| Alford Investments Limited | Real estate | 2001 |
| Algarve Sun Limited | Real estate | 2014 |
| Algorithm Limited | Financial services | 2021 |
| ALI Homes Ltd | Real estate | 2017 |
| ALINRN29 Ltd | Transport & logistics | 2019 |
| Alistair Millar Limited | Professional & scientific | 2009 |
| ALL About Modular Limited | Administrative & support | 2013 |
| ALL Comfort Ltd | Construction | 2014 |
| ALL Dent FIX Ltd | Wholesale & retail | 2023 |
| Allen Bros Limited | Agriculture & fishing | 2020 |
| Allen Farms (Coddington) Limited | Agriculture & fishing | 2011 |
| Allerayde SAB Limited | Professional & scientific | 2012 |
| Allied Insulation & Home Improvements Ltd | Construction | 2019 |
| Allure MAY Ltd | Administrative & support | 2017 |
| Allwood & Sons Limited | Real estate | 2023 |
| Allycare Limited | Health & social care | 2017 |
| Alnev Ltd | Manufacturing | 2019 |
| Alpha Agronomy Limited | Agriculture & fishing | 2009 |
| Alpha Properties (East Markham) Ltd | Real estate | 2013 |
| ALS Consultancy and Support Limited | Education | 2015 |
| Alternative Furniture Company Limited | Wholesale & retail | 2002 |
| Alth Trading Limited | Wholesale & retail | 2025 |
| Altrad Global UK Limited | Hospitality | 2022 |
| ALZ Accountancy Limited | Professional & scientific | 2011 |
| AM Scientific Consulting Ltd | Professional & scientific | 2019 |
| AM Surveys Limited | Professional & scientific | 2006 |
| AM2 Architects Ltd | Professional & scientific | 2012 |
| Amazingdens Ltd | Administrative & support | 2024 |
| AMB Engineering and Fabrication Limited | Manufacturing | 2024 |
| AMB Legal Limited | Professional & scientific | 2024 |
| Ambicorp Ltd | Health & social care | 2010 |
| Ambitions Personnel Limited | Administrative & support | 1992 |
| AMC Data Ltd | Information & communication | 2025 |
| AMD Professional Services Ltd | Professional & scientific | 2022 |
| American Candy Newark Ltd | Wholesale & retail | 2024 |
| Amielim Holdings Limited | Real estate | 2021 |
| Ammonite TAP Limited | Real estate | 2021 |
| Ampetronic Limited | Manufacturing | 1987 |
| Ampetronic Solutions Limited | Manufacturing | 2013 |
| AMS (Nottingham) Limited | Administrative & support | 1997 |
| Amteva Holdings Ltd | Real estate | 2019 |
| AMV801 Limited | Administrative & support | 2023 |
| AND Motor Care Limited | Professional & scientific | 2023 |
| AND Motor Company Ltd | Wholesale & retail | 2011 |
| Andeming Limited | Administrative & support | 2017 |
| Andenor Limited | Manufacturing | 2011 |
| Anders Rose Ltd | Construction | 2023 |
| Andion Limited | Professional & scientific | 2001 |
| Andrew Alonzi Limited | Information & communication | 2009 |
| Andrew Borrill Properties Limited | Real estate | 2024 |
| Andrew George Harrison Limited | Transport & logistics | 2004 |
| Andrew Guest (Agricultural Engineers) Limited | Manufacturing | 1999 |
| Andrew Guest Holdings Ltd | Financial services | 2024 |
| Andrew Isaacs Limited | Real estate | 2015 |
| Andrew KAY Farm Holdings Limited | Agriculture & fishing | 2012 |
| Andrew Michael Jewellers Limited | Wholesale & retail | 1999 |
| Andrew Preston Design Ltd | Manufacturing | 2019 |
| Andrew Stewart (Farmers) Limited | Agriculture & fishing | 1987 |
| Andrew Stout Limited | Professional & scientific | 2009 |
| Andrew Ward PT Ltd | Other services | 2006 |
| Andrewcameronassociates Ltd | Professional & scientific | 2018 |
| Andrews Cooling Ltd | Administrative & support | 2012 |
| Andy Beveridge Limited | Wholesale & retail | 2004 |
| Andy Hallam & Co Limited | Construction | 2017 |
| Andy Ralls Consulting Limited | Professional & scientific | 2011 |
| Anele Health and Beauty Ltd | Health & social care | 2019 |
| Angel Steps Limited | Wholesale & retail | 2022 |
| Angells Property Limited | Real estate | 2025 |
| Angells Takeaways Ltd | Wholesale & retail | 2014 |
| ANO Holdings Ltd | Financial services | 2026 |
| Anqa Global, Ltd. | | 2025 |
| Antgriff Limited | Financial services | 2023 |
| Anthony Northcote Planning Limited | Professional & scientific | 2009 |
| AP Batteries Limited | Wholesale & retail | 2011 |
| AP Housing Limited | Real estate | 2020 |
| Ap&S Property Ltd | Real estate | 2025 |
| AP90 Limited | Professional & scientific | 2012 |
| Apex BIM Coordination Ltd | Professional & scientific | 2015 |
| Apex Compliance Solutions Limited | Professional & scientific | 2025 |
| Apex Ideas Ltd | Professional & scientific | 2021 |
| Apex Painting Contractors Ltd | Construction | 2018 |
| Apex Properties Lincoln Ltd | Real estate | 2017 |
| Apium 42 Ltd | Information & communication | 2021 |
| APM GRP Specialists Ltd | Construction | 2021 |
| APM Midlands Ltd | Real estate | 2025 |
| Apollo LAM Limited | Professional & scientific | 2025 |
| Apollo Nano Technology Ltd | Wholesale & retail | 2019 |
| Apollo Systems UK Limited | Manufacturing | 2005 |
| Appfun Limited | Information & communication | 2013 |
| Apple Tree Property Management Holdings Ltd | Real estate | 2019 |
| Apple Tree Property Management Ltd | Real estate | 2019 |
| Applex Management Limited | Wholesale & retail | 2010 |
| Applied Inspiration International Ltd | Education | 2016 |
| Applied Logistics Limited | Transport & logistics | 2022 |
| APT (Design and Build) Ltd | Administrative & support | 2010 |
| Aptus Property Development Limited | Real estate | 2026 |
| ARA Design Limited | Professional & scientific | 2005 |
| ARC Industrial Roofing & Cladding Limited | Construction | 1995 |
| ARC Property and Development Ltd | Real estate | 2022 |
| Arcanum Marketing Ltd | Information & communication | 2025 |