| Areolithix Ltd | Administrative & support | 2026 |
| Areon Investments Limited | Extraterritorial | 2021 |
| Areopagus Civic Centre CIC | Other services | 2023 |
| Ares Apollo Ltd | Manufacturing | 2016 |
| Ares Capital Investment Ltd | Hospitality | 2024 |
| Aresco Court Management Company Limited | Households | 1997 |
| Aresh Fashion Ltd | Wholesale & retail | 2024 |
| Arete Fitness Ltd | Arts & recreation | 2024 |
| Arete Procurement Solutions Limited | Other services | 2019 |
| Arevia Ltd | Professional & scientific | 2025 |
| Arew Holdings Limited | Financial services | 2022 |
| Arewa Home of Fashion Ltd | Manufacturing | 2025 |
| Arex Limited | Real estate | 2018 |
| ARF Trading Limited | Wholesale & retail | 2020 |
| Arfa Limited | Wholesale & retail | 2018 |
| Arfa Malik Limited | Wholesale & retail | 2022 |
| Arfa's Palace Ltd | Wholesale & retail | 2025 |
| Arfan Brother Ltd | Real estate | 2026 |
| Arfan Stylish Barber Ltd | Other services | 2024 |
| ARG Logistics Ltd | Transport & logistics | 2013 |
| ARG Valeting Limited | Administrative & support | 2021 |
| Argan Liquid Gold Limited | Manufacturing | 2014 |
| Arganta PHG Ltd | Financial services | 2020 |
| Argenta Investments Limited | Other services | 2022 |
| Argento Living Limited | Real estate | 2023 |
| Argento Ventures Limited | Professional & scientific | 2021 |
| Argentum Construction Ltd | Real estate | 2018 |
| Argo Logistics Group Ltd | Transport & logistics | 2022 |
| Argon Consultants Ltd | Professional & scientific | 2024 |
| Argonoxe Ltd | Construction | 2026 |
| Argonshaw Limited | Real estate | 2022 |
| Argq Designs Limited | Professional & scientific | 2023 |
| Argralca Limited | Real estate | 2020 |
| Arguile Search Contract Limited | Administrative & support | 2023 |
| Arguile Search EOT Limited | Administrative & support | 2023 |
| Arguile Search Limited | Administrative & support | 2012 |
| Argus Fire and Security Ltd | Administrative & support | 1995 |
| Argus Security Systems Limited | Extraterritorial | 2014 |
| Argyle (North West) Construction Ltd. | Construction | 1993 |
| Argyle Construction (Holdings) Limited | Professional & scientific | 2021 |
| Argyle Court Management Company Limited | Real estate | 2007 |
| Argyle Networks Ltd | Administrative & support | 2026 |
| ARH Clinical Ltd | Wholesale & retail | 2026 |
| ARH Enterprises UK Limited | Wholesale & retail | 2025 |
| ARH Estate Ltd | Real estate | 2019 |
| ARH Green Limited | Professional & scientific | 2018 |
| ARH Pharma Limited | Health & social care | 2017 |
| ARH Traders Limited | Professional & scientific | 2022 |
| Arhab Limited | Information & communication | 2025 |
| Arhamz Ltd | Construction | 2022 |
| Arhaniya Ltd | Wholesale & retail | 2025 |
| Arhin Eco-Tidy Ltd | Administrative & support | 2025 |
| Arhuk Ltd | Administrative & support | 2020 |
| ARI Group Ltd | Real estate | 2022 |
| ARI Property Services Ltd | Real estate | 2026 |
| ARI Services Ltd. | Administrative & support | 2018 |
| ARI Smith Illusionist Ltd | Arts & recreation | 2025 |
| ARI Traders Limited | Manufacturing | 2017 |
| Aria Automotive Solutions Ltd | Wholesale & retail | 2024 |
| Aria Commercials Limited | Wholesale & retail | 2014 |
| Aria Properties Ltd | Real estate | 2023 |
| Aria Residential Property Ltd | Real estate | 2023 |
| Aria Sports Limited | Wholesale & retail | 2016 |
| Ariaan Ltd | Real estate | 2026 |
| Ariadni Fine Arts Ltd | Wholesale & retail | 2016 |
| Ariamotive Ltd | Wholesale & retail | 2021 |
| Arian (Catering Suppliers) Limited | Manufacturing | 2014 |
| Arian Heating Limited | Construction | 2019 |
| Ariana Bakery Limited | Wholesale & retail | 2026 |
| Ariana's Closet Ltd | Wholesale & retail | 2023 |
| Arianbiochildcare Limited | Health & social care | 2024 |
| Ariand Engineering Ltd | Professional & scientific | 2013 |
| Ariano Transporting Ltd | Transport & logistics | 2024 |
| Ariba MCR Limited | Real estate | 2023 |
| Aridian Ltd | Professional & scientific | 2026 |
| Aridona Ltd | Wholesale & retail | 2025 |
| Ariel Artificial Intelligence Ltd | Information & communication | 2025 |
| Ariel Enterprises Limited | Education | 2013 |
| Ariel Property Solution Limited | Real estate | 2025 |
| Ariel Technologies Limited | Professional & scientific | 2013 |
| Arieti Limited | Wholesale & retail | 2026 |
| Arif Hajj & Umrah Services Limited | Administrative & support | 2007 |
| Arif Khan Pathan Ltd | Wholesale & retail | 2025 |
| Ariha's Launch Ltd | Wholesale & retail | 2018 |
| Arim Trade Ltd | Wholesale & retail | 2025 |
| Arima Systems Limited | Professional & scientific | 1998 |
| Ario African Recording Industry Organization Ltd | Information & communication | 2019 |
| Ario Takeway Ltd | Hospitality | 2024 |
| Arion Payroll Services Limited | Administrative & support | 1999 |
| Ariona Limited | Professional & scientific | 2000 |
| Arisa Limited | Real estate | 1999 |
| Arisands Limited | Construction | 2000 |
| Arise and Shine Christian Ministries (Manchester) Limited | Other services | 2011 |
| Arise Hosting Limited | Information & communication | 2022 |
| Arise UK Services Limited | Health & social care | 2020 |
| Aristan Realty Limited | Extraterritorial | 2024 |
| Aristo Capital Ltd | Wholesale & retail | 2026 |
| Aristocats Limited | Administrative & support | 2000 |
| Aritek Limited | Wholesale & retail | 2024 |
| Aritek Properties Limited | Real estate | 2024 |