| Allison's Fitness Factory Limited | Arts & recreation | 2009 |
| Alloy Wheel Refurbishment (UK) Ltd | Wholesale & retail | 2011 |
| Alloys UK Wholesale Ltd | Information & communication | 2018 |
| Allpack Packaging Supplies Limited | Manufacturing | 1989 |
| Allsale Goods Ltd | Wholesale & retail | 2016 |
| Allserve Commercial Engineering Ltd | Manufacturing | 2025 |
| Allsys Consulting Ltd | Information & communication | 2011 |
| Allure Laser Clinic (Coventry) Ltd | Other services | 2018 |
| Allweather Guard Roofing &Property Solutions Ltd | Construction | 2025 |
| Ally Taxis Ltd | Transport & logistics | 2026 |
| Ally's Balti House Ltd | Hospitality | 2014 |
| Ally's of Earlsdon Limited | Hospitality | 2025 |
| Allyfazy Healthcare Services Ltd | Health & social care | 2021 |
| Alma Bakery Ltd | Manufacturing | 2025 |
| Alma Bibi Welfare Trust Limited | Other services | 2025 |
| Alma DEL SOL Ltd | Manufacturing | 2020 |
| Alma Ingrid Ltd | Real estate | 2020 |
| Alma Maintenance Ltd | Construction | 2025 |
| Almasar Aldakik Ltd | Wholesale & retail | 2025 |
| Almdon Limited | Wholesale & retail | 2025 |
| Almo Zofy Ltd | Real estate | 2020 |
| Almond Consultancy Limited | Professional & scientific | 2013 |
| Almorah Consulting Ltd | Professional & scientific | 2012 |
| Almtawe Ltd | Wholesale & retail | 2022 |
| Aloe Flower Limited | Wholesale & retail | 2026 |
| Alom KFL Ltd | Real estate | 2024 |
| Alouraluxe Ltd | Wholesale & retail | 2025 |
| Alpa Technology Ltd | Information & communication | 2010 |
| Alpeco Limited | Manufacturing | 1977 |
| Alpha Auto Tech Limited | Wholesale & retail | 2024 |
| Alpha Business Park Limited | Real estate | 2015 |
| Alpha Collectables Ltd | Professional & scientific | 2026 |
| Alpha Constructions Berkshire Limited | Construction | 2025 |
| Alpha Gold Construction Limited | Construction | 2020 |
| Alpha Hedge Limited | Information & communication | 2018 |
| Alpha Install Limited | Manufacturing | 2014 |
| Alpha IT Resourcing Limited | Administrative & support | 2015 |
| Alpha Lasertek Limited | Professional & scientific | 2015 |
| Alpha Music Publishing UK Limited | Information & communication | 2010 |
| Alpha Residential Solutions Ltd | Construction | 2023 |
| Alpha Supermarket Ltd | Wholesale & retail | 2022 |
| Alpha Supported Housing Ltd | Real estate | 2016 |
| Alpha Trowel Ltd | Construction | 2017 |
| Alpha-Manor Ltd | Wholesale & retail | 2025 |
| Alpha-Tek Associates Limited | Information & communication | 1989 |
| ALPHADESIGN1 Ltd | Arts & recreation | 2024 |
| Alphant Brand Management Co., Ltd | Extraterritorial | 2024 |
| Alpina Records Ltd | Information & communication | 2022 |
| Alpine D Ltd | Manufacturing | 2023 |
| Alpine Winter Ltd | Information & communication | 2020 |
| Alqabida Ltd | Wholesale & retail | 2024 |
| ALQAIM55 Ltd | Wholesale & retail | 2022 |
| Alrato Associates Limited | Construction | 2019 |
| Alroboss Limited | Professional & scientific | 2013 |
| ALS Bubble Tea Ltd | Wholesale & retail | 2018 |
| ALS Foods Ltd | Hospitality | 2021 |
| ALS Laboratories (UK) Limited | Professional & scientific | 1989 |
| ALS Life Sciences Limited | Professional & scientific | 2000 |
| ALS Plus Ltd | Transport & logistics | 2025 |
| Alsh P Estate Limited | Real estate | 2026 |
| Alsman Construction Ltd | Construction | 2021 |
| Alstrack Ltd | Construction | 2025 |
| Alta Medica Limited | Health & social care | 2024 |
| Alte Consulting Ltd | Information & communication | 2025 |
| Altechto Limited | Information & communication | 2026 |
| Alternative Estates Property Services Ltd | Administrative & support | 2014 |
| Alternative Estates Sales & Lettings Ltd | Real estate | 2024 |
| Alticare Ltd | Extraterritorial | 2024 |
| Altin Wall and Floor Tiling Ltd | Construction | 2022 |
| Altiore Ltd | Transport & logistics | 2025 |
| Altispex Limited | Information & communication | 2021 |
| Altitude Electrical Contractors Ltd | Construction | 2024 |
| Altmor Building Services Limited | Construction | 1997 |
| Altruhomes Community Interest Company | Households | 2025 |
| Alts Property Limited | Real estate | 2025 |
| Altun Business Limited | Information & communication | 2021 |
| Altura Technologies Ltd | Information & communication | 2026 |
| Alumillion Limited | Manufacturing | 2020 |
| Aluminium Cladding Limited | Manufacturing | 2024 |
| Aluminium Rainwater Goods Limited | Manufacturing | 2024 |
| Alumrock Cake Box Limited | Wholesale & retail | 2018 |
| Alup Transport Ltd | Transport & logistics | 2020 |
| Alva Property Investments Ltd | Real estate | 2021 |
| Alverz Limited | Construction | 2018 |
| Alvine Ltd | Health & social care | 2024 |
| Alvis Robotics Ltd | Manufacturing | 2012 |
| ALW Groundworks and Civils Limited | Construction | 2021 |
| ALW Oakwells Holdings Limited | Financial services | 2025 |
| Alwar (International) Limited | Health & social care | 2012 |
| Always Ltd | Wholesale & retail | 2023 |
| ALY Enterprises Limited | Information & communication | 2018 |
| Alyas Supermarket Limited | Wholesale & retail | 2026 |
| Alyf Accountants Ltd | Extraterritorial | 2021 |
| Alyf Ltd | Professional & scientific | 2021 |
| Alynsons D & Sons Limited | Transport & logistics | 2013 |
| Alzchem UK Limited | Manufacturing | 2022 |
| Alzheimer's & Dementia Products Limited | Wholesale & retail | 2010 |
| AM & PS Properties Ltd | Real estate | 2025 |
| AM Carpentry & Building Services Limited | Construction | 2006 |
| AM Nienaber Consultancy Ltd | Professional & scientific | 2025 |