| Arturus Roof Surveys Ltd | Construction | 2023 |
| Artus Trading LP | | 2013 |
| Artwell Development LP | | 2012 |
| Artwood Trading LP | | 2015 |
| Artydough Ltd | Hospitality | 2019 |
| Artyr Tyrkerson Ltd | Manufacturing | 2024 |
| Arum Finance LP | | 2017 |
| Arun Living Ltd | Real estate | 2026 |
| Arun SAM Ltd | Manufacturing | 2019 |
| Aruna Counselling Limited | Health & social care | 2021 |
| Aruna Productions Ltd | Information & communication | 2018 |
| Aruna Solutions Ltd | Wholesale & retail | 2025 |
| Arunastra Trade LP | | 2016 |
| Arunya Ltd | Health & social care | 2024 |
| Arusha Gallery Ltd | Arts & recreation | 2014 |
| Arustina International LP | | 2018 |
| Arval Group Ltd | Other services | 2024 |
| Arvensis Consulting LP | | 2015 |
| Arvico LP | | 2023 |
| Arvion Commerce Ltd | Information & communication | 2026 |
| ARX Petra Limited | Other services | 2012 |
| ARX Rural Brokers Limited | Financial services | 2025 |
| ARX Rural Member Benefits Limited | Administrative & support | 2025 |
| ARX Rural RE Ltd | Financial services | 2023 |
| Arxa Cyber Ltd | Information & communication | 2025 |
| Aryafa LP | | 2012 |
| Aryka Alliance LP | | 2016 |
| Aryonics Ltd | Professional & scientific | 2025 |
| AS Abode GP Limited | Other services | 2024 |
| AS Abode LP | | 2024 |
| AS Clean & Go Ltd | Administrative & support | 2026 |
| AS Company Services Limited | Professional & scientific | 2007 |
| AS Curry House Ltd | Hospitality | 2025 |
| AS Development Trade LP | | 2012 |
| AS Director Limited | Professional & scientific | 2007 |
| AS Endodontics Ltd | Health & social care | 2022 |
| AS IT Solutions Limited | Information & communication | 2025 |
| AS Mikk Ltd | Wholesale & retail | 2022 |
| AS Oakview Property Limited | Real estate | 2026 |
| AS One Property Limited | Real estate | 2026 |
| AS Pro Engineering Ltd. | Professional & scientific | 2014 |
| AS Project Services Limited | Information & communication | 2024 |
| AS Smart Light LP | | 2013 |
| AS the Deer Limited | Manufacturing | 2023 |
| Asac Aero Ltd | Transport & logistics | 2025 |
| Asad Motors Ltd | Transport & logistics | 2025 |
| Asagi Management LP | | 2015 |
| Asai International LP | | 2017 |
| Asake Empire Ltd | Wholesale & retail | 2025 |
| Asbestos Risk Control Ltd | Professional & scientific | 2015 |
| ASC Scotland Limited | Wholesale & retail | 2016 |
| Ascend Online Media Limited | Information & communication | 2005 |
| Ascendant Property Investments Limited | Real estate | 2014 |
| Ascending Group LP | | 2016 |
| ASCENSION88 Ltd | Construction | 2022 |
| Ascent Leadership Ltd | Professional & scientific | 2023 |
| Ascent Platform Limited | Information & communication | 2022 |
| Ascent RNA Limited | Information & communication | 2025 |
| Ascnstudio Ltd | Professional & scientific | 2025 |
| Ascona Assets LP | | 2016 |
| Ascot Business Services L.P. | | 2008 |
| Ascot Developments L.P. | | 2012 |
| Ascot Overseas Trading (UK) L.P. | | 2011 |
| Ascr Limited | Professional & scientific | 2017 |
| Ascus Art & Science | Arts & recreation | 2013 |
| ASD RBS Scottish Limited Partnership | | 2021 |
| ASD Renovations Ltd | Construction | 2025 |
| Asdo Ltd | Administrative & support | 2025 |
| Ase-Schooling Ltd | Education | 2022 |
| Asein Card Ltd | Administrative & support | 2025 |
| Asep Co-Invest I LP | | 2020 |
| Asep General Partner I LLP | | 2020 |
| ASF Armada Co-Invest B L.P. | | 2023 |
| ASF Armada Co-Invest L.P. | | 2023 |
| ASF Atlantic Co-Investment LP | | 2013 |
| ASF Atlas Co-Invest B L.P. | | 2021 |
| ASF Atlas Co-Invest L.P. | | 2021 |
| ASF Atlas L.P. | | 2020 |
| ASF August Co-Invest B L.P. | | 2023 |
| ASF August Co-Invest C L.P. | | 2023 |
| ASF August Co-Invest L.P. | | 2023 |
| ASF B Co-Invest (C) L.P. | | 2019 |
| ASF Blazer Co-Invest B L.P. | | 2021 |
| ASF Blazer Co-Invest L.P. | | 2021 |
| ASF Boomerang Co-Invest B L.P. | | 2025 |
| ASF Boomerang Co-Invest L.P. | | 2025 |
| ASF Cabana Co-Invest B L.P. | | 2025 |
| ASF Cabana Co-Invest L.P. | | 2025 |
| ASF Cape Point Co-Invest L.P. | | 2026 |
| ASF Capri Co-Invest B L.P. | | 2023 |
| ASF Capri Co-Invest L.P. | | 2023 |
| ASF Cascade Co-Invest B L.P. | | 2020 |
| ASF Cascade Co-Invest C L.P. | | 2020 |
| ASF Cascade Co-Invest L.P. | | 2020 |
| ASF Casita Co-Invest B L.P. | | 2026 |
| ASF Casita Co-Invest L.P. | | 2026 |
| ASF Chestnut L.P. | | 2017 |
| ASF Click Co-Invest B L.P. | | 2014 |
| ASF Cloudberry L.P. | | 2019 |
| ASF Clyde Co-Invest B L.P. | | 2021 |