| Andy Dale Holdings Ltd | Financial services | 2022 |
| Andy Dale Productions Ltd | Information & communication | 2022 |
| Andy Dale Writes Limited | Information & communication | 2015 |
| Andy Evans Heating and Plumbing Services Ltd | Construction | 2023 |
| Andys Mower Servicing Ltd | Manufacturing | 2026 |
| Anfamed Limited | Health & social care | 2019 |
| Angel Adam Cleaning Ltd | Administrative & support | 2025 |
| Anglo Asian Footwear Limited | Wholesale & retail | 2023 |
| Angry Chaffinch Ltd | Information & communication | 2011 |
| Anisha & Amrita Investments Limited | Extraterritorial | 2013 |
| Anjum Design Limited | Professional & scientific | 2010 |
| Anjum Developments Ltd | Construction | 2019 |
| Anjum Holdings Ltd | Financial services | 2019 |
| Anjum Properties Ltd | Real estate | 2017 |
| Anksot Ltd. | Professional & scientific | 2015 |
| Annakins Ltd | Real estate | 2023 |
| Anne Westwood Consulting Ltd | Extraterritorial | 2017 |
| Annyshair Limited | Manufacturing | 2025 |
| ANP Media Holdings and Investments Ltd | Financial services | 2024 |
| Anqaa Ltd | Wholesale & retail | 2025 |
| Antalya Turkish Style Ltd | Other services | 2025 |
| Anthony Ace Smith Ltd | Arts & recreation | 2024 |
| Anthony Charles Homes Limited | Real estate | 2010 |
| Anthony Jones Telecommunications Ltd | Information & communication | 2019 |
| Anvilclover Ltd | Transport & logistics | 2019 |
| Anytime Home Care Ltd | Administrative & support | 2023 |
| Anzu Bella Ltd | Wholesale & retail | 2024 |
| AO2 Heating & Plumbing Ltd | Construction | 2025 |
| AON Installations Limited | Construction | 2020 |
| AP Architecture Limited | Professional & scientific | 2006 |
| AP Auto Ltd | Wholesale & retail | 2026 |
| AP Lewis Electrical Ltd | Construction | 2026 |
| AP Lifting Gear Company Ltd. | Wholesale & retail | 2010 |
| AP Scientific Ltd | Professional & scientific | 2026 |
| AP SD Seventy Five Limited | Wholesale & retail | 2025 |
| Apex Automotive Engineering Limited | Wholesale & retail | 2012 |
| Apex Loft Conversions & Extensions Ltd | Construction | 2018 |
| Apex Meridian Partners Ltd | Administrative & support | 2025 |
| APF Courier Services Ltd | Transport & logistics | 2019 |
| APK Design Ltd | Manufacturing | 2023 |
| Appcure Emea Limited | Financial services | 2024 |
| Appleton Plumbing and Heating Ltd | Construction | 2024 |
| Appointments Buddy Franchise Limited | Other services | 2023 |
| Appointments Buddy Limited | Other services | 2019 |
| Approved Adaptations Limited | Construction | 2023 |
| Approved Automotive Solutions Ltd | Transport & logistics | 2022 |
| Approved Fabrications Limited | Manufacturing | 2023 |
| Approved Holdings and Investments Ltd | Financial services | 2022 |
| Approved Home Improvements Limited | Construction | 2022 |
| Approved Logistics Ltd | Transport & logistics | 2026 |
| Approved Properties (Staffordshire) Ltd | Real estate | 2022 |
| Aqua Site Management Solutions Ltd | Construction | 2025 |
| Aqua Solutions Plumbing & Heating Ltd | Construction | 2025 |
| Aquascape Direct Ltd | Construction | 2021 |
| Aquatools Limited | Manufacturing | 1974 |
| Aqula Ltd | Extraterritorial | 2008 |
| AR Build and Developments Ltd | Construction | 2024 |
| AR Fleet Care Ltd | Administrative & support | 2024 |
| AR Holdings Midlands Ltd | Financial services | 2023 |
| AR Kowsor Ltd | Wholesale & retail | 2011 |
| AR Tech Associates Ltd | Professional & scientific | 2019 |
| Aralec Limited | Other services | 2024 |
| Araukana Media Ltd | Information & communication | 2019 |
| Arbsan Tech Ltd | Information & communication | 2024 |
| Arch Control Limited | Construction | 2022 |
| Architectural Glazing Installations Ltd | Construction | 2020 |
| Ardenne Homes Ltd | Construction | 2022 |
| Ardmay Services Limited | Professional & scientific | 2018 |
| AREA51SOLUTIONS Ltd | Information & communication | 2023 |
| Areyha Ltd | Wholesale & retail | 2025 |
| Argae Hall Limited | Hospitality | 2023 |
| Argo (UK) Limited | Construction | 2013 |
| Argo Investment Services Limited | Real estate | 2018 |
| Argut Property Management Ltd | Real estate | 2025 |
| Aries Labs Limited | Information & communication | 2026 |
| Arise Group Limited | Construction | 2025 |
| Ariva Imports Ltd | Wholesale & retail | 2024 |
| ARJ Consumer Holdings Ltd | Wholesale & retail | 2018 |
| ARJ Interior Outlet Limited | Wholesale & retail | 2018 |
| Arjkhem Limited | Wholesale & retail | 2022 |
| ARK Pharm Limited | Wholesale & retail | 2023 |
| Arm-H Logistics Limited | Transport & logistics | 2012 |
| Arnie Interiors Limited | Construction | 2021 |
| Aroonz Fastfood T/A Wallows Ltd | Hospitality | 2021 |
| ARS GAS Service Ltd | Construction | 2016 |
| ARS Property Group Ltd | Real estate | 2022 |
| Art Commercial Management Limited | Professional & scientific | 2013 |
| Artaville Limited | Hospitality | 2024 |
| Artemis Development Solutions Ltd | Professional & scientific | 2015 |
| Artemis Veterinary Clinic Ltd | Professional & scientific | 2026 |
| Artica Ltd | Wholesale & retail | 2020 |
| Arwix Ltd | Wholesale & retail | 2024 |
| Aryamartt Ltd | Wholesale & retail | 2026 |
| AS & MI Ltd | Wholesale & retail | 2022 |
| AS Global Transport Ltd | Transport & logistics | 2021 |
| AS Refrigeration Limited | Manufacturing | 2016 |
| AS RGN Ltd | Health & social care | 2022 |
| AS the Worm Turns Ltd | Administrative & support | 2016 |
| Asbestos Related Conditions-Allied Industrial Diseases | Other services | 2014 |
| ASC Property Developments UK Limited | Construction | 2020 |