| AL Recycle Group Ltd | Financial services | 2026 |
| AL Skips Ltd | Water & waste | 2026 |
| Alam TRY Limited | Construction | 2021 |
| Alan H Bailey Limited | Administrative & support | 2014 |
| Alberdor Ltd | Other services | 2018 |
| Albert Road Service Station Limited | Manufacturing | 1985 |
| Albion Construction (Kent) Limited | Construction | 2011 |
| Aldev Fire & Electrical Limited | Construction | 2016 |
| ALE Electrical Ltd | Manufacturing | 2020 |
| Aleali Ayurveda Ltd | Health & social care | 2021 |
| Aleksandar Tanurkov Ltd | Construction | 2018 |
| Alexander E James Ltd | Health & social care | 2024 |
| Alexandor Ltd | Wholesale & retail | 2026 |
| Alfiness Developments Limited | Construction | 2023 |
| Alfiness Real Estates Ltd | Real estate | 2024 |
| Alford Construction Limited | Construction | 1984 |
| ALG Constructions Ltd | Construction | 2015 |
| ALI Raja Properties Limited | Real estate | 2006 |
| Alice Nicholls Limited | Arts & recreation | 2018 |
| Alif Medical Ltd | Health & social care | 2023 |
| Alina & Jamila London Ltd | Wholesale & retail | 2016 |
| Alinea Capital Limited | Financial services | 2018 |
| Alione Mortgages Services Limited | Financial services | 2016 |
| Alis Aquilea Limited | Construction | 2019 |
| Aliwal Imports Limited | Wholesale & retail | 2025 |
| Alkadiri Consultancy Group Ltd | Professional & scientific | 2024 |
| Alkemi Ltd | Wholesale & retail | 2011 |
| Alkosti Limited | Health & social care | 2024 |
| ALL Advertising Ltd | Professional & scientific | 2009 |
| ALL Cisterns Go Ltd | Construction | 2025 |
| ALL Good Pantry LLP | | 2020 |
| ALL Kinds of Blinds (GK) Limited | Wholesale & retail | 2017 |
| ALL Kinds of Blinds (HS) Limited | Construction | 2019 |
| ALL Kinds of Blinds Limited | Financial services | 2017 |
| ALL Media Works Limited | Professional & scientific | 1997 |
| ALL YOU Need Limited | Other services | 2000 |
| All-In Hornchurch Ltd | Wholesale & retail | 2019 |
| Allberry Holdings Limited | Financial services | 2025 |
| Allcare Agency Limited | Health & social care | 2002 |
| Allchimneys London (UK) Limited | Administrative & support | 2016 |
| Alledcue Limited | Information & communication | 2025 |
| Alliance Building & Landscapes Ltd | Construction | 2019 |
| Alliance Knights IT Limited | Information & communication | 2021 |
| Alliance Security Group Ltd | Administrative & support | 2016 |
| Allied Data Resources Limited | Information & communication | 1998 |
| Allied Group International Ltd | Information & communication | 2025 |
| Alll Ltd | Professional & scientific | 2026 |
| Allmides Limited | Health & social care | 2015 |
| Allok Limited | Information & communication | 2025 |
| Allround Fixing Ltd | Construction | 2019 |
| Allsownup Limited | Real estate | 2017 |
| Alluring Nail Bar Limited | Other services | 2012 |
| Allushi Drylining Ltd | Construction | 2023 |
| ALM Uplift Limited | Information & communication | 2018 |
| Alma Beauty Salon Ltd | Other services | 2019 |
| ALO Jobs Limited | Administrative & support | 2023 |
| Alpay Lifts 2006 Ltd | Construction | 2017 |
| Alpha Care Solutions Limited | Administrative & support | 2011 |
| Alpha Page Rankers Limited | Information & communication | 2024 |
| Alpha Realtors Ltd | Real estate | 2023 |
| Alphapine Systems Ltd | Manufacturing | 2023 |
| Alpine Thermal Insulations Ltd | Construction | 2014 |
| Alrope Limited | Other services | 2025 |
| Alta Vision Ltd | Manufacturing | 2022 |
| Altdraw Ltd | Professional & scientific | 2020 |
| Altitude Coffee Ltd | Manufacturing | 2020 |
| ALV Construction Ltd | Construction | 2024 |
| Alva-Elle Construction Limited | Construction | 2017 |
| Alymar Safety Limited | Professional & scientific | 2025 |
| Alysha Nadine Smith Limited | Professional & scientific | 2019 |
| AM Regency Ltd | Real estate | 2026 |
| Am-El Construct Limited | Construction | 2025 |
| AM3D Limited | Professional & scientific | 2016 |
| AMA Express Ltd | Wholesale & retail | 2026 |
| Amaarat Holdings Limited | Real estate | 2020 |
| Amai Consulting Limited | Professional & scientific | 2025 |
| Amaira Investments Ltd | Real estate | 2024 |
| Amalgamation Ltd | Professional & scientific | 2021 |
| Amarnath Consultancy Ltd | Real estate | 2017 |
| Amazing History Enterprises Limited | Information & communication | 2020 |
| Amazon Forest People Ltd | Extraterritorial | 2020 |
| Amazon OIL Ltd | Professional & scientific | 2023 |
| AMB Ecom Limited | Wholesale & retail | 2018 |
| Ambar Investments Limited | Real estate | 2018 |
| Amber Ignis Limited | Public administration | 2026 |
| Ambience Consult Ltd | Information & communication | 2011 |
| AMC Legal Limited | Professional & scientific | 2024 |
| AMC Lift Services Ltd | Manufacturing | 2021 |
| AMC Nursing Limited | Health & social care | 2023 |
| Amelis London Ltd | Other services | 2024 |
| Amerells Limited | Health & social care | 2017 |
| Amey Associates Limited | Professional & scientific | 2010 |
| AMF Films Ltd | Professional & scientific | 2026 |
| AMG Electrical Solutions Limited | Energy | 2012 |
| Amgroud & Co Ltd | Other services | 2025 |
| Amhurst Co Ltd | Professional & scientific | 2019 |
| AMK Crosbie Consultancy Limited | Wholesale & retail | 2015 |
| Amkm Limited | Professional & scientific | 2013 |
| AML Property Services Ltd | Construction | 2014 |
| Amma Joinery Ltd | Manufacturing | 2024 |