| Alan Bush Driver Training Limited | Education | 2003 |
| Alan Electrical Holdings Limited | Professional & scientific | 2014 |
| Alan Electrical Limited | Manufacturing | 1971 |
| Alan Electrical Switchgear Holdings Limited | Professional & scientific | 2021 |
| Alan Hewitt Consulting Services Ltd | Professional & scientific | 2017 |
| Alan Murray Prodrive Ltd | Professional & scientific | 2025 |
| Alana Marketing Ltd | Professional & scientific | 2002 |
| Alarakhia Psychological Wellbeing Ltd | Health & social care | 2026 |
| Alban Engineering Consultants Limited | Professional & scientific | 2004 |
| Alban Suites Ltd | Households | 2026 |
| Albany Court Freeholders Limited | Real estate | 2006 |
| Albany Mews Management Company Limited | Households | 1984 |
| Albastone Projects Limited | Construction | 2013 |
| Albatros Productions Limited | Arts & recreation | 1985 |
| Alberson Ltd | Construction | 2022 |
| Albert RD Ltd | Real estate | 2025 |
| Albert Wheels Refurbished Limited | Administrative & support | 2025 |
| Alberto Pavanello Limited | Wholesale & retail | 2013 |
| Albion Impex Supply Ltd | Wholesale & retail | 2024 |
| Albion Service Centre Ltd | Wholesale & retail | 2019 |
| Alboski Limited | Professional & scientific | 2012 |
| Albrazesh Holdings Limited | Financial services | 2025 |
| Albrich Consult Limited | Professional & scientific | 2024 |
| Albricor Ltd | Manufacturing | 2019 |
| Albury Motor Company Limited | Wholesale & retail | 2014 |
| Albury Wellbeing Ltd | Health & social care | 2020 |
| ALC Consultancy Services Ltd | Administrative & support | 2024 |
| ALC Speech Therapy Limited | Health & social care | 2021 |
| Alcalay Limited | Wholesale & retail | 1999 |
| Alcova Asset Management LLP | | 2011 |
| Aldea Creatives Limited | Professional & scientific | 2026 |
| Aldenham Property Limited | Other services | 2002 |
| ALE Opportunity Ltd | Construction | 2016 |
| Alea Risk Limited | Financial services | 2015 |
| Alenzacandles Ltd | Manufacturing | 2025 |
| Alessia Contracting Ltd | Transport & logistics | 2020 |
| Alete Ltd | Information & communication | 2012 |
| Alex Deco Design Limited | Construction | 2015 |
| Alex Simpson Film Ltd | Information & communication | 2018 |
| ALEX2 Ltd | Other services | 2019 |
| Alexander & Harvey Property Ltd | Real estate | 2022 |
| Alexander Adderson Ebbsfleet Limited | Financial services | 2025 |
| Alexander Bottom Limited | Professional & scientific | 2013 |
| Alexander Express Limited | Hospitality | 2024 |
| Alexander Imaging Limited | Arts & recreation | 2012 |
| Alexander Saunders Limited | Professional & scientific | 2019 |
| Alexandra Holdings Limited | Real estate | 2015 |
| Alexandra House Properties Limited | Construction | 2020 |
| Alexia BA Consulting Ltd | Professional & scientific | 2018 |
| Alexite Properties Ltd | Real estate | 2026 |
| Alextronic Limited | Wholesale & retail | 2015 |
| Alfa F&B Ltd | Hospitality | 2023 |
| Alfa Propserv Ltd | Real estate | 2025 |
| Alfa Propvest Ltd | Real estate | 2025 |
| Alfaxtransport Ltd | Wholesale & retail | 2025 |
| Alfaxtremetransport Ltd | Wholesale & retail | 2025 |
| Alfimar Motors Ltd | Wholesale & retail | 2014 |
| Alfra Jewellery Ltd | Wholesale & retail | 2022 |
| ALG Procon Services Ltd. | Professional & scientific | 2017 |
| Alhafiz Traders Limited | Wholesale & retail | 2018 |
| ALI Q ENT Ltd | Health & social care | 2020 |
| ALI Raza Motors Ltd | Wholesale & retail | 2019 |
| Ali-Abdul-Ali Motors Limited | Wholesale & retail | 2025 |
| Aliance Sports Ltd | Arts & recreation | 2022 |
| Aliata Limited | Financial services | 2015 |
| Alicecleaningone Ltd | Administrative & support | 2025 |
| Alif Creations Ltd | Information & communication | 2022 |
| Alignedworks Ltd | Professional & scientific | 2026 |
| Alimarns Ltd | Professional & scientific | 2012 |
| Alin Pirvu Company Ltd | Construction | 2019 |
| Alinda Accounting Ltd | Professional & scientific | 2024 |
| Alisha Care Ltd | Health & social care | 2019 |
| Alison Ford Consulting Ltd | Administrative & support | 2021 |
| Alison Pirfo Consulting Ltd | Professional & scientific | 2014 |
| Alive and Earthed Electrical Limited | Construction | 2019 |
| Aliyan Dream Property PVT Ltd | Real estate | 2024 |
| Aliz Fashions Ltd | Wholesale & retail | 2023 |
| Aliza Home Decor Ltd | Wholesale & retail | 2019 |
| Aliza Ltd | Wholesale & retail | 2023 |
| ALK Associates Ltd | Information & communication | 2015 |
| Alkyl Chemicals Ltd | Wholesale & retail | 2022 |
| ALL About Educate (UK) Ltd | Education | 2013 |
| ALL About Houses Ltd | Real estate | 2024 |
| ALL About Property Limited | Administrative & support | 2018 |
| ALL Centre Limited | Information & communication | 2023 |
| ALL Children's Services Ltd | Health & social care | 2024 |
| ALL Clear Waste Limited | Water & waste | 2018 |
| ALL Day Recruitment Limited | Administrative & support | 2002 |
| ALL Fired UP Digital Ltd | Information & communication | 2024 |
| ALL Joy Care Services Ltd | Professional & scientific | 2025 |
| ALL Perfect Co Limited | Construction | 2009 |
| ALL Perfect Seasons Ltd | Wholesale & retail | 2026 |
| ALL Systems Electrical Limited | Construction | 2024 |
| ALL the More Group Ltd | Professional & scientific | 2024 |
| ALL Things Greek Limited | Manufacturing | 2018 |
| ALL Vape Limited | Manufacturing | 2017 |
| ALL Wired UP Solutions Ltd | Construction | 2022 |
| Allan Consulting Limited | Administrative & support | 2017 |
| Allan Wright Construction Ltd | Construction | 2016 |
| Allbrook House Limited | Households | 2018 |