| AQ Zentrix Ltd | Information & communication | 2025 |
| AQA Holdings Ltd | Financial services | 2024 |
| Aqarat Limited | Real estate | 2014 |
| Aqib Anwar Ltd | Other services | 2019 |
| Aqib Capital Limited | Administrative & support | 2024 |
| AQL (Datacentres) Ltd | Extraterritorial | 2013 |
| AQL (DC Operations) Ltd | Extraterritorial | 2013 |
| AQL (DC6) Limited | Professional & scientific | 2014 |
| AQL (Financial) Limited | Financial services | 2013 |
| AQL (Leeds) Ltd | Information & communication | 2002 |
| AQL (Numbering) Ltd | Information & communication | 2014 |
| AQL Holdings Limited | Financial services | 2017 |
| AQL Wholesale Limited | Information & communication | 2004 |
| Aqsa Properties Ltd | Real estate | 2020 |
| Aqua Enviro Limited | Administrative & support | 2023 |
| Aqua Events UK Ltd | Other services | 2017 |
| Aqua Techniques Limited | Water & waste | 2020 |
| Aqua WIN Ltd | Wholesale & retail | 2023 |
| Aquacom Limited | Wholesale & retail | 2021 |
| Aquaconfidence.Co.Uk Ltd | Education | 2025 |
| Aquaeco Limited | Wholesale & retail | 2020 |
| Aquaheat Group Limited | Construction | 2026 |
| Aquaheaven Ltd | Wholesale & retail | 2025 |
| Aqualand Limited | Manufacturing | 1992 |
| Aqualithium Ltd | Professional & scientific | 2019 |
| Aquamarine Systems Limited | Extraterritorial | 1999 |
| Aquarius Equity Holdings Limited | Financial services | 2005 |
| Aquarius Equity Partners Limited | Financial services | 2002 |
| Aquarius Financial Associates Limited | Financial services | 2024 |
| Aquashebah Ministries | Water & waste | 2014 |
| Aquasmith Fire Sprinklers Ltd | Public administration | 2022 |
| Aquasun Investments Limited | Real estate | 1978 |
| Aquasure Technical Ltd | Agriculture & fishing | 2025 |
| Aquatic & Pets Limited | Manufacturing | 2003 |
| Aquatic Blue Ltd | Hospitality | 2019 |
| Aquila Capital Limited | Professional & scientific | 2000 |
| Aquilla Care Limited | Health & social care | 2022 |
| AR & ER Health Limited | Health & social care | 2025 |
| AR & Sons Investment Ltd | Real estate | 2020 |
| AR Cables Limited | Information & communication | 2003 |
| AR Cost & Pricing Ltd | Professional & scientific | 2022 |
| AR Motor Repairs Ltd | Wholesale & retail | 2023 |
| AR Pain Solutions Limited | Health & social care | 2023 |
| AR Property Solutions (Leeds) Ltd | Real estate | 2024 |
| AR Rahman Group Limited | Other services | 2025 |
| AR RO an Ltd | Health & social care | 2018 |
| AR Solutions (Leeds) Ltd | Wholesale & retail | 2020 |
| AR Tennis Ltd | Education | 2022 |
| Ar&D Construction Limited | Construction | 2014 |
| Ar&D Properties Ltd | Real estate | 2024 |
| AR' LAB Ltd | Wholesale & retail | 2022 |
| AR7 Supplies Ltd | Wholesale & retail | 2023 |
| AR95 Ltd | Wholesale & retail | 2024 |
| Araa Foods Ltd | Wholesale & retail | 2024 |
| Araamco Ltd | Hospitality | 2024 |
| Arabella Properties Limited | Real estate | 2018 |
| Arabian Rouge 1982 Limited | Wholesale & retail | 2024 |
| Arabian Rouge Ltd | Wholesale & retail | 2024 |
| Arabic Educational Centre CIC | Education | 2023 |
| Aradore Developments Ltd | Real estate | 2024 |
| Aradore Holdings Limited | Financial services | 2024 |
| Aradore Rentals Ltd | Real estate | 2024 |
| Araft Ltd | Real estate | 2024 |
| Araj Limited | Hospitality | 2023 |
| Aramco Chemicals Limited | Manufacturing | 2020 |
| Aran Curry Insight Ltd | Real estate | 2014 |
| Arancia Juicing Limited | Wholesale & retail | 2009 |
| Aranea Digital Marketing Ltd | Information & communication | 2017 |
| Arapiuns Ltd | Wholesale & retail | 2023 |
| Aras Mini Market Limited | Wholesale & retail | 2026 |
| Aras UFC Middleton Foods Ltd | Hospitality | 2025 |
| Araxis Search Ltd | Professional & scientific | 2025 |
| Araz Leeds Limited | Hospitality | 2016 |
| ARB Facilities Management Ltd | Real estate | 2020 |
| ARB Logistics Limited | Transport & logistics | 2019 |
| ARB Venture Group Ltd | Financial services | 2025 |
| Arbani Limited | Real estate | 2022 |
| Arbaz Logistics Ltd | Transport & logistics | 2025 |
| Arber Pro Finishes Ltd Limited | Construction | 2025 |
| Arbex UK Limited | Financial services | 2024 |
| Arbitan | Financial services | 2018 |
| Arboria Limited | Wholesale & retail | 2014 |
| ARC & KIN Ltd | Health & social care | 2025 |
| ARC (Leeds) Limited | Construction | 2014 |
| ARC 2001 Ltd | Construction | 2022 |
| ARC Building Solutions Limited | Construction | 2007 |
| ARC Cars Ltd | Transport & logistics | 2023 |
| ARC Cosmetics Ltd | Arts & recreation | 2018 |
| ARC Data Systems Limited | Construction | 2005 |
| ARC Electrical & GAS (Leeds) Limited | Professional & scientific | 2016 |
| ARC Engineers Limited | Professional & scientific | 2007 |
| ARC Inspirations Limited | Hospitality | 1999 |
| ARC Investment Holdings Ltd | Financial services | 2021 |
| ARC Investment Properties Ltd | Real estate | 2024 |
| ARC Nominees Limited | Extraterritorial | 2022 |
| ARC Property Services (Leeds) Limited | Construction | 2012 |
| ARC Workwear & PPE Limited | Wholesale & retail | 2015 |
| ARC22 Consulting Limited | Professional & scientific | 2022 |
| Arcade Club Leeds Limited | Arts & recreation | 2017 |
| Arcadia Home Entertainment Limited | Wholesale & retail | 2003 |