022 |
| Apex Car Sales and Finance Ltd | Wholesale & retail | 2024 |
| Apex Carpentry and Building Ltd | Manufacturing | 2024 |
| Apex Chambers Management Limited | Professional & scientific | 2018 |
| Apex Chambers Property Ltd | Administrative & support | 2010 |
| Apex Digital Labs Ltd | Wholesale & retail | 2023 |
| Apex Drift Drones Limited | Professional & scientific | 2025 |
| Apex Eyecare Limited | Health & social care | 2011 |
| Apex Facility Management Ltd | Administrative & support | 2012 |
| Apex Financial Money Management Limited | Professional & scientific | 2025 |
| Apex Fincon II Ltd | Information & communication | 2018 |
| Apex Fire and Security Solutions Limited | Administrative & support | 2020 |
| Apex Fitness and Performance Limited | Health & social care | 2018 |
| Apex Glazing & Plastics Ltd | Construction | 2020 |
| Apex Home Installations Ltd | Construction | 2026 |
| Apex Learning Limited | Education | 2017 |
| Apex Marketing Strategies Ltd | Professional & scientific | 2025 |
| Apex Metal Fabricators Ltd | Manufacturing | 2025 |
| Apex Motors Cardiff Ltd | Wholesale & retail | 2024 |
| Apex Motos Limited | Wholesale & retail | 2024 |
| Apex Navid Ltd | Wholesale & retail | 2025 |
| Apex Noir Limited | Wholesale & retail | 2026 |
| Apex Paint Solutions Limited | Manufacturing | 2017 |
| Apex Parcel Limited | Wholesale & retail | 2025 |
| Apex Petroleum Ltd | Other services | 2025 |
| Apex Precision Facilities Limited | Construction | 2025 |
| Apex Project Delivery Ltd | Professional & scientific | 2023 |
| Apex South Ltd | Hospitality | 2024 |
| Apex Telecoms & Energy Limited | Energy | 2020 |
| Apex Trade Hub Ltd | Wholesale & retail | 2025 |
| Apex Transport Planning Ltd | Professional & scientific | 2019 |
| Apex Tyres Ltd | Wholesale & retail | 2024 |
| Apex Vehicle Leasing Ltd | Administrative & support | 2018 |
| Apexhigh Ltd | Wholesale & retail | 2023 |
| Apexis-R&F United Limited | Professional & scientific | 2008 |
| APF Transport (Cardiff) Ltd | Transport & logistics | 2020 |
| Apfl Ltd | Households | 2025 |
| APG Asset Management Ltd | Real estate | 2019 |
| APG Food Tech UK Limited | Hospitality | 2025 |
| APG FS Ltd | Financial services | 2021 |
| APH Solar Seed Limited | Construction | 2025 |
| Aphoena Mart Ltd | Wholesale & retail | 2025 |
| API Connect Ltd | Financial services | 2021 |
| Apihappi Limited | Wholesale & retail | 2015 |
| Apleona - UK Group Limited | Wholesale & retail | 2021 |
| Aplha International Borad Academy Ltd | Education | 2025 |
| Aplm E-Commerce Ltd | Wholesale & retail | 2025 |
| APM Roofing Ltd | Construction | 2021 |
| Apmmedia Ltd | Extraterritorial | 2016 |
| Apocalozzo Limited | Professional & scientific | 2025 |
| Apoharmelon International Ltd | Administrative & support | 2021 |
| Apollient Limited | Information & communication | 2019 |
| Apollo Aviation Consultancy and Management Limited | Manufacturing | 2024 |
| Apollo Beijing Services Co. Limited | Extraterritorial | 2008 |