| Arista Tech Ltd | Glasgow | 2024 |
| Aristaeus Ltd | London | 2013 |
| Aristarchus Limited | Brecon | 2004 |
| Aristeia Press Limited | London | 2017 |
| Aristi Limited | Birmingham | 2008 |
| Aristifox Ltd | London | 2025 |
| Aristo Intelligence Ltd | Birmingham | 2025 |
| Aristo IT Consultancy Limited | London | 1999 |
| Aristo Networks Ltd | London | 2025 |
| Aristocrat Holding Ltd | London | 2026 |
| Aristocrat Ltd | Hackney | 2011 |
| Aristocrat Music Limited | Northwood Hills | 1964 |
| Aristocratic Productions Limited | London | 2022 |
| Aristodax Ltd | Maidenhead | 2016 |
| Aristofanis Limited | London | 2019 |
| Aristos IT Limited | Wellingborough | 2014 |
| Aristos Partnership Limited | Gloucester | 2016 |
| Aristotix Ltd | London | 2025 |
| Aristotlow Predictions Limited | Virginia Water | 2026 |
| Aristral Ltd | Bristol | 2026 |
| Aristrat & Company Ltd | Mitcham | 2019 |
| Arisu Tech Ltd | London | 2019 |
| Arisyn Ltd | Redditch | 2025 |
| Aritech Solutions Ltd | Oxford | 2021 |
| Aritel Limited | London | 2022 |
| Aritha Technologies Ltd | Leeds | 2023 |
| Arithar Limited | London | 2026 |
| Arithim Ltd | Staines-Upon-Thames | 2026 |
| Arithmia Limited | Edinburgh | 2024 |
| Aritia Ltd | Crowborough | 2021 |
| Aritmetika Ltd | London | 2020 |
| Aritom Technologies Ltd | London | 2026 |
| Arity Solutions Limited | Harrogate | 2012 |
| Arium Limited | London | 1992 |
| Ariva Limited | Northampton | 2022 |
| Arivi Engineering Ltd | Altrincham | 2025 |
| Arivukkathir Consultancy Ltd | Ilford | 2014 |
| Arivuu AI Ltd | Milton Keynes | 2025 |
| Ariweb Ltd | Dagenham | 2025 |
| Arixa Health Limited | Barnet | 2026 |
| Arixa Ltd | London | 2022 |
| Arixcel Limited | Bromley | 2009 |
| Arixen Ltd | Exmouth | 2026 |
| Ariya Cosmos Ltd | Newark | 2024 |
| Ariyan Capital Limited | Shoreham-By-Sea | 2018 |
| Ariyana Ltd | Romford | 2026 |
| Ariych New Vision Ltd | London | 2025 |
| Ariyel Industries Limited | Leeds | 2026 |
| Ariz Ltd | London | 2026 |
| Arize Digital Ltd | London | 2022 |
| Arizeo Ltd | London | 2024 |
| Arizmi Labs Ltd | Chatham | 2026 |
| Arizona Bay Corporation Ltd | Motherwell | 2023 |
| Arizona Multi-Media Limited | Sutton Coldfield | 2006 |
| Arizona Skyline Limited | Manchester | 2017 |
| Arizonamercedesbrodie Ltd | Aberdeen | 2026 |
| ARJ C. Masters Ltd | London | 2026 |
| ARJ Media Ltd | Farnborough | 2021 |
| ARJ Technology Consulting Ltd | Skelmersdale | 2023 |
| Arj.Global Ltd | London | 2018 |
| Arjan Consultants Ltd | Manchester | 2017 |
| Arjan Consulting Limited | Birmingham | 2010 |
| Arjank Limited | Iver | 2017 |
| Arjatec Ltd | London | 2018 |
| Arjay Creative Studios Ltd | Glasgow | 2025 |
| Arjc Consultancy Ltd | Folkestone | 2020 |
| Arje Productions Limited | Dunstable | 2026 |
| Arjl Ltd | Manchester | 2026 |
| Arjo.Dev Ltd | Newcastle Upon Tyne | 2023 |
| Arjs Consultants Limited | Reading | 2014 |
| Arjun & Aishwarya IT Solutions Ltd | Bromley | 2021 |
| Arjun Consultants Ltd | Slough | 2015 |
| Arjun Infotech Limited | Bexleyheath | 2021 |
| Arjun IT Consulting Ltd | Southampton | 2021 |
| Arjun Productions Limited | London | 2012 |
| Arjun Sharma Limited | Uxbridge | 2010 |
| Arjun Software Limited | Basingstoke | 2019 |
| Arjun Technosoft Ltd | Watford | 2016 |
| Arjun Ventures Limited | Northwood | 2017 |
| Arjuna Information Management Ltd | London | 2020 |
| Arjuna Technologies Limited | Newcastle Upon Tyne | 2002 |
| Arjus Limited | North Finchley | 2010 |
| ARK & Blacksmith Ltd | Dundee | 2026 |
| ARK - Ituk Ltd | Crawley | 2019 |
| ARK Accounting and Secretarial Services Ltd | Blackpool | 2020 |
| ARK Assist & Support Ltd | Southampton | 2024 |
| ARK Assistance Limited | Romford | 2024 |
| ARK Automation Limited | Solihull | 2017 |
| ARK Broker Services Ltd | Preston | 2019 |
| ARK Business Intelligence Ltd | Southampton | 2024 |
| ARK Change Management Limited | Watford | 1999 |
| ARK Cloud Ltd | Witham | 2017 |
| ARK Cloud Services Ltd | London | 2015 |
| ARK Cloud Solutions Limited | Isleworth | 2024 |
| ARK CLS Limited | Bedford | 1988 |
| ARK Computer Consultancy Ltd | Basingstoke | 1998 |
| ARK Consultancy Leeds Ltd | Leeds | 2018 |
| ARK Consulting and Associates Limited | Wigan | 2014 |
| ARK Consulting Private Limited | London | 2021 |
| ARK Consulting PVT Ltd | Coventry | 2025 |