| AK70 Holding Limited | Construction | 2020 |
| Akabees Ltd | Real estate | 2021 |
| AKB Investments Ltd | Information & communication | 2015 |
| Akenham Hall Limited | Professional & scientific | 1997 |
| Akenham Properties Ltd | Real estate | 2020 |
| Akkon Shipping (UK) Limited | Transport & logistics | 2022 |
| Aklen Ltd | Information & communication | 2025 |
| Aksent Consultancy Ltd | Information & communication | 2022 |
| Akshar Traders Limited | Wholesale & retail | 2020 |
| Aksoy Property Limited | Real estate | 2012 |
| Aktar & Rahman's Property Ltd | Real estate | 2025 |
| Akunwa Limited | Wholesale & retail | 2024 |
| AL Emaara Ltd | Wholesale & retail | 2025 |
| AL Mubarakk Travel Limited | Administrative & support | 2024 |
| AL Noor Services Ltd | Health & social care | 2026 |
| AL Sohyb Ltd | Other services | 2024 |
| AL Systems Ltd | Construction | 2020 |
| Al-Amin Halal Grocery Limited | Wholesale & retail | 2005 |
| Aladore Ltd | Information & communication | 2023 |
| Alan Mann Properties Ltd | Real estate | 2019 |
| Alan Thompson Energy Consulting Limited | Professional & scientific | 2014 |
| Alana Lucien Ltd | Real estate | 2020 |
| Alaska Developments Limited | Construction | 2016 |
| Albacasa Ltd | Real estate | 2021 |
| Albardan for Trade Ltd | Construction | 2024 |
| Albert Alex Ltd | Transport & logistics | 2022 |
| Albert Consulting Limited | Professional & scientific | 2017 |
| Albert Robex Ltd | Information & communication | 2013 |
| Albion Planning Consultants Limited | Professional & scientific | 2002 |
| Alby Hand Car Wash Ltd | Administrative & support | 2025 |
| ALC Carpentry & Construction Ltd | Construction | 2020 |
| Alcedo International Limited | Professional & scientific | 2023 |
| Alchemy Home Furnishings Ltd | Manufacturing | 2023 |
| Aldar Consulting Ltd | Administrative & support | 2022 |
| Alder Enterprises Ltd | Hospitality | 2024 |
| Alder GS Ltd | Information & communication | 2025 |
| Alder Meadow (Creeting) Management Company Limited | Households | 2022 |
| Aldercroft Ltd | Manufacturing | 2022 |
| Aldertons Accounting Services Limited | Professional & scientific | 2009 |
| Alderwell BBM Ltd | Construction | 2024 |
| Aldous Lamont Limited | Manufacturing | 1998 |
| Aldous Mechanical Ltd | Construction | 2023 |
| Aleksandra Zych Ltd. | Other services | 2013 |
| Alert Search Find Ltd | Information & communication | 2021 |
| Alex Gara Trans Ltd | Transport & logistics | 2021 |
| Alex Hall Engineering Limited | Professional & scientific | 2025 |
| Alex Howard Financial Planning Ltd | Financial services | 2025 |
| Alex Macelaru Ltd | Wholesale & retail | 2024 |
| Alex YEE Limited | Arts & recreation | 2018 |
| Alex&Mada Ltd | Transport & logistics | 2024 |
| Alexander & Co Formations Limited | Administrative & support | 2002 |
| Alexander & Millar Architects Ltd | Construction | 2020 |
| Alexander + Co Nominees Limited | Other services | 2002 |
| Alexander + Co Secretaries Limited | Administrative & support | 2002 |
| Alexander Barclay Business Solutions Ltd | Administrative & support | 2013 |
| Alexander Barclay Limited | Other services | 2000 |
| Alexander Builders Suffolk Ltd | Construction | 2021 |
| Alexander Foxx Limited | Real estate | 2017 |
| Alexander James Carpentry & Building Limited | Construction | 2021 |
| Alexander Matthews Holdings Ltd | Financial services | 2023 |
| Alexander Matthews Investments Limited | Real estate | 2022 |
| Alexander Matthews Property Limited | Real estate | 2020 |
| Alexander Whitley Dance Company | Arts & recreation | 2013 |
| Alexandra Asset Limited | Hospitality | 2016 |
| Alexandra Hotel Management Limited | Hospitality | 2016 |
| Alexandrite Risk Consulting Limited | Professional & scientific | 2025 |
| Alexduta Ltd | Transport & logistics | 2024 |
| Alex’S Family Ltd | Manufacturing | 2026 |
| ALF Freight Ltd | Transport & logistics | 2026 |
| ALF Solutions Ltd | Wholesale & retail | 2024 |
| Alfa Bella Foods Ltd | Wholesale & retail | 2007 |
| Alfa-European Investments Corporation Limited | Extraterritorial | 2001 |
| Alfaizh Solutions Ltd | Administrative & support | 2025 |
| Alfern Consulting Ltd | Administrative & support | 2022 |
| Alfie Property Maintenance Ltd | Construction | 2025 |
| Algar Consulting Ltd | Information & communication | 2024 |
| ALH Consultancy Limited | Information & communication | 2024 |
| ALI Haulage Ltd | Transport & logistics | 2023 |
| ALI Vision Limited | Health & social care | 2020 |
| Ali's Auto Solutions Limited | Wholesale & retail | 2023 |
| Alia Way (North Lopham) Management Company Limited | Households | 2023 |
| Alianza Logistics UK Ltd | Transport & logistics | 2025 |
| Alianza Property Management and Consultancy Ltd | Real estate | 2012 |
| Alias Contractor Limited | Construction | 2020 |
| Alicardiff Ltd | Wholesale & retail | 2025 |
| Alice Pescott Frost Events Limited | Arts & recreation | 2024 |
| Align Strategy Limited | Professional & scientific | 2013 |
| Alina&Care Service Limited | Public administration | 2024 |
| Alinnitu Ltd | Transport & logistics | 2026 |
| Alinsub Care Limited | Health & social care | 2022 |
| Alin’S Trasport’S Ltd Limited | Transport & logistics | 2025 |
| Aliskevicius Ltd | Transport & logistics | 2018 |
| Alistair Brownlee Ltd | Arts & recreation | 2009 |
| Alistair Millar Design Engineering Limited | Administrative & support | 1981 |
| Alistair Smith Building Services Limited | Construction | 2007 |
| Alistair Taylor Associates Limited | Information & communication | 2017 |
| Alive Technology Limited | Information & communication | 2003 |
| ALK Tech Limited | Wholesale & retail | 2025 |
| Alkaia Ltd | Transport & logistics | 2020 |
| Alkhaki Limited | Wholesale & retail | 2025 |