| Aleph Codes Ltd | Information & communication | 2006 |
| Aleph Studio Ltd | Professional & scientific | 2020 |
| Aleph-Ai Ltd | Information & communication | 2025 |
| Aleppo International Ltd | Wholesale & retail | 2023 |
| ALERTGROUP096 Ltd | Administrative & support | 2024 |
| Alesway Limited | Professional & scientific | 1996 |
| Aleurier Ltd | Wholesale & retail | 2022 |
| Alex & Aleks Ltd | Construction | 2016 |
| Alex Bates Consulting Limited | Information & communication | 2004 |
| Alex Burton Design Ltd | Professional & scientific | 2018 |
| Alex Catering Services Ltd | Hospitality | 2023 |
| Alex Cleary Ltd | Wholesale & retail | 2025 |
| Alex GAN Ltd | Transport & logistics | 2025 |
| Alex Goldstein & Associates Property Consultants Ltd | Real estate | 2015 |
| Alex Kenneth Waddell Properties Limited | Real estate | 2019 |
| Alex Keyte Videography Ltd | Information & communication | 2012 |
| Alex Russell Ltd | Manufacturing | 2024 |
| Alexa Group Ltd | Wholesale & retail | 2019 |
| Alexa RAY Trading Limited | Construction | 2026 |
| Alexa&G&M Limited | Transport & logistics | 2018 |
| Alexander Cousins Limited | Professional & scientific | 2019 |
| Alexander Dale Building & Surveying Services Ltd. | Construction | 1995 |
| Alexander Jack Solutions Limited | Professional & scientific | 2021 |
| Alexander James AC Ltd | Financial services | 2021 |
| Alexander James Automotive Ltd | Real estate | 2021 |
| Alexander James RS Ltd | Financial services | 2021 |
| Alexander Jeans Ltd | Wholesale & retail | 2017 |
| Alexander Solicitors Limited | Professional & scientific | 2009 |
| Alexander William Trading Limited | Administrative & support | 2023 |
| Alexanders Catering Ltd | Hospitality | 2020 |
| Alexander’S Events Ltd | Hospitality | 2023 |
| Alexandra Court Residential Home Ltd | Health & social care | 2011 |
| Alexandra Park Limited | Construction | 2021 |
| Alexandra Road II Limited | Real estate | 2016 |
| Alexandre of England 1988 Limited | Extraterritorial | 1987 |
| Alexandru Dorinel Limited | Transport & logistics | 2025 |
| Alexcris Star Ltd | Administrative & support | 2025 |
| Alexes Cleaning Ltd | Administrative & support | 2025 |
| Alexfrz Services Ltd | Other services | 2019 |
| Alexion Limited | Professional & scientific | 2017 |
| Alexis Foko Thanks Ltd | Health & social care | 2020 |
| Alexxcocthebest Limited | Transport & logistics | 2026 |
| ALF Cooke Limited | Manufacturing | 1990 |
| ALF Properties (West Yorkshire) Ltd | Construction | 2012 |
| ALF Property Holdings Limited | Real estate | 2022 |
| Alfa 26 Ltd | Other services | 2026 |
| Alfa Dwellings Limited | Real estate | 2015 |
| Alfa Electrical Limited | Construction | 2014 |
| Alfa Estates (Freehold) Limited | Real estate | 2015 |
| Alfa Evie Ltd | Administrative & support | 2018 |
| Alfa Executive Solutions Ltd | Administrative & support | 2023 |
| Alfa H Portfolio 1 Ltd | Real estate | 2015 |
| Alfa H2 Ltd | Real estate | 2020 |
| Alfa Healthcare Ltd | Hospitality | 2018 |
| Alfa Investments Holding Ltd | Real estate | 2020 |
| Alfa IT Tech Ltd | Information & communication | 2021 |
| Alfa Q8 Ltd | Real estate | 2016 |
| Alfa United Ltd | Administrative & support | 2016 |
| Alfarah Hospital CIC | Public administration | 2025 |
| Alfares (Yorkshire) Ltd | Professional & scientific | 2018 |
| Alfares Limited | Other services | 2015 |
| Alfay Ltd | Administrative & support | 2016 |
| Alfeios Limited | Hospitality | 2026 |
| Alfheim Designs Limited | Professional & scientific | 2018 |
| Alfies Burger & Hotdog Joint Ltd | Hospitality | 2021 |
| Alfies Kitchen Limited | Hospitality | 2019 |
| Alfie’S Healthcare Limited | Health & social care | 2024 |
| Alfonso's Deli Ltd | Hospitality | 2025 |
| Alfred Brown (Woodhead) Limited | Professional & scientific | 1953 |
| Alfred Brown (Worsted Mills) Holdings Limited | Manufacturing | 2025 |
| Alfred Brown(Worsted Mills) Limited | Manufacturing | 1950 |
| Alfred Haley & Co. Limited | Extraterritorial | 1897 |
| Alfredo's Emporium Ltd | Wholesale & retail | 2017 |
| Alfresco Square Pizza Ltd | Hospitality | 2025 |
| ALG Law | Administrative & support | 2010 |
| Algounico Ltd | Wholesale & retail | 2023 |
| ALH Wellness Limited | Arts & recreation | 2024 |
| Alhamdani Consultants Limited | Construction | 1994 |
| Alhamdani Property Ltd. | Administrative & support | 2018 |
| Alhar Consultancy Ltd | Professional & scientific | 2022 |
| ALI & Adam Ltd | Real estate | 2024 |
| ALI & Maya Limited | Hospitality | 2025 |
| ALI Accountants Ltd | Professional & scientific | 2019 |
| ALI and Deniro's Fast Food Ltd | Hospitality | 2024 |
| ALI and DIN Limited | Real estate | 2024 |
| ALI Baba Carpets Leeds Limited | Wholesale & retail | 2017 |
| ALI BEE Ltd | Administrative & support | 2026 |
| ALI Building Constructions Ltd | Construction | 2023 |
| ALI Choudhary & Co Ltd | Professional & scientific | 2026 |
| ALI Financials Leeds Ltd | Information & communication | 2017 |
| ALI Investment Holdings 2 Ltd | Real estate | 2025 |
| ALI Investment Holdings Ltd | Real estate | 2021 |
| ALI Property Investments (Yorkshire) Ltd | Real estate | 2023 |
| ALI Realisations Limited | Administrative & support | 1997 |
| ALI Shop Ltd | Wholesale & retail | 2025 |
| ALI Textiles Global Ltd | Wholesale & retail | 2024 |
| ALI Transfers Ltd | Transport & logistics | 2019 |
| Ali's Fones Ltd | Wholesale & retail | 2024 |
| Ali's Hot Foods Ltd | Hospitality | 2026 |
| Ali's Shawarma and Pizza's Ltd | Hospitality | 2025 |