| AMW Multiservices Ltd | Wholesale & retail | 2024 |
| AN Apple a Day Limited | Education | 2018 |
| Anakey Ltd | Real estate | 2021 |
| Anandel Ltd | Professional & scientific | 2012 |
| Ananta Assets Limited | Real estate | 2024 |
| Anantasphere Limited | Information & communication | 2025 |
| Anaram Limited | Information & communication | 2004 |
| Anay Consultancy Ltd | Professional & scientific | 2020 |
| Anay Holdings Ltd | Financial services | 2024 |
| Anaya Ventures Limited | Professional & scientific | 2014 |
| Anbe Property Management Limited | Administrative & support | 2012 |
| Anchor Investments Limited | Real estate | 1996 |
| Anchor Patel Limited | Real estate | 2003 |
| Anchorview Limited | Real estate | 2009 |
| Anderson Corporation Limited | Construction | 2023 |
| Anderson Freelance Limited | Professional & scientific | 2016 |
| Anderton Arms Development Ltd | Real estate | 2019 |
| Andora Trade Ltd | Construction | 2014 |
| Andrea Stewart Ltd | Health & social care | 2011 |
| Andrew Brooks Wealth Planning Ltd | Professional & scientific | 2026 |
| Andrew Pearce Commercial Limited | Real estate | 2002 |
| Andrew Pearce Property Consultants Limited | Real estate | 2010 |
| Andrews Knee Ortho Ltd | Health & social care | 2019 |
| Andrews Local Ltd | Wholesale & retail | 2019 |
| Andy B Limited | Construction | 2018 |
| Anfield Real Estate Limited | Construction | 2023 |
| ANG Care Limited | Other services | 2012 |
| Anglebond Limited | Wholesale & retail | 1998 |
| Anglesit Limited | Wholesale & retail | 2012 |
| Anglex Gems and Jewellery Ltd | Wholesale & retail | 2022 |
| Angloscandic Limited | Administrative & support | 2008 |
| Angus Fraser Limited | Administrative & support | 2003 |
| Anhd International Advisory Services Limited | Administrative & support | 2007 |
| Animatronic Animals Limited | Manufacturing | 2011 |
| Anishi Developments Limited | Real estate | 2001 |
| Anjo Fashion Ltd | Wholesale & retail | 2024 |
| Ankitech Solutions Limited | Information & communication | 2009 |
| Anldn Ltd | Real estate | 2023 |
| ANM Convenience Limited | Wholesale & retail | 2012 |
| Anmol Archive Solutions Limited | Information & communication | 2005 |
| ANN Louise Beauty Ltd | Wholesale & retail | 2018 |
| ANN Louise Bridal Limited | Wholesale & retail | 2015 |
| ANN Louise Butler Limited | Manufacturing | 2018 |
| ANN Louise Events Limited | Administrative & support | 2014 |
| ANN Louise Limited | Wholesale & retail | 2014 |
| ANN Louise London Ltd | Wholesale & retail | 2021 |
| ANN Williams (Embroidery) Limited | Manufacturing | 1964 |
| Anna Ellul Flowers Limited | Wholesale & retail | 2003 |
| Annaluxmy Holdings Ltd | Real estate | 2021 |
| Annaluxmy Ltd | Wholesale & retail | 2011 |
| Annaros Limited | Construction | 1995 |
| Anne Louise Bridal Limited | Wholesale & retail | 2022 |
| Anne Shooter Limited | Administrative & support | 2002 |
| Anneka Rubin Limited | Information & communication | 2020 |
| Annex Services Limited | Health & social care | 2021 |
| Anpri Ventures Ltd | Wholesale & retail | 2025 |
| Anra Residency Ltd | Real estate | 2025 |
| Anro Ltd | Administrative & support | 2015 |
| ANS Fintech Limited | Other services | 2016 |
| Antech Scientific Limited | Administrative & support | 2013 |
| Anteza Ltd | Information & communication | 2016 |
| Anthill Consultancy Ltd | Information & communication | 2022 |
| Anti Gone London Ltd | Other services | 2014 |
| Antilia Arts Limited | Wholesale & retail | 2025 |
| Antitrust Advisory Limited | Wholesale & retail | 2015 |
| Antonni Ltd | Construction | 2025 |
| Antz Kidz Activity Centre Ltd | Education | 2022 |
| Anvaya Investments Limited | Real estate | 2024 |
| Anvaya Limited | Professional & scientific | 2016 |
| Anyanwu Holdings Ltd | Professional & scientific | 2025 |
| AOI Naga Limited | Information & communication | 2013 |
| AP Vishva Ltd | Health & social care | 2023 |
| AP39 Investment Limited | Real estate | 2023 |
| AP39 Limited | Health & social care | 2018 |
| Apdvenice Ltd | Real estate | 2011 |
| Apen Limited | Health & social care | 2020 |
| Apex Global Solutions Ltd | Professional & scientific | 2010 |
| APK Medical Limited | Health & social care | 2016 |
| Aplomb Consulting Limited | Information & communication | 2009 |
| Apodis Media Limited | Information & communication | 2021 |
| Apollo Capital Holdings Limited | Financial services | 2025 |
| Apollonian Limited | Administrative & support | 2017 |
| App Fusion Limited | Information & communication | 2012 |
| Applecross Management Ltd | Real estate | 2025 |
| Applied Automation Solutions Limited | Information & communication | 2012 |
| Approved Rental Ltd | Real estate | 2025 |
| Apps Smiles Limited | Health & social care | 2019 |
| Appsqa Ltd | Wholesale & retail | 2010 |
| Apsl Drainage Ltd | Water & waste | 2023 |
| Apsl Drains Ltd | Manufacturing | 2023 |
| Apsl Invest Ltd | Real estate | 2023 |
| Apsl Japanese Knotweed Ltd | Other services | 2022 |
| Apsl Limited | Manufacturing | 2001 |
| Apsley Lodge Management Limited | Households | 2007 |
| Apsmc Trading Ltd | Financial services | 2021 |
| APSR1 Ltd | Real estate | 2020 |
| Apto Information Technology Limited | Information & communication | 2022 |
| Apworth Ltd | Information & communication | 2026 |
| Aqua Dental Clinic Limited | Health & social care | 2014 |
| Aquira Development Limited | Hospitality | 2017 |