| Angelo’S Chef Ltd | Hospitality | 2022 |
| Animal Centred Education Limited | Education | 2018 |
| ANK Engineering Ltd | Construction | 2022 |
| Ankledrive Limited | Households | 1987 |
| ANN Holiday Club Ltd | Hospitality | 2022 |
| Ann-Ari Limited | Real estate | 2024 |
| Annointed Rose UK Ltd | Health & social care | 2013 |
| Anns Holding Limited | Real estate | 2025 |
| ANO IT Solutions Limited | Information & communication | 2009 |
| Ansell Contracts Ltd | Real estate | 2024 |
| Anthony Martin Estate Agents Ltd | Real estate | 2011 |
| ANU Properties Ltd | Real estate | 2021 |
| Anzarache Limited | Hospitality | 2021 |
| Aotd Brands Limited | Manufacturing | 2026 |
| AP Jewellery Company Limited | Extraterritorial | 2013 |
| Apcp Properties Ltd | Real estate | 2025 |
| APD Property Ltd | Real estate | 2018 |
| Apex ABS Limited | Professional & scientific | 2015 |
| Apex Group Properties Ltd | Real estate | 2023 |
| Apex Lift & Escalator Engineers Limited | Construction | 1973 |
| Apex Lift Services Limited | Professional & scientific | 2003 |
| Apex Lifts (Group) Limited | Financial services | 2014 |
| Apex Lifts Limited | Professional & scientific | 1999 |
| Aphex Builders Ltd | Construction | 2007 |
| Apls Electrical Services Ltd | Construction | 2024 |
| Apollo Ductwork Services Limited | Construction | 2013 |
| App 25 Ltd | Transport & logistics | 2025 |
| App Resources Ltd | Information & communication | 2026 |
| Apple's Bakery Limited | Wholesale & retail | 2021 |
| Appoyar Services Limited | Professional & scientific | 2013 |
| Aqua Publishing Ltd | Information & communication | 2012 |
| Aqua-Woda Systems Limited | Construction | 2010 |
| Aquaheat Plumbing UK Limited | Construction | 2012 |
| Aqualogis Europe Ltd | Extraterritorial | 2015 |
| Aqualoop Plumbing Ltd | Construction | 2026 |
| Arabia Clothing Ltd | Wholesale & retail | 2025 |
| Aradhana Consulting Limited | Real estate | 2018 |
| ARB Cafe Ltd | Hospitality | 2025 |
| Arch 4 Management Limited | Administrative & support | 2024 |
| Ardent Interiors Ltd | Construction | 2019 |
| Ardent Property Investments Ltd | Real estate | 2021 |
| Arissa Foods Ltd | Hospitality | 2026 |
| Arjun Infotech Limited | Information & communication | 2021 |
| Arkad Real Estate Ltd | Real estate | 2018 |
| Arks Consultancy Services Limited | Construction | 2009 |
| Arks Investments Management Limited | Real estate | 2018 |
| Arks Services Limited | Construction | 2018 |
| Armed Forces Carpentry Collective CIC | Health & social care | 2026 |
| ARO Accounting Solutions Ltd | Professional & scientific | 2026 |
| Arossurance Ltd | Financial services | 2024 |
| Artisan Food Services Ltd | Wholesale & retail | 2018 |
| Arttech Dental LAB Limited | Manufacturing | 2012 |
| ARW Events Limited | Hospitality | 2020 |
| ASD Cars Limited | Administrative & support | 2025 |
| ASE (AK) Ltd | Wholesale & retail | 2023 |
| ASH Incorporation Limited | Administrative & support | 2018 |
| Ashabol Ltd | Real estate | 2024 |
| Ashfern Limited | Real estate | 1990 |
| Ashi Services Ltd | Information & communication | 2017 |
| Asia Consult Limited | Health & social care | 2023 |
| Asia Foods (Europe) Limited | Wholesale & retail | 2016 |
| ASK Safety and Health Consultancy Limited | Education | 2015 |
| ASL Conseil Ltd | Professional & scientific | 2018 |
| ASL Residences Limited | Real estate | 2023 |
| Aslan Hospitality Limited | Transport & logistics | 2023 |
| Asmj Traders Ltd | Wholesale & retail | 2023 |
| Aspire Accountants (Dartford) Limited | Professional & scientific | 2017 |
| Aspire Healthcare Consulting Ltd | Professional & scientific | 2023 |
| Aspire Homes for Children Ltd | Health & social care | 2025 |
| Aspire Recruitment Consultants Limited | Administrative & support | 2001 |
| ASPIRE2INSPIRE Consultants Ltd | Professional & scientific | 2024 |
| Asrco Solutions Limited | Information & communication | 2026 |
| Asset Building Services Ltd | Construction | 2018 |
| Asset Group Properties Limited | Real estate | 2023 |
| Astral Private Investments Ltd | Real estate | 2019 |
| Asymmetrical Advantage Ltd | Manufacturing | 2023 |
| ATB Associates Ltd | Professional & scientific | 2025 |
| ATB Investments Ltd | Real estate | 2021 |
| ATD Property Solutions Ltd | Hospitality | 2024 |
| Athena Gymnastics Ltd. | Arts & recreation | 2015 |
| Atlantic C Properties Limited | Households | 2017 |
| ATS Car Rentals Limited | Transport & logistics | 2017 |
| ATS Propterties Ltd | Real estate | 2023 |
| Audrey London Atelier Ltd | Manufacturing | 2022 |
| Auracious Ltd | Professional & scientific | 2021 |
| Austen Partners Limited | Administrative & support | 2025 |
| Autolawn Limited | Professional & scientific | 2017 |
| Automated Intelligence Systems Ltd | Information & communication | 2025 |
| AV Roofing and Building Ltd | Construction | 2020 |
| AVA Financial Consultancy PVT Ltd | Professional & scientific | 2016 |
| AVA Flint Ltd | Wholesale & retail | 2024 |
| Avacon Ltd | Wholesale & retail | 2012 |
| Avadootha Enterprise Ltd | Information & communication | 2013 |
| Avalon Diagnostics Ltd | Wholesale & retail | 2020 |
| AVI Shield Tech Ltd | Manufacturing | 2026 |
| Aviation Rhino Limited | Professional & scientific | 2020 |
| Avid Blue Services Ltd | Information & communication | 2016 |
| Avium Education Limited | Education | 2001 |
| Avkalan Ltd | Information & communication | 2023 |
| AW Marketing & Communications Ltd | Professional & scientific | 2025 |