| Austin Holdings (Midlands) Ltd | Erdington | 2025 |
| Austin Investments Unlimited | Cheltenham | 2017 |
| Austin James Capital Ltd | Dundee | 2026 |
| Austin Lakin Clark Ltd | Farnham | 2015 |
| Austin Legacy Limited | Cheadle | 2020 |
| Austin Mango Limited | Hook | 1995 |
| Austin Miller Holdings Ltd | London | 2025 |
| Austin Reynolds Holdings Ltd | Chertsey | 2026 |
| Austinpips Limited | Ruislip, | 2025 |
| Austins Holding Limited | Eastbourne | 2019 |
| Austin’S Group Ltd | Wellington | 2020 |
| Austops Property Limited | Birkin | 2022 |
| Austral Capital Ltd | London | 2026 |
| Austral Holdings UK Ltd | London | 2022 |
| Austral Infrastructure Group (AIG) Ltd | London | 2025 |
| Australia Real Estate Portfolio UK Co Limited | London | 2014 |
| Australian Agri Custodian Ltd | London | 2024 |
| Australian GAS Networks UK 2 Limited | London | 2014 |
| Australian GAS Networks UK Limited | London | 2014 |
| Australiansuper (UK) Ltd | London | 2016 |
| Austwick Berry Limited | Ipswich | 2016 |
| Ausum Group Limited | London | 2022 |
| Auta Group Limited | Stroud | 2018 |
| Autara Group Ltd | Walsall | 2025 |
| Autarch Limited | London | 2003 |
| Autec Holdings Limited | Peterborough | 2019 |
| Authentic Group Ltd | Bromley | 2021 |
| Authentic Property Management Ltd | Wickford | 2018 |
| Author Lead Machine Ltd | London | 2020 |
| Authority Holdings Ltd | London | 2023 |
| Authpay Ltd | London | 2020 |
| Autism Partnership UK Limited | Leeds | 2022 |
| Auto 127 Ltd | London | 2025 |
| Auto Accept Finance Limited | Newcastle | 2007 |
| Auto Assist Scotland Ltd | Glasgow | 2015 |
| Auto Choices Limited | Eversley Cross | 2002 |
| Auto Company UK Holdings Limited | London | 2023 |
| Auto Cruising Ltd | Godalming | 2025 |
| Auto Electrix Group Ltd | Bournemouth | 2025 |
| Auto Finance Online Limited | Wilmslow | 2015 |
| Auto Forge Systems Limited | London | 2026 |
| Auto GB Ltd. | Chipping Norton | 1999 |
| Auto Gearbox Holdings Ltd | Hailsham | 2023 |
| Auto Keys Direct Ltd | Willenhall | 2022 |
| Auto Legal Protection Services Limited | Congleton | 1998 |
| Auto Lender Ltd | Crewe | 2024 |
| Auto Marine Cables International Limited | Worsley | 2019 |
| Auto Node Manufacturing Limited | London | 2026 |
| Auto Surveys Traffic Limited | Leamington Spa | 2025 |
| Auto Trader LMT Limited | London | 2024 |
| Auto Union Finance Limited | Warrington | 2003 |
| Auto Vivendi Holdings Limited | London | 2025 |
| Auto Warranty Limited | Wallsend | 1978 |
| Auto-Enrol Ltd | Storridge | 2010 |
| Auto-Wise Accident Management Specialists Ltd | Glasgow | 2025 |
| Autoaid Assist Ltd | Brierley Hill | 2025 |
| Autobahn Administration Ltd | Salisbury | 2021 |
| Autocare (Holdings) Limited | Stanford-Le-Hope | 2020 |
| Autochek Holdings Limited | Worthing | 2022 |
| Autochx Limited | Chesterfield | 1999 |
| Autoclenz EOT Limited | Cheltenham | 2025 |
| Autoclock Holdings Limited | Gateshead | 2010 |
| Autocom U.K. Limited | Salisbury | 1983 |
| Autocraft Holdings Telford Ltd | Telford | 2019 |
| Autocraft Technology Solutions Limited | Grantham | 2022 |
| Autocroft Holdings Limited | Milton Keynes | 2022 |
| Autodesk UK Holdings Limited | Birmingham | 2016 |
| Autofinity Assist Limited | Warrington | 2011 |
| Autofix Holdings Ltd | Middlesex, Hatch End | 2024 |
| Autofoto Holdings Limited | London | 2024 |
| Autofund Limited | Market Rasen | 2016 |
| Autofutura Holdings Limited | Maidstone | 2009 |
| Autogate Systems Holdings Ltd | Ashford | 2010 |
| Autoglaze Group Ltd | Ystradowen | 2023 |
| Autoglaze Holdings Limited | Wimborne | 2025 |
| Autograph Care Group Finance Ltd | Birmingham | 2018 |
| Autograph Care Group Holdings Ltd | Birmingham | 2018 |
| Autograph Care Group Ltd | Birmingham | 2018 |
| Autograph Consortium Limited | Walsall | 2009 |
| Autograph Finance Ltd | Worcester | 2021 |
| Autograph Insurance Brokers Ltd | Birmingham | 2017 |
| Autoguard Group Limited | Camberley | 2021 |
| Autoguard Holdings Limited | Camberley | 2026 |
| Autoguard Warranties Ltd | Camberley | 2008 |
| Autohome Insurance Limited | Northampton | 1974 |
| Autoleaseplan Ltd | Middlesex | 2004 |
| Autoline Direct Insurance Consultants Limited | Carrickfergus | 1987 |
| Autolodge Hotel Limited | Mold | 1991 |
| Autologic Diagnostics Holdings Limited | Worminghall | 2009 |
| Autologic Holdings Limited | Milton Keynes | 2018 |
| Autolus Therapeutics PLC | London | 2018 |
| Automania Garage Services Group Ltd | Hayes | 2026 |
| Automata Ltd | London | 2023 |
| Automate Clinics Limited | London | 2026 |
| Automate Health Limited | London | 2024 |
| Automate Midco Limited | London | 2026 |
| Automated Building & Energy Controls (Holdings) Ltd. | Tewkesbury | 2021 |
| Automated Environmental Systems Holdings Limited | Ashford | 2023 |
| Automated Training Group Ltd | Nottingham | 2026 |
| Automatic Cars Holdings Limited | London | 2012 |