| AB Group Holdings Ltd | Financial services | 2016 |
| AB Group Trustees Ltd | Administrative & support | 2025 |
| Abbey (Holmethorpe) Limited | Wholesale & retail | 1973 |
| ABC Product Strategy Ltd | Wholesale & retail | 2024 |
| Abelneaux Capital Limited | Professional & scientific | 2011 |
| Abilot Consulting Limited | Information & communication | 2007 |
| Abiskitchen Ltd | Hospitality | 2025 |
| About Roofing Ltd | Professional & scientific | 2009 |
| About Roofing Supplies Limited | Wholesale & retail | 1999 |
| ABS Southern Ltd | | 2006 |
| Absis Limited | Mining & quarrying | 2007 |
| Absolute MA Sutton Ltd | Arts & recreation | 2016 |
| Absolute MA Warlingham Ltd | Arts & recreation | 2021 |
| Absolute Motion Control Ltd | Arts & recreation | 2016 |
| AC Drafting Ltd | Professional & scientific | 2013 |
| Academy Remedial Surveyors Limited | Professional & scientific | 2012 |
| ACB Tools Ltd | Manufacturing | 2026 |
| ACC S1 Limited | Manufacturing | 2006 |
| Accomco (Services) Ltd | Real estate | 2020 |
| Accord Information Solutions Limited | Information & communication | 2009 |
| ACCOUNTING4CONTRACTORS Ltd | Professional & scientific | 2012 |
| Accu Pro Limited | Professional & scientific | 2024 |
| Ace Autolocksmiths Limited | Wholesale & retail | 2019 |
| Ace Partners Ltd | Construction | 2023 |
| ACF UK Logistics Ltd | Transport & logistics | 2025 |
| Achary Eyecare Limited | Wholesale & retail | 2013 |
| ACO Engineering Ltd | Professional & scientific | 2022 |
| Action Broadcast Company Ltd | Information & communication | 2000 |
| Active Investment Consulting Limited | Financial services | 2014 |
| ACTIVE8COMMUNICATIONS Limited | Construction | 2024 |
| Acuity Energy Solutions Limited | Administrative & support | 2017 |
| Acumen Part Time FD Limited | Professional & scientific | 2010 |
| AD Graphics Limited | Manufacturing | 2018 |
| ADA Medical Services Ltd | Health & social care | 2023 |
| Adam Kirby Film and Photography Ltd | Information & communication | 2012 |
| Adama Capital Limited | Professional & scientific | 2024 |
| Adamantsoft Ltd | Information & communication | 2003 |
| Adaptx Advisory Limited | Administrative & support | 2025 |
| Addison Associates Limited | Professional & scientific | 2026 |
| Adenova Ltd | Transport & logistics | 2026 |
| Adey Marketing Ltd | Professional & scientific | 2026 |
| Adhd Treatments Surrey Ltd | Health & social care | 2022 |
| Adiuvo - Management Projects Limited | Construction | 2012 |
| ADL Roofing & Guttering Limited | Construction | 2026 |
| Adorn Care Services Limited | Health & social care | 2020 |
| Adrian Sebastian Martin Ltd | Construction | 2025 |
| Advant International Limited | Information & communication | 2007 |
| Advector Limited | Information & communication | 2012 |
| ADW CC Ltd | Construction | 2024 |
| AED Catering Ltd | Real estate | 2025 |
| AEO Associates Limited | Administrative & support | 2014 |
| Aero Upholstery Services Ltd | Other services | 2019 |
| Aero-Satcom Limited | Information & communication | 2015 |
| Aerodrome Autos Limited | Wholesale & retail | 2017 |
| Aesir Change Consultancy Ltd | Information & communication | 2012 |
| Africonsulting Ltd. | Professional & scientific | 2014 |
| Afro Gate Logistics Ltd | Transport & logistics | 2025 |
| Agen (Environmental) Limited | Administrative & support | 2017 |
| Aghaz Ltd | Hospitality | 2023 |
| Agile Design Consultancy Ltd | Professional & scientific | 2021 |
| Agile Frog Ltd | Information & communication | 2020 |
| Agility Films Ltd | Information & communication | 2019 |
| Agwf Property LLP | | 2007 |
| Ahead Agency UK Limited | Professional & scientific | 2023 |
| Ahead Commercial Limited | Administrative & support | 2012 |
| AI Scheduler Ltd | Professional & scientific | 2024 |
| AI System (Southern) Ltd | Information & communication | 2025 |
| AIM Writing Limited | Arts & recreation | 2016 |
| Aircon Art Ltd | Energy | 2022 |
| Airficiency Ltd | Energy | 2025 |
| Airstead Aviation Ltd | Wholesale & retail | 2026 |
| Airworks Services Ltd | Manufacturing | 1998 |
| AJ Gold Factory Ltd | Manufacturing | 2023 |
| AJ Vince Limited | Professional & scientific | 2022 |
| AJA IT Services Limited | Other services | 2025 |
| AJC Plumbing & Heating Limited | Construction | 2019 |
| Ajcb Consulting Limited | Information & communication | 2018 |
| AJD Initiatives Ltd | Professional & scientific | 2017 |
| AJG Property Ltd | Real estate | 2022 |
| Ajiduah Vocational College Limited | Education | 2025 |
| Akasis Ltd | Information & communication | 2012 |
| AKC Veterinary Ltd | Professional & scientific | 2016 |
| AKS Rentals Limited | Administrative & support | 2020 |
| Aktive Ltd | Construction | 2025 |
| Aktuarial Consulting Ltd | Professional & scientific | 2009 |
| AL Firdaus Development Limited | Construction | 2025 |
| AL the Developer Ltd | Information & communication | 2024 |
| Aladdin Tech Limited | Manufacturing | 2023 |
| Alan Owens Inc Ltd | Information & communication | 2012 |
| Alanic Engineering Limited | Health & social care | 1976 |
| Albbailey Limited | Health & social care | 2022 |
| Albor Ltd | Professional & scientific | 2018 |
| Alderbrook Homes Limited | Construction | 2011 |
| Alessandro Riga Ltd | Administrative & support | 2022 |
| Alexandra Court (Crawley) Management Company Limited | Households | 1989 |
| Alexkat Limited | Real estate | 2009 |
| Alfahamigroups Ltd | Wholesale & retail | 2026 |
| Algabe Ltd | Wholesale & retail | 2023 |
| ALIGN4 (Southern) Ltd | Professional & scientific | 2023 |
| ALL Ingardens Limited | Wholesale & retail | 1994 |