| 032 Design Limited | Professional & scientific | 2001 |
| 10 Consulting Services Limited | Information & communication | 2007 |
| 1NE Project Solution Limited | Professional & scientific | 2006 |
| 1ST Rate Products (Midlands) Ltd | Wholesale & retail | 2004 |
| 20/20 Icare Ltd | Wholesale & retail | 2020 |
| 34 South Limited | Health & social care | 2006 |
| 36 Avenue Road Limited | Administrative & support | 2005 |
| 3N2 Ltd | Extraterritorial | 2011 |
| 4G Holdings Limited | Real estate | 1980 |
| 852 Superstore Ltd | Wholesale & retail | 2023 |
| A & I Events (EOT) Trustee Limited | Administrative & support | 2024 |
| A D Site Welding Services Ltd | Administrative & support | 2010 |
| A Holmes (Butchers) Limited | Wholesale & retail | 2003 |
| A M Charles Construction Ltd | Construction | 2019 |
| A M Universal Limited | Wholesale & retail | 2006 |
| A P B S Ltd | Professional & scientific | 2003 |
| A Potterton Limited | Real estate | 1923 |
| A. K. Impex Limited | Wholesale & retail | 2004 |
| A. Townsend Promotions Limited | | 1979 |
| A.A. Brown Engineering Ltd | Manufacturing | 1961 |
| A.B.C. Danoto Limited | Real estate | 1994 |
| A.J. Dalby Ltd | Construction | 2006 |
| A.R. Folland &Co. Limited | Construction | 1956 |
| A.T.L. Hydraulics Limited | Wholesale & retail | 2000 |
| A.W. Technology Limited | Manufacturing | 1990 |
| A1 Binding & Trimmings Ltd | Manufacturing | 2007 |
| A1 Staff LLP | | 2013 |
| A1 Wedding Services Ltd | Other services | 2006 |
| Aardvark Designs Limited | Professional & scientific | 2006 |
| Aaxll Brands Company Limited | Health & social care | 2019 |
| ABO Partners Limited | Professional & scientific | 2003 |
| AC & M Services Ltd | | 2004 |
| Academia Press Ltd. | Information & communication | 1994 |
| Access 2 Access Limited | Extraterritorial | 2006 |
| Accountancy & Investment Management Services Limited | Professional & scientific | 2004 |
| Accounting for Growth Limited | Administrative & support | 2002 |
| Ackerley Investments Limited | Real estate | 2000 |
| Acorns Events Limited | Arts & recreation | 2007 |
| Acothane Coatings Ltd | Wholesale & retail | 2025 |
| Action Vehicle Sales (Midlands) Limited | | 1979 |
| Actons Limited | Extraterritorial | 1995 |
| AD London HR Consultancy Ltd | Professional & scientific | 2025 |
| Adam Halliday Decorators Limited | Construction | 2002 |
| Adams & Jones Limited | Real estate | 2006 |
| Adder Ltd | Manufacturing | 2003 |
| Adfil Limited | Wholesale & retail | 1996 |
| Adhar Project | Health & social care | 2005 |
| Adhg Ltd | Real estate | 2021 |
| Admiral Forwarding Limited | Transport & logistics | 1991 |
| Adrian Young Limited | Administrative & support | 2007 |
| Advanced Bolting Solutions Limited | Manufacturing | 2002 |
| Advanced Carbide Tooling Limited | Manufacturing | 1984 |
| Advanced Smartbuild Ventures Ltd | Real estate | 2003 |
| Advent Books Limited | Information & communication | 2003 |
| AEC Marketing Limited | Professional & scientific | 2005 |
| Affiliation of Rotational Moulding Organisations Ltd | Other services | 2013 |
| Affinity Wraps Limited | Administrative & support | 2025 |
| African Energy Reformation Ltd | Professional & scientific | 2024 |
| Aghoco 1762 Limited | Financial services | 2018 |
| Agnes Foods International Ltd | Information & communication | 2021 |
| Ahct Group Limited | Wholesale & retail | 2020 |
| Airlie Geomatics Ltd | Professional & scientific | 2007 |
| Airlines Global Solutions Limited | Other services | 2020 |
| Ajwgk Limited | Financial services | 2019 |
| Ajwgsw Limited | Extraterritorial | 2019 |
| Akira Foods Ltd | Wholesale & retail | 2024 |
| AL Kawthar Productions Ltd | Administrative & support | 2004 |
| Alacritas Consultancy Limited | Professional & scientific | 2002 |
| Alan Hirst & SON Limited | Construction | 2003 |
| Alan Jerham Transport Ltd | Transport & logistics | 2006 |
| Alden Electrical Limited | Construction | 2007 |
| Alexander (Motor Services) Limited | Wholesale & retail | 2004 |
| Alexandrou Consultancy Limited | Professional & scientific | 2024 |
| Alfa Tams Holdings Ltd | Real estate | 2021 |
| Alfred Willday & SON Limited | Information & communication | 1945 |
| Algarvilla.Co.Uk Limited | Real estate | 2005 |
| Alistair Nicoll Limited | Construction | 2002 |
| ALL Hire (Sales) Limited | Administrative & support | 1990 |
| Allured and Taylor | | 1998 |
| Alphalex Limited | Wholesale & retail | 1975 |
| AM System Limited | Manufacturing | 2003 |
| Amalan Convenience Store Ltd | Wholesale & retail | 2020 |
| Amalgamated Marketing Services Limited | Transport & logistics | 1993 |
| Amberbray Limited | Real estate | 1996 |
| Amigos Pizza (Oakham) Ltd. | Hospitality | 2004 |
| Amiko Home Ltd | Wholesale & retail | 2019 |
| Amit Odedra Limited | Wholesale & retail | 2007 |
| AMS Hand Car Wash Limited | Wholesale & retail | 2014 |
| AN Medics UK Ltd | Health & social care | 2023 |
| Anchor Exhibitions and Electrical Services Limited | Construction | 2005 |
| Anderton Concrete Products Limited | Manufacturing | 1985 |
| Anditec Limited | Information & communication | 1995 |
| Andy Taylor Welding Limited | Manufacturing | 2007 |
| Angelo 2001 Ltd | Transport & logistics | 2019 |
| Anglo African Ventures Ltd | Wholesale & retail | 2005 |
| Ansaar | Health & social care | 2006 |
| Antalya Mezze BBQ Ltd | Hospitality | 2022 |
| AOK Investments Limited | Real estate | 2000 |
| Apac Group Limited | Wholesale & retail | 2000 |
| Apent Limited | Professional & scientific | 2020 |