| Asdj Ltd | Wholesale & retail | 2025 |
| Aseda Supermarket Ltd | Wholesale & retail | 2025 |
| Asees Estates Limited | Real estate | 2017 |
| Asees PVT Limited | Hospitality | 2024 |
| Aser Trading Limited | Hospitality | 2017 |
| Asfionix Ltd | Construction | 2025 |
| Asghar Events Limited | Hospitality | 2017 |
| Asghar Vending Ltd | Wholesale & retail | 2025 |
| Asgs Financial Services Ltd | Professional & scientific | 2025 |
| ASH Biomedical Integrated Services Limited | Wholesale & retail | 2011 |
| ASH Brook the Funeral Directors Ltd | Other services | 2019 |
| ASH Homes Ltd | Real estate | 2020 |
| ASH Housing | Real estate | 2019 |
| ASH Hurst Goring Ltd | Construction | 2018 |
| ASH Maintenance Limited | Construction | 2025 |
| ASH People Partners Ltd | Extraterritorial | 2024 |
| Ashanti Royale Restaurant and Catering Services Limited | Hospitality | 2024 |
| Ashaz Ltd | Wholesale & retail | 2016 |
| Ashb's Investment Ltd | Financial services | 2023 |
| Ashbradley Limited | Health & social care | 2011 |
| Ashbury Satcom Ltd | Information & communication | 2011 |
| Ashenbury Construction Ltd | Construction | 2025 |
| Ashford Piling Limited | Construction | 2023 |
| Ashford Trading International Limited | Construction | 2006 |
| Ashi Solutions Limited | Information & communication | 2007 |
| Ashland Place Finance UK Limited | Financial services | 2025 |
| Ashlar Digital Limited | Information & communication | 2015 |
| Ashleigh Colwill Estates Ltd | Real estate | 2022 |
| Ashley Charles Limited | Real estate | 2003 |
| Ashley Paul Design Ltd | Professional & scientific | 2020 |
| Ashley Wilkinson Associates Ltd | Financial services | 2014 |
| Ashmore & Green Ltd | Real estate | 2023 |
| Ashod Property Limited | Real estate | 2022 |
| Ashonali Limited | Manufacturing | 2015 |
| Ashraf Wealth Property Holdings Limited | Real estate | 2020 |
| Ashrafi Properties (Reading) Limited | Real estate | 2025 |
| Ashrith Properties Limited | Real estate | 2020 |
| Ashtech Solutions Limited | Information & communication | 2014 |
| Ashton Seven Holdings Ltd | Financial services | 2023 |
| Ashton Solar Farm Limited | Energy | 2014 |
| Ashton Supplies Limited | Wholesale & retail | 2007 |
| Ashwood Electrical Contractors Ltd | Construction | 2021 |
| Ashy Limited | Professional & scientific | 2013 |
| ASI Consultants Ltd | Other services | 2022 |
| Asia 4 U Limited | Professional & scientific | 1999 |
| Asia Direct Limited | Professional & scientific | 1996 |
| Asiafora Ltd | Wholesale & retail | 2018 |
| Asian Commodities Limited | Wholesale & retail | 2018 |
| Asian Spice Limited | Hospitality | 1999 |
| Asian Star Directory Limited | Professional & scientific | 2025 |
| Asianknots Limited | Hospitality | 2026 |
| Asim Renovations Ltd | Construction | 2025 |
| Asipita Afolabi Limited | Health & social care | 2025 |
| ASK Business Development Limited | Professional & scientific | 2000 |
| Askahi Limited | Hospitality | 2026 |
| Askar Solutions Ltd | Information & communication | 2023 |
| Askew Associates Limited | Extraterritorial | 2009 |
| Askia Properties Ltd. | Real estate | 2026 |
| Askill Hayward 146 Ltd | Construction | 2025 |
| ASL Accountants Ltd | Professional & scientific | 2007 |
| ASL Nextgen Technologies Ltd | Information & communication | 2026 |
| ASL Urbannest Living Ltd | Real estate | 2026 |
| ASM Interprises Limited | Wholesale & retail | 2025 |
| Asmawa Healthcare Consultancy Limited | Health & social care | 2019 |
| Asmii Limited | Wholesale & retail | 2017 |
| Asmt Group Limited | Health & social care | 2021 |
| ASP LOO Hire Ltd | Administrative & support | 2024 |
| ASP Projects Limited | Professional & scientific | 2001 |
| ASP Technologies Limited | Information & communication | 2015 |
| Aspect Ceilings and Partitions Limited | Construction | 2011 |
| Aspect Fieldpro Ltd | Information & communication | 2023 |
| Aspect Heating and Plumbing (Berkshire) Ltd | Construction | 2018 |
| Aspect Services (Reading) Ltd | Construction | 2013 |
| Aspell's Carpentry & Joinery Ltd | Manufacturing | 2021 |
| Aspen Digital Limited | Information & communication | 2020 |
| Aspenn Enterprise Ltd | Real estate | 2021 |
| Aspentech Ltd. | Information & communication | 1983 |
| Aspinall Mobility Limited | Wholesale & retail | 2009 |
| Aspiration Lodge Limited | Health & social care | 2019 |
| Aspire Abroad UK Ltd | Education | 2025 |
| Aspire Business Enterprises Limited | Transport & logistics | 2015 |
| Aspire Care and Wellbeing Ltd | Health & social care | 2023 |
| Aspire Construction and Building Limited | Construction | 2017 |
| Aspire Developments Holdings Ltd | Real estate | 2019 |
| Aspire Digital Ltd | Professional & scientific | 2007 |
| Aspire Land Limited | Construction | 2015 |
| Aspire Luxury Homes (Eversley) Ltd | Construction | 2017 |
| Aspire Technology Limited | Information & communication | 2017 |
| Aspire Urban Ltd | Real estate | 2026 |
| Aspire Webbs Cottage Ltd | Construction | 2019 |
| Asquiths Bearpawium Ltd | Wholesale & retail | 2022 |
| ASR Solutions Ltd | Wholesale & retail | 2019 |
| Asra Retail Limited | Wholesale & retail | 2024 |
| Assa Abloy Global Solutions UK Limited | Administrative & support | 1991 |
| Assay Birmingham LLP | | 2014 |
| Asset Leasing Group Ltd | Real estate | 2024 |
| Assetone Wealth System Limited | Administrative & support | 2013 |
| Assets Accounting Limited | Professional & scientific | 1996 |
| Assets Financial Services Limited | Extraterritorial | 1999 |
| Assetsgroup Limited | Hospitality | 2013 |