| Archishil Assets Ltd | Real estate | 2025 |
| Archishil Holdings Ltd | Financial services | 2025 |
| Archishil Ltd | Real estate | 2019 |
| Archishil Properties Ltd | Real estate | 2025 |
| Architectural & Structural Engineers Ltd | Construction | 2019 |
| Architorium Developments Ltd | Construction | 2013 |
| Architorium Limited | Construction | 2010 |
| Archopinion Ltd | Information & communication | 2022 |
| Archway Road Developments Ltd | Real estate | 2015 |
| Arcs 67 Ltd | Real estate | 2023 |
| Arctic Blast Ltd | Energy | 2025 |
| Arcticedge Climate Solutions Ltd | Manufacturing | 2025 |
| Arcticedge Solution Limited | Construction | 2025 |
| Arcvelop Folca Ltd | Real estate | 2026 |
| Arcvelop Holdings Ltd | Real estate | 2022 |
| Arcvelop Investments Ltd | Real estate | 2020 |
| Arcvelop X Holdings Limited | Real estate | 2019 |
| Arcvelop X Ltd | Real estate | 2024 |
| Arda(Bd) Ltd | Hospitality | 2025 |
| Ardecos & Sons Ltd | Other services | 2024 |
| Arden House Building Ltd | Financial services | 2020 |
| Arden House Group Ltd | Financial services | 2020 |
| Ardeoz Ltd | Construction | 2026 |
| Ardhikan Limited | Other services | 2022 |
| Arena Phone (UK) Ltd | Other services | 2014 |
| Arete Real Estate Limited | Real estate | 2025 |
| Arexus Ltd | Real estate | 2025 |
| Arfi Security Services Ltd | Administrative & support | 2026 |
| ARG SOL Ltd | Information & communication | 2026 |
| Argentcrest Build & Design Ltd | Construction | 2026 |
| Arges Supermarket Ltd | Wholesale & retail | 2019 |
| Argus Drivers Ltd | Transport & logistics | 2024 |
| ARH Consultancy Ltd | Real estate | 2013 |
| Arham Motors Limited | Wholesale & retail | 2021 |
| Arhin Visuals Limited | Administrative & support | 2015 |
| Arhu Ltd | Wholesale & retail | 2025 |
| Arhy LLP | | 2020 |
| ARI London Limited | Wholesale & retail | 2024 |
| Arian Builders Ltd | Construction | 2025 |
| Arias Shine Ltd | Other services | 2025 |
| Aridor Limited | Wholesale & retail | 2006 |
| Aridyl Holdings Ltd | Real estate | 2022 |
| Aridyl Investments Ltd | Real estate | 2026 |
| Ariel's Creations Limited | Wholesale & retail | 2023 |
| Ariella's Bows and Sparkles Ltd | Wholesale & retail | 2023 |
| Arif & Sons Ltd | Construction | 2016 |
| Arif Master Limited | Administrative & support | 2013 |
| Arisesoft Solutions Ltd | Information & communication | 2013 |
| Arivukkathir Consultancy Ltd | Information & communication | 2014 |
| Ariya Halal Food Ltd | Wholesale & retail | 2022 |
| Ariya Investments Limited | Real estate | 2010 |
| Ariz Property Services Ltd | Manufacturing | 2025 |
| ARJ Investments Limited | Real estate | 2008 |
| Arjv Ltd | Real estate | 2023 |
| ARK & Smith Plumbing and Maintenance Ltd | Construction | 2026 |
| ARK Digitech Ltd | Information & communication | 2015 |
| ARK Hire and Recruitment Ltd | Administrative & support | 2021 |
| ARK Innovations Consulting Engineers Ltd | Professional & scientific | 2023 |
| ARK Mortgages Ltd | Financial services | 2020 |
| ARK Properties London Ltd | Real estate | 2022 |
| ARK Property Developer Ltd | Real estate | 2015 |
| ARK Residential Limited | Real estate | 2017 |
| ARK Services London Ltd | Construction | 2025 |
| ARK UK PTY Ltd | Wholesale & retail | 2025 |
| Arka Developers Limited | Construction | 2025 |
| Arkaya Ltd | Administrative & support | 2025 |
| Arkbell Limited | Construction | 2011 |
| Arkbuildersuk Ltd | Other services | 2022 |
| Arki Properties Limited | Real estate | 2021 |
| Arki Technologies Ltd | Information & communication | 2025 |
| Arkita Limited | Construction | 2004 |
| Arks Design Studio Limited | Professional & scientific | 2013 |
| Arks Recruitment & Contracts Ltd | Administrative & support | 2023 |
| Arks Tech Ltd | Information & communication | 2021 |
| Arkss Design Limited | Construction | 2016 |
| Arkss Redesign Studio Limited | Professional & scientific | 2024 |
| Arkuratek Ltd | Information & communication | 2026 |
| Arky Interior Ltd | Professional & scientific | 2020 |
| Arla Cafe Ltd | Hospitality | 2025 |
| Arlene (UK) Ltd | Other services | 2008 |
| Arlene Properties Limited | Real estate | 2020 |
| ARM Products Ltd | Wholesale & retail | 2023 |
| ARM Property Group Ltd | Real estate | 2023 |
| ARM Traders Ltd | Wholesale & retail | 2020 |
| Armaan CA Ltd | Wholesale & retail | 2022 |
| Armada Baltic Ltd | Wholesale & retail | 2021 |
| Arman Ride Limited | Wholesale & retail | 2017 |
| Armanjot Ltd | Construction | 2025 |
| Armarni’S Ltd | Information & communication | 2025 |
| Armas DE LOS Reyes Limited | Hospitality | 2014 |
| Armaya Technologies Ltd | Information & communication | 2026 |
| Armc Gear Ltd | Wholesale & retail | 2022 |
| Armiti Trading UK Limited | Wholesale & retail | 2019 |
| Armiza Ltd | Wholesale & retail | 2025 |
| Armored Services Limited | Administrative & support | 2024 |
| Armoured Doors Ltd | Administrative & support | 2021 |
| Armours Security Services Ltd | Other services | 2017 |
| Armstrong Security Gaurds Limited | Financial services | 2022 |
| Armstrong York Asbestos Environmental Limited | Professional & scientific | 2003 |
| Arna&Premium Ltd | Wholesale & retail | 2025 |