| Aureus Real Estate Ltd | Real estate | 2024 |
| Aurev Pulse Ltd | Information & communication | 2026 |
| Auri Pilates Studios Ltd | Health & social care | 2021 |
| Auri.Systems Ltd | Wholesale & retail | 2024 |
| Auricles (Yorkshire) Limited | Health & social care | 2025 |
| Aurixa Digital Ltd | Information & communication | 2026 |
| Aurora Cloud LLP | | 2024 |
| Aurora Dance Academy Leeds Ltd | Arts & recreation | 2025 |
| Aurora Eclipse Ltd | Financial services | 2025 |
| Aurora Install Limited | Construction | 2017 |
| Aurora Project Consultancy Ltd | Professional & scientific | 2021 |
| Aurora Properties Global Ltd | Real estate | 2024 |
| Aurora Skin and Aesthetics Limited | Health & social care | 2026 |
| Aurora's Temple Limited | Other services | 2025 |
| Aurum Asset Group Limited | Financial services | 2025 |
| Aurum Dental Clinic Limited | Health & social care | 2025 |
| Aurum Dental Limited | Health & social care | 2023 |
| Aurum Vista Limited | Real estate | 2025 |
| Ausmatt Limited | Health & social care | 2018 |
| Auspice Holdings Limited | Administrative & support | 2021 |
| Auspicious Monkey Property Ltd | Real estate | 2025 |
| Austhorpe Solutions Limited | Construction | 2016 |
| Austin & Austin Holdings Ltd | Real estate | 2025 |
| Austin & Austin Properties Limited | Real estate | 2019 |
| Austin Accounts & Tax Limited | Professional & scientific | 2007 |
| Austin Hayes Limited | Manufacturing | 1990 |
| Austin Hayes UK Limited | Real estate | 2000 |
| Austin House Management Co. Ltd | Real estate | 2002 |
| Austin Investment Property Management Ltd | Real estate | 2021 |
| Austin Kemp Solicitors Limited | Professional & scientific | 2009 |
| Austin Signs Limited | Extraterritorial | 2000 |
| Austin Tech Solutions Ltd | Information & communication | 2025 |
| Austin Williamson Limited | Extraterritorial | 2017 |
| Austin's Gardens Limited | Administrative & support | 2018 |
| Autec MOT & Service Ltd | Wholesale & retail | 2024 |
| Authentia Fine Foods Limited | Wholesale & retail | 2019 |
| Authentia Limited | Wholesale & retail | 2025 |
| Authentic Chefs Ltd | Hospitality | 2023 |
| Authentic Constructions and Roofing Ltd | Construction | 2015 |
| Authentic Consultancy Services Ltd | Professional & scientific | 2015 |
| Authentic Healthcare Services Ltd | Health & social care | 2018 |
| Authentic Locks Ltd | Other services | 2014 |
| Autism Arena CIC | Education | 2024 |
| Autism Arena Services Ltd | Education | 2024 |
| Autism Bricks UK CIC | Health & social care | 2016 |
| Autism Partnership Leeds Limited | Education | 2007 |
| Autism Partnership London Limited | Education | 2022 |
| Autism Partnership UK Limited | Financial services | 2022 |
| Auto Assist (Yorkshire) Ltd | Wholesale & retail | 2019 |
| Auto Creative Ltd | Information & communication | 2013 |
| Auto Expert Consultancy Ltd | Professional & scientific | 2025 |
| Auto Flavius Ltd | Wholesale & retail | 2024 |
| Auto House 1 Ltd | Wholesale & retail | 2022 |
| Auto KET Locksmiths Ltd | Wholesale & retail | 2023 |
| Auto Logistica Ltd | Wholesale & retail | 2017 |
| Auto MAP Ltd | Professional & scientific | 2015 |
| Auto P Fect (Leeds) Ltd | Wholesale & retail | 2019 |
| Auto Point Leeds Ltd | Other services | 2012 |
| Auto Recovery & Car Sales Ltd | Wholesale & retail | 2021 |
| Auto Response Limited | Wholesale & retail | 2026 |
| Auto Resprays Limited | Other services | 2013 |
| Auto Sales Group Ltd | Wholesale & retail | 2016 |
| Auto Service Repair AM Ltd | Wholesale & retail | 2024 |
| Auto Tech Leeds Ltd | Wholesale & retail | 2015 |
| Auto Tech Morley Limited | Wholesale & retail | 2026 |
| Auto Tech MOT Centre Leeds Ltd | Wholesale & retail | 2024 |
| Auto Tech Repair Centre Leeds Ltd | Wholesale & retail | 2024 |
| Auto Trade ELY Ltd | Transport & logistics | 2024 |
| Auto World Cars Parts & Accessories Ltd | Wholesale & retail | 2026 |
| Auto Worx Leeds Ltd | Wholesale & retail | 2022 |
| AUTO-4 Limited | Wholesale & retail | 1984 |
| Auto-Charge (UK) Limited | Manufacturing | 2001 |
| Autobahn Musik Limited | Information & communication | 2015 |
| Autoband Ltd | Wholesale & retail | 2025 |
| Autobase Car Sales Limited | Wholesale & retail | 2022 |
| Autocentre Leeds Ltd | Wholesale & retail | 2024 |
| Autocert Ltd | Wholesale & retail | 2019 |
| Autocube Limited | Professional & scientific | 2008 |
| Autodata Information Services Limited | Information & communication | 1979 |
| Autodata Limited | Information & communication | 1972 |
| Autodata Publishing Group Limited | Information & communication | 1975 |
| Autofix Leeds Limited | Wholesale & retail | 2021 |
| Autoflex Limited | Wholesale & retail | 2013 |
| Autogate Access Ltd | Construction | 2015 |
| Autohaus Bespoke Ltd | Administrative & support | 2019 |
| Autohotspott Limited | Wholesale & retail | 2023 |
| Autologic Transport Ltd | Transport & logistics | 2017 |
| Automac Leeds Ltd | Wholesale & retail | 2025 |
| Automate Cars Limited | Wholesale & retail | 2024 |
| Automate Solutions Ltd | Information & communication | 2024 |
| Automated Information Technology Ltd | Information & communication | 2023 |
| Automated QA Limited | Information & communication | 2012 |
| Automated Reach Group Limited | Information & communication | 2019 |
| Automation Advisory Ltd | Information & communication | 2025 |
| Automind Limited | Wholesale & retail | 2021 |
| Automosales Ltd | Wholesale & retail | 2025 |
| Automotive & Industrial Consumables Limited | Other services | 2010 |
| Automotive Customisation Specialists Ltd | Wholesale & retail | 2023 |
| Automotive Mentors Ltd | Education | 2017 |
| Automotive Technical Services & Mot's Ltd | Wholesale & retail | 2018 |