| Aoife Management Ltd | London | 2010 |
| Aoifemay Limited | Hertford | 2018 |
| Aoifinity Management Ltd | Glasgow | 2026 |
| Aoire Ltd | Dungannon | 2021 |
| Aoise Ltd | London | 2025 |
| AOK Associates Limited | Edgbaston | 2024 |
| AOK Consultancy Ltd | Bury St. Edmunds | 2025 |
| AOK Limited | London | 2008 |
| AOK Standish Ltd | Stonehouse | 2023 |
| AOK Tyre & Plastic Recycling(Environmental) Ltd | Glasgow | 2025 |
| Aok-Hv Ltd | Warrington | 2017 |
| Aokca Limited | Crawley | 2024 |
| AOL Consult Limited | Knutsford | 2019 |
| AOL Consulting Ltd | Woking | 1997 |
| AOL Investment Limited | Rochester | 2020 |
| AOL Marketing Limited | Liverpool | 2015 |
| AOL Sourcing and Support Services Ltd | Colchester | 2019 |
| Aolaw Ltd | Harlow | 2019 |
| Aolaw Practice Ltd | Harlow | 2024 |
| AOM + MO Ltd | Bolton | 2017 |
| AOM Associates Ltd | Reading | 2021 |
| AOM Construction Ltd | Chelmsford | 2024 |
| AOM Consulting Ltd | Upminster | 2020 |
| AOM Electronics Ltd | Bedford | 2012 |
| AOM Solutions Limited | Swansea | 2016 |
| Aoma OIL Ltd | Cobham | 2022 |
| Aomi Labs Ltd | London | 2026 |
| Aomkara Holdings Limited | London | 1996 |
| Aomm Consulting Ltd | Potters Bar | 2022 |
| AON Accountancy Limited | Glasgow | 2017 |
| AON Analytics Ltd | London | 2022 |
| AON Assessment (UK) Limited | London | 2013 |
| AON Auto Consultant Limited | Oxford | 2010 |
| AON Consulting Financial Services Limited | Farnborough | 1950 |
| AON Consulting Limited | Farnborough | 1995 |
| AON Global Holdings PLC | London | 2014 |
| AON Global Limited | London | 2011 |
| AON Investments Limited | London | 2006 |
| AON Management Limited | Milton Keynes | 2002 |
| AON Product Design Ltd | Newhaven | 2017 |
| AON Solutions UK Limited | London | 2002 |
| Aona Digital Limited | Leigh-On-Sea | 2025 |
| Aona Environmental Consulting (UK) Ltd | Enniskillen | 2019 |
| Aonach Engineering Ltd | South Queensferry | 2025 |
| Aone Controls Ltd | Altrincham | 2022 |
| Aonet Ltd | Harrow | 2019 |
| Aonghusa Ventures Ltd. | Belfast | 2011 |
| Aonia Consulting Limited | Wimborne | 2019 |
| AOO Company Limited | Houghton Le Spring | 2017 |
| AOO Global Limited | Hounslow | 2021 |
| AOO Services Ltd | London | 2024 |
| AOO Specialist Indemnity Scheme Ltd | Yeovil | 2010 |
| AOP Group Limited | London | 2026 |
| AOP Title Limited | Camberley | 2001 |
| Aopa Limited | Sevenoaks | 1997 |
| Aopc Limited | Peterborough | 2013 |
| Aopclearning Ltd | Glasgow | 2025 |
| Aoprosolutions Limited | Mitcham | 2026 |
| Aoqs Limited | Ashford | 2025 |
| AOR Legal Ltd | Staines-Upon-Thames | 2022 |
| AOR2 Ltd | Liverpool | 2016 |
| Aora Health Limited | Chippenham | 2024 |
| Aoradh Ltd | Glasgow | 2025 |
| Aoraki Consulting Limited | Witney | 2024 |
| Aorangi Consulting Limited | London | 2011 |
| Aord Project Management Limited | London | 2017 |
| Aore Consulting Limited | London | 2021 |
| Aori Consulting Ltd | Leigh-On-Sea | 2021 |
| Aorist Consulting Limited | London | 2000 |
| Aorta Sales Limited | Pershore | 2006 |
| Aorupa Holland Design Limited | Old Hatfield | 2012 |
| AOS Accountants Ltd | Orpington | 2024 |
| AOS Consultancy Ltd | Swansea | 2025 |
| AOS Consulting Limited | Milton Keynes | 2013 |
| AOS Contractor Ltd | Birmingham | 2023 |
| AOS Cooling & Heating Limited | Brentwood | 2014 |
| AOS Engineering Services Limited | Bournemouth | 2019 |
| AOS Group Ltd | Benfleet | 2026 |
| AOS Growth Consulting Ltd | Team Valley Gateshead | 2026 |
| AOS RC Ltd | Horwich | 2025 |
| AOS Services and Consultancy Limited | Milton Keynes | 2018 |
| AOS Services Ltd | London | 2022 |
| AOS Solutions Limited | Wadhurst | 2016 |
| AOS Utilities Limited | Ashton-Under-Lyne | 2013 |
| Aosurgical Ltd | Nottingham | 2019 |
| AOT Business Services Limited | London | 2011 |
| AOT Consulting Limited | London | 2000 |
| AOT Design Ltd | Wrotham Heath | 2023 |
| AOT Professional Accountants Limited | Chelmsford | 2024 |
| Aota Studio Ltd | London | 2016 |
| Aotahi Ltd | Liverpool | 2025 |
| Aotea Associates Limited | Westerham | 2009 |
| Aotea Design Ltd | Swansea | 2012 |
| Aotea Engineering Limited | Derby | 2013 |
| Aotearoa Limited | Edinburgh | 1998 |
| Aotearoa Pathology Outsourcing Ltd | London | 2023 |
| Aoto Ltd | Mold | 2021 |
| Aotps Ltd | Eastcote | 2020 |
| Aotra Limited | Ripon | 2003 |
| Aotrom Accounting Services Limited | London | 2025 |