| AGE UK Ealing | Health & social care | 2003 |
| Agile International Ltd | Professional & scientific | 2024 |
| Agilitie Systems Ltd | Information & communication | 2014 |
| AGN Chauffeurs Limited | Transport & logistics | 2025 |
| Agrowin Ltd | Wholesale & retail | 2015 |
| AH ARC Ltd | Wholesale & retail | 2026 |
| AH Metal Work Limited | Construction | 2024 |
| AHF Consulting Ltd | Information & communication | 2025 |
| Ahmed Alkaisy Estates Ltd | Administrative & support | 2018 |
| Ahmed's Group Ltd | Wholesale & retail | 2022 |
| Ahst Vision Limited | Information & communication | 2018 |
| AHT Health Innovation Consultancy Limited | Professional & scientific | 2022 |
| Ahwazi Economic Forum (AEF) | Administrative & support | 2022 |
| AI Structures Limited | Information & communication | 2023 |
| Aiam Limited | Wholesale & retail | 2013 |
| AID for Orphans | Education | 2025 |
| Aiden Properties London Ltd | Real estate | 2025 |
| Aiesia Systems Ltd | Administrative & support | 2020 |
| Aiexg Ltd | Hospitality | 2025 |
| Aimetric Advisory Limited | Professional & scientific | 2025 |
| Aiora Ltd | Hospitality | 2025 |
| Air Vent Compliance Ltd | Administrative & support | 2019 |
| Airconsulteam Media Ltd | Professional & scientific | 2024 |
| Airen Ltd | Wholesale & retail | 2023 |
| Aisha Invest Limited | Real estate | 2019 |
| AIU Building Ltd | Construction | 2022 |
| Aivon Ltd | Manufacturing | 2025 |
| Aiyala Thai Massage Ltd | Other services | 2024 |
| AJ Design Firm Ltd | Professional & scientific | 2024 |
| AJ Project Street Limited | Other services | 2014 |
| AJ Valor Ltd | Wholesale & retail | 2025 |
| AJA Brothers Limited | Construction | 2006 |
| AJD Property Investment Trading Limited | Construction | 2025 |
| AJD Property Investments Limited | Real estate | 2016 |
| AK Construction Solutions Ltd | Construction | 2019 |
| AK Essentials Ltd | Wholesale & retail | 2025 |
| AK Woodworking Ltd | Construction | 2026 |
| AKA Taxi Rentals Limited | Transport & logistics | 2022 |
| AKA Taxis Ltd | Wholesale & retail | 2025 |
| Akaal Construction PVT Ltd | Construction | 2024 |
| Akal Build & Design Ltd | Construction | 2026 |
| Akasa (Europe) Limited | Wholesale & retail | 1997 |
| Akasa Estates Management Limited | Real estate | 2026 |
| AKP Trading Limited | Wholesale & retail | 2022 |
| Akpbuilds Ltd | Construction | 2025 |
| Akshyagamini IT Services & Technologies Ltd | Information & communication | 2011 |
| AL - Shiekh Property Limited | Real estate | 2019 |
| AL Amanah Tours Limited | Wholesale & retail | 2025 |
| AL Falah Shisha Bar Ltd | Wholesale & retail | 2026 |
| AL Hadi Supermarket Ltd | Wholesale & retail | 2023 |
| AL Kahrman Electromechanical Works UK Ltd | Construction | 2021 |
| AL Madina Food Store Ltd | Administrative & support | 2017 |
| AL Noor Halal Meat Limited | Wholesale & retail | 2025 |
| AL Safeer Ltd. | Real estate | 2022 |
| Al-Ahmad Services Limited | Education | 2025 |
| Al-Quresh Ltd | Transport & logistics | 2019 |
| Alador Constructions Ltd | Construction | 2021 |
| Alai Properties Ltd | Real estate | 2024 |
| Alam Automotive Limited | Wholesale & retail | 2024 |
| Aland Management Ltd | Real estate | 2024 |
| Albgas Construction Ltd | Construction | 2011 |
| Albro Windows & Doors Limited | Extraterritorial | 2011 |
| Albro Windows Limited | Manufacturing | 1986 |
| Aldenham Finance Limited | Financial services | 2005 |
| Aldiyar Ltd | Hospitality | 2022 |
| Alenik Group Ltd | Professional & scientific | 2026 |
| Aletheia Strategic Ltd | Professional & scientific | 2026 |
| Alex Prestige Painting and Decorating Ltd | Construction | 2025 |
| Alexis & Hayley (Esher) Limited | Other services | 2016 |
| Alexx Construct Group Ltd | Construction | 2024 |
| ALF Leila WA Leila Ltd | Other services | 2011 |
| Alfaris London Ltd | Transport & logistics | 2021 |
| Algerian Coffee Stores Limited | Wholesale & retail | 1946 |
| Algerian Coffee Supplies Limited | Wholesale & retail | 2000 |
| Alhassani Ltd | Health & social care | 2024 |
| ALI Baba's Ltd | Hospitality | 2020 |
| ALI Management Limited | Wholesale & retail | 2020 |
| Alimar Limited | Real estate | 1962 |
| Alkaisy Group Ltd | Real estate | 2025 |
| Alkebulan Research Ltd | Other services | 2024 |
| Alkhoury & Company Estates Ltd | Real estate | 2023 |
| ALL About AV Audio Visual Ltd | Construction | 2024 |
| ALL About AV Communications Ltd | Information & communication | 2024 |
| ALL About AV Fire Ltd | Administrative & support | 2024 |
| ALL About AV Group Ltd | Financial services | 2024 |
| ALL About AV Satellites & Aerials Ltd | Information & communication | 2024 |
| ALL About AV Security Ltd | Administrative & support | 2024 |
| ALL About AV Smart Home Ltd | Construction | 2024 |
| ALL Quartz & Marble Ltd | Construction | 2021 |
| Alla Engineering Ltd | Professional & scientific | 2017 |
| Allanite Capital (UK) Limited | Financial services | 2021 |
| Allapps Limited | Construction | 2019 |
| Allegro Business Solutions Ltd | Administrative & support | 2014 |
| Allemar Limited | Real estate | 2008 |
| Allende Ltd | Information & communication | 2022 |
| Allgrange Estimating Ltd | Professional & scientific | 2024 |
| Allnick Ltd | Real estate | 2022 |
| Allpoint Management Limited | Households | 2025 |
| Allsorts Building Contractors Ltd | Construction | 2024 |
| Allstimate Ltd | Professional & scientific | 2023 |