| ALC Construction Ltd | Construction | 2022 |
| Alder & Finch Group Ltd | Extraterritorial | 2026 |
| Aldermaston Power Limited | Energy | 2018 |
| Aldiscarpenting Ltd | Construction | 2025 |
| Aldryx Group Ltd | Extraterritorial | 2026 |
| Ale&Mya Transport Ltd | Transport & logistics | 2020 |
| Alejandra Maria Ltd | Transport & logistics | 2019 |
| Aleksander Market Trading Ltd | Transport & logistics | 2022 |
| Alens Auto Centre Ltd | Wholesale & retail | 2024 |
| Aless Limited | Transport & logistics | 2018 |
| Alessia at Sorelle Ltd | Other services | 2022 |
| Alex Ciocea Limited | Transport & logistics | 2020 |
| Alex Ivan Ltd | Transport & logistics | 2023 |
| Alex James Properties Limited | Real estate | 2017 |
| Alex Manby Limited | Administrative & support | 2025 |
| Alex Partner Ltd | Transport & logistics | 2016 |
| Alex R Delivery Ltd | Transport & logistics | 2025 |
| Alex Transport Limited | Transport & logistics | 2021 |
| ALEXA18 Trans Ltd | Transport & logistics | 2019 |
| Alexander Trader Limited | Professional & scientific | 2017 |
| Alexandra Joinery Ltd | Manufacturing | 2020 |
| Alexandra Nails Ltd | Other services | 2018 |
| Alexandra P Ltd | Transport & logistics | 2026 |
| Alexandra Place (2002 Management) Limited | Households | 2002 |
| Alexandra Place Management Company Limited | Households | 1999 |
| Alexandra's Academy Ltd | Other services | 2021 |
| Alexbrs Ltd | Transport & logistics | 2020 |
| Alexx Courier Ltd | Transport & logistics | 2021 |
| Alfa Events Ltd | Extraterritorial | 2013 |
| Alfa Minicabs Limited | Transport & logistics | 2024 |
| Alfa Specialist Services Limited | Construction | 2023 |
| Alfred Nero Storage Ltd | Transport & logistics | 2024 |
| Alfred Vaughan & Co Limited | Financial services | 2021 |
| Algoray Limited | Wholesale & retail | 2023 |
| Algra Stamrecht Ltd | Financial services | 2008 |
| ALI & HAN Ltd | Real estate | 2024 |
| ALI Supercut Ltd | Other services | 2024 |
| Aliev Global Trade Ltd | Transport & logistics | 2025 |
| Aligen Ltd | Information & communication | 2026 |
| Align Developments Limited | Construction | 2019 |
| Align Electrical Services Limited | Construction | 2024 |
| Align Home Physio Ltd | Other services | 2026 |
| Alin SAS Limited | Transport & logistics | 2024 |
| Aliper Limited | Wholesale & retail | 2023 |
| Alipharm Ltd | Health & social care | 2018 |
| Alive Construction Holdings Ltd | Financial services | 2020 |
| Aljen Limited | Wholesale & retail | 2025 |
| Alkhat Allamea Trading Company Ltd | Wholesale & retail | 2025 |
| ALL About ME Hair Design Ltd | Other services | 2018 |
| ALL Area Installations Ltd | Construction | 2026 |
| ALL Car Service and MOT Centre Limited | Wholesale & retail | 2008 |
| ALL Ears Distribution Limited | Administrative & support | 2008 |
| ALL Education Limited | Education | 2015 |
| ALL in the Folds Ltd | Wholesale & retail | 2022 |
| ALL in Van Couriers Ltd | Transport & logistics | 2022 |
| ALL Nations Living Springs Church | Other services | 2018 |
| ALL Pets at Peace Limited | Other services | 2025 |
| ALL Pro FIX Ltd | Construction | 2020 |
| ALL Round Defence - Risk Management Ltd | Administrative & support | 2022 |
| ALL Round Limited | Wholesale & retail | 2025 |
| ALL Saints Cafe Bar Ltd | Hospitality | 2025 |
| ALL Seasons Roofing Ltd | Construction | 2025 |
| ALL Terrain Inspections Limited | Mining & quarrying | 2011 |
| ALL That Jazz School of Dance & Acro Ltd | Arts & recreation | 2019 |
| ALL Things Christmas Ltd | Wholesale & retail | 2019 |
| ALL Trade Systems Ltd | Construction | 2025 |
| ALL Warm Heating & Plumbing Ltd | Construction | 2019 |
| ALL1PLACE Ltd | Extraterritorial | 2025 |
| Allam Electrical Experts Ltd | Construction | 2026 |
| Allegro Theatre Dance Academy Ltd | Education | 2018 |
| Allen Bennett Controls Limited | Extraterritorial | 2006 |
| Allen Protection Services Ltd | Administrative & support | 2023 |
| Allert Building and Construction Limited | Construction | 2015 |
| Alliance Fluid Handling Limited | Professional & scientific | 2008 |
| Alliance Property Finance Limited | Financial services | 2022 |
| Alliance Tiling Limited | Construction | 2020 |
| Alliance-Group Limited | Manufacturing | 2014 |
| Allied General Insurance Services Limited | Financial services | 1983 |
| Allied Holdings International Ltd | Real estate | 2020 |
| Allied Profiles UK Limited | Wholesale & retail | 2020 |
| Allied RE Group Broker Ltd | Financial services | 2021 |
| Allington Energy Networks Limited | Administrative & support | 2023 |
| Allington O&M Services Limited | Water & waste | 1990 |
| Allington Waste Company Limited | Water & waste | 2003 |
| Allium Homes & Garden Limited | Wholesale & retail | 2016 |
| Allotrope Ltd | Administrative & support | 2015 |
| Allround Machinery Trading Ltd | Wholesale & retail | 2026 |
| Allroundservice Zeeland BV Ltd | Construction | 2024 |
| Allsecure Security Systems Ltd | Administrative & support | 2020 |
| Allsportstuff Limited | Wholesale & retail | 2026 |
| Allstaff Workforce Ltd | Administrative & support | 2023 |
| Alltime Projects Limited | Construction | 2002 |
| Allube Limited | Administrative & support | 2002 |
| Allweighs Weighbridge Services (Hire) Ltd | Other services | 2020 |
| Allweighs Weighing Services Ltd | Other services | 2020 |
| Allworking Ltd | Financial services | 2026 |
| ALM Training Limited | Education | 2020 |
| Alma Driving School LLP | | 2024 |
| Alma Resourcing Ltd | Administrative & support | 2020 |
| Alma Spedition Ltd | Transport & logistics | 2020 |