| Arivi Ltd | Real estate | 2025 |
| Ariyadent Group Limited | Health & social care | 2021 |
| Ariz Global Limited | Wholesale & retail | 2026 |
| Arizona Estates (UK) Ltd | Real estate | 2013 |
| Arizona Fried Chicken Grill Kabab Ltd | Hospitality | 2024 |
| Arizona Fried Chicken PVT Ltd | Hospitality | 2026 |
| Arizona Services Ltd | Wholesale & retail | 2023 |
| Arizona Skyline Limited | Information & communication | 2017 |
| Arizone Ltd | Wholesale & retail | 2016 |
| Arjan Consultants Ltd | Information & communication | 2017 |
| Arjean Advisory Limited | Professional & scientific | 2023 |
| Arjin Ltd | Hospitality | 2019 |
| Arjl Ltd | Information & communication | 2026 |
| Arjun Pharma Ltd | Wholesale & retail | 2019 |
| ARK Autoworks Limited | Wholesale & retail | 2024 |
| ARK Business Advisors Limited | Professional & scientific | 2025 |
| ARK Elite Heating & Plumbing Ltd | Construction | 2025 |
| ARK Estates Group Ltd | Real estate | 2023 |
| ARK Furniture Limited | Extraterritorial | 2020 |
| ARK Innovate Limited | Information & communication | 2024 |
| ARK Kitchen LAB Ltd | Hospitality | 2026 |
| ARK Manchester Ltd | Wholesale & retail | 2023 |
| ARK MAR Trading Ltd | Wholesale & retail | 2026 |
| ARK Mobile Ltd | Manufacturing | 2025 |
| ARK Plastering and Damp Proofing Limited | Construction | 2024 |
| ARK Platforms, Europe Limited | Information & communication | 2025 |
| ARK Properties Commercial Ltd | Real estate | 2024 |
| ARK Publication Ltd | Manufacturing | 2020 |
| ARK Traders (Manchester) Limited | Wholesale & retail | 1974 |
| Arkad Asset Management Ltd | Financial services | 2023 |
| Arkad Capital Ltd | Real estate | 2026 |
| Arkan AL Benaa for Contracting Ltd | Other services | 2021 |
| Arkan Aljazir Lilaemal Ltd | Wholesale & retail | 2026 |
| Arkan Office for Engineering Consultations and Works Ltd | Professional & scientific | 2025 |
| Arkane Ltd | Wholesale & retail | 2025 |
| Arkas Property Group Ltd | Real estate | 2023 |
| Arkas Trading Ltd | Wholesale & retail | 2023 |
| Arkenox Ltd | Information & communication | 2024 |
| Arkfw Ltd | Wholesale & retail | 2024 |
| Arkilab Ltd | Professional & scientific | 2020 |
| Arkios Limited | Financial services | 2001 |
| Arkle Debt Service Limited | Administrative & support | 2026 |
| Arkle Group Limited | Professional & scientific | 2025 |
| Arkle Insolvency Ltd | Administrative & support | 2020 |
| Arkos Design & Build Limited | Professional & scientific | 2013 |
| Arkos-It Limited | Construction | 2023 |
| ARL 011 Limited | Energy | 2017 |
| ARL Haulage Limited | Transport & logistics | 2018 |
| ARL Medical Consultancy Ltd | Health & social care | 2023 |
| ARL O09 Limited | Energy | 2017 |
| Arlaform Limited | Administrative & support | 2001 |
| Arlblack Enterprises Limited | Other services | 2022 |
| Arle Investments Limited | Real estate | 2022 |
| Arlec Property Services Ltd | Construction | 2016 |
| Arley Services Limited | Administrative & support | 2016 |
| Arlie Hold Co Limited | Financial services | 2024 |
| Arlington Group Holdings Ltd | Health & social care | 2017 |
| Arlington Health Ltd | Health & social care | 2026 |
| Arlington Infrastructure Limited | Energy | 2018 |
| Arlington Medical Consultancy Limited | Administrative & support | 2010 |
| Arlo AI Ltd | Information & communication | 2026 |
| Arlo Huxley Limited | Wholesale & retail | 2023 |
| Arlow (BRE) Ltd | Real estate | 2024 |
| Arlow (Lapwing) Limited | Real estate | 2023 |
| Arlow Property Group Ltd | Real estate | 2020 |
| Arlukkachase Ltd | Manufacturing | 2021 |
| Arluna Limited | Information & communication | 1997 |
| ARM 786 Limited | Real estate | 2017 |
| ARM Around Care Group Limited | Financial services | 2023 |
| ARM Engineering NW Limited | Construction | 2015 |
| ARM Gate Ltd | Manufacturing | 2026 |
| ARM Motor Traders & Recovery Ltd | Wholesale & retail | 2025 |
| ARM Ventures Ltd | Hospitality | 2020 |
| Arma Compliance Services Ltd | Professional & scientific | 2020 |
| Arma Fashion Limited | Wholesale & retail | 2015 |
| Arma Kitchen Ltd | Wholesale & retail | 2025 |
| Arma Property Developments Ltd | Real estate | 2025 |
| Armaan One Ltd | Hospitality | 2017 |
| Armaclad Ltd | Construction | 2005 |
| Armacoatings (North West) Limited | Professional & scientific | 1995 |
| Armadale Investments Limited | Real estate | 2018 |
| Armagh Assets (NO 2) Limited | Extraterritorial | 2016 |
| Armagh Assets (NO 3) Limited | Extraterritorial | 2016 |
| Armagh LP | | 2018 |
| Armani & Kennedy Nexus Ltd | Hospitality | 2025 |
| Armans Fashion Limited | Wholesale & retail | 2026 |
| Armany West Limited | Professional & scientific | 2015 |
| Armar Bathrooms Ltd | Construction | 2022 |
| Armc Property Limited | Real estate | 2025 |
| Armchair General Games Ltd | Manufacturing | 2023 |
| Armela Properties Ltd. | Transport & logistics | 2024 |
| Armicathur Limited | Health & social care | 2019 |
| Armin Deeg Ltd | Households | 2023 |
| Armistead Property Assets Limited | Real estate | 2021 |
| Armix Concrete Services Ltd | Administrative & support | 2017 |
| Armod Property Ltd | Real estate | 2024 |
| Armos Security Ltd | Administrative & support | 2026 |
| Armoss Services Limited | Administrative & support | 2015 |
| Armour Bidco Limited | Financial services | 2018 |
| Armour Care Services Ltd | Health & social care | 2021 |