| APF Developments Limited | Extraterritorial | 2016 |
| Apichai Solutions Limited | Information & communication | 2010 |
| Appletree Strategic Land Ltd | Extraterritorial | 2026 |
| Appletree Ventures Ltd | Construction | 2015 |
| Appsana Limited | Information & communication | 2014 |
| Apptitude Media Limited | Professional & scientific | 2026 |
| Apsu USA Limited | Information & communication | 2016 |
| Aptork Ltd | Information & communication | 2018 |
| Aqua Beans Ltd | Arts & recreation | 2016 |
| ARC Displays Limited | Manufacturing | 2007 |
| ARC Displays UK Group Ltd | Financial services | 2025 |
| Archer Automotive Solutions Limited | Wholesale & retail | 2018 |
| Archer Enterprises Limited | Other services | 2025 |
| Archive Digital (Publishing) Limited | Information & communication | 2022 |
| Archiwildish Limited | Professional & scientific | 2014 |
| Arden Build and Construction Limited | Construction | 2019 |
| Arden Footwear Limited | Extraterritorial | 2015 |
| Arden Garages (2011) Limited | Wholesale & retail | 2011 |
| Arden Hotel Waterside LLP | | 2009 |
| Arden House Education Ltd | Education | 2025 |
| Arden Properties Limited | Financial services | 2010 |
| Arden Quarter Limited | Real estate | 2018 |
| Ardenandvale Ltd | Wholesale & retail | 2026 |
| AREA51 Automotive Ltd | Wholesale & retail | 2025 |
| ARJ Consultancy Limited | Professional & scientific | 2022 |
| ARK Signalling Consultancy Ltd | Professional & scientific | 2011 |
| Arkenstone Trading Ltd | Wholesale & retail | 2014 |
| Arkheia Ltd | Information & communication | 2026 |
| Arlingclose Holdings Limited | Financial services | 2021 |
| Arlingclose Services Limited | Extraterritorial | 2013 |
| Armadillo Golf Ltd | Wholesale & retail | 2023 |
| Armour Golf UK Limited | Professional & scientific | 2025 |
| Armstrong Advisory Services Limited | Professional & scientific | 2016 |
| ARO KCA Ltd | Transport & logistics | 2016 |
| Aroma Treatments Limited | Administrative & support | 2010 |
| Arppa Technologies UK Ltd | Information & communication | 2024 |
| Arquebus Solutions Limited | Professional & scientific | 2012 |
| Arrow and Alne Ltd | Information & communication | 2022 |
| Arrow Publishing Limited | Information & communication | 2002 |
| Art Decor Painting Contractors Limited | Other services | 2016 |
| Artisan Coffee Solutions Ltd | Extraterritorial | 2014 |
| Artisan Marquees Limited | Administrative & support | 2014 |
| Arts Rising Collective - Stratford on Avon Community Interest Company | Arts & recreation | 2021 |
| ARV Consulting Limited | Professional & scientific | 2019 |
| Arwinoso Freehold Management Ltd | Households | 2014 |
| AS Grill Ltd | Hospitality | 2025 |
| ASB Rose Ltd | Real estate | 2019 |
| Ascw Ltd | Financial services | 2016 |
| ASH Crescent Capital Limited | Real estate | 2023 |
| ASH Property Investments Limited | Real estate | 2019 |
| Ashbourne Park Limited | Hospitality | 2022 |
| Ashbridge Developments Limited | Construction | 2006 |
| Ashf Consulting Limited | Professional & scientific | 2019 |
| Ashlane Construction Limited | Construction | 2002 |
| Ashlane Group Limited | Professional & scientific | 2022 |
| Ashlane Plant Hire Ltd | Administrative & support | 2017 |
| Aska Consulting Ltd | Professional & scientific | 2019 |
| Aspen (SUA) Limited | Financial services | 2018 |
| Aspey Energy Services Ltd | Construction | 2021 |
| Aspire Beauty & Hair Ltd | Other services | 2012 |
| Aspire Logic Ltd | Extraterritorial | 2002 |
| Associated Energy Consultants Ltd | Professional & scientific | 2023 |
| Association Management Services Limited | Administrative & support | 2020 |
| Astratium Ltd | Manufacturing | 2022 |
| Astratto Creative Ltd | Information & communication | 2025 |
| Astwood Properties Limited | Real estate | 2016 |
| Asylaz Limited | Wholesale & retail | 2012 |
| AT 4X4 Limited | Administrative & support | 2007 |
| AT8 Group Limited | Information & communication | 2021 |
| Atherstone Close Ltd | Real estate | 2025 |
| Atlantic Exchange Ltd | Information & communication | 2022 |
| Atlantic View Title Limited | Hospitality | 2016 |
| Atom Advisory Limited | Professional & scientific | 2022 |
| ATS Electrical Solutions Limited | Construction | 2020 |
| Attuned Consulting Limited | Professional & scientific | 2026 |
| Auri Sport Limited | Wholesale & retail | 2025 |
| Auto Stop Stratford Ltd | Wholesale & retail | 2020 |
| Autobush Limited | Wholesale & retail | 2012 |
| Autodal Engineering Limited | Professional & scientific | 2022 |
| Automate Engineering Services Ltd | Professional & scientific | 2012 |
| AVA Catering Ltd | Hospitality | 2017 |
| AVA Consulting Holdings Ltd | Professional & scientific | 2022 |
| Aveley Homes Limited | Real estate | 1974 |
| Avenue House Bishopton (Management) Limited | Real estate | 1981 |
| Aver Property General Partner Limited | Real estate | 2018 |
| Aver Property Limited Partnership | | 2018 |
| Averon Consulting Ltd | Professional & scientific | 2026 |
| Aviagen European Holdings Limited | Financial services | 2009 |
| Aviagen International Finance Four Limited | Financial services | 2003 |
| Aviagen International Finance Limited | Financial services | 2003 |
| Aviagen International Finance One Limited | Financial services | 2003 |
| Aviagen International Finance Two Limited | Financial services | 2003 |
| Aviagen Limited | Agriculture & fishing | 1982 |
| Avon Accessories Ltd | Wholesale & retail | 2026 |
| Avon Architecture Limited | Professional & scientific | 2018 |
| Avon Boating Services Ltd | Manufacturing | 2023 |
| Avon Boiler Care Limited | Manufacturing | 2002 |
| Avon Consulting Group Ltd | Administrative & support | 2025 |
| Avon Courier Services Ltd | Transport & logistics | 2019 |
| Avon Equipment Sales Limited | Manufacturing | 1995 |