| Airtec Pneumatics UK Limited | Manufacturing | 2001 |
| Aisha Entertainment Ltd | Arts & recreation | 2026 |
| Aisla's Crafty Creations Ltd | Wholesale & retail | 2024 |
| Aisling Sheedy Ltd | Financial services | 2022 |
| Aitil Networks Ltd | Information & communication | 2025 |
| Aitken & Daughters Limited | Hospitality | 2019 |
| Aiza Nazir Ltd | Health & social care | 2024 |
| AJ Homes and Designs Ltd | Construction | 2026 |
| AJ Murray Ltd | Professional & scientific | 2024 |
| AJ Richardson Flooring Limited | Construction | 2026 |
| AJ Richardson Properties Limited | Real estate | 2026 |
| AJ Roadworks Limited | Construction | 2025 |
| AJA Site Services Ltd | Transport & logistics | 2025 |
| Ajax Construction Services Limited | Construction | 2024 |
| Ajay (York) Limited | Construction | 2016 |
| Ajay Rajeev Ltd | Professional & scientific | 2025 |
| AJB Highway Fencing Ltd | Construction | 2024 |
| AJB Logic Ltd | Information & communication | 2025 |
| AJC Solutions Ltd | Other services | 2014 |
| AJD Engineering Services Ltd | Professional & scientific | 2016 |
| Ajdo Developments Limited | Real estate | 2018 |
| Ajdo Holdings LLP | | 2023 |
| Ajdo Property Limited | Real estate | 2016 |
| Ajdo Residential Developments Limited | Construction | 2024 |
| Ajdw Engineering Limited | Professional & scientific | 2015 |
| AJE Solar Ltd | Construction | 2023 |
| AJH Homes Limited | Real estate | 2019 |
| Ajidans Studios Productions Ltd | Education | 2026 |
| AJK Improvements Limited | Construction | 2014 |
| AJK Lettings and Building Services Ltd | Real estate | 2020 |
| AJK Valeting Services Limited | Wholesale & retail | 2025 |
| Ajmal Investment Properties Limited | Real estate | 2025 |
| Ajmc Group Ltd | Construction | 2026 |
| Ajmr Investments Limited | Real estate | 2024 |
| AJN Forensic Psychology Services Ltd | Health & social care | 2024 |
| AJN Framing Ltd | Construction | 2024 |
| AJO Enterprise Ltd | Administrative & support | 2017 |
| AJP Holdings (Doncaster) Limited | Financial services | 2023 |
| AJP Home Improvements Limited | Construction | 2008 |
| AJS @ One Stop Car Care Centre Ltd | Wholesale & retail | 2026 |
| AJS Media Limited | Professional & scientific | 2026 |
| AJS Recovery & Removals Limited | Transport & logistics | 2025 |
| AJS Security Doncaster Ltd | Administrative & support | 2026 |
| AJT Surveys Limited | Administrative & support | 2003 |
| AJV Garden Services Ltd | Administrative & support | 2023 |
| Ajvan Investments Ltd | Construction | 2023 |
| AJW Farm Machinery Limited | Manufacturing | 2023 |
| AK & AV Properties Ltd | Real estate | 2025 |
| AK Glass & Glazing Limited | Construction | 2001 |
| AK Medical Enterprises Ltd | Wholesale & retail | 2013 |
| AK Phones and Accessories (Doncaster) Ltd | Wholesale & retail | 2022 |
| AK Phones Doncaster Ltd | Wholesale & retail | 2023 |
| AK Pubs & Bars Ltd | Hospitality | 2020 |
| AK Scunthorpe Limited | Arts & recreation | 2026 |
| AK786 Properties Ltd | Real estate | 2023 |
| AK786CABS Limited | Transport & logistics | 2021 |
| AKA Barbers Ltd | Other services | 2026 |
| AKA Pre-Cast Management Services Limited | Construction | 2008 |
| Akdemir Bookkeeping Ltd | Professional & scientific | 2024 |
| Akeferry Ltd | Real estate | 2024 |
| Akhyl D.L.P Ltd | Transport & logistics | 2024 |
| Akpk Properties Limited | Real estate | 2025 |
| Aksahin Estate Limited | Real estate | 2025 |
| AL AYN Group Limited | Other services | 2025 |
| AL FM HR Ltd | Construction | 2025 |
| AL Logistics Group Limited | Transport & logistics | 2018 |
| AL Mushtaqeen for Wholesale and Retail Trade Ltd | Extraterritorial | 2026 |
| AL Nour Retail Limited | Wholesale & retail | 2025 |
| AL Professional Services Limited | Financial services | 2012 |
| AL Suhool AL Muzdahira AL Jadeeda for Investment Ltd | Financial services | 2025 |
| Al-Baraseen for Contracting and General Trading Ltd | Financial services | 2025 |
| Al-Basha Lounge Ltd | Hospitality | 2024 |
| Al-Madaan for General Trading Ltd | Wholesale & retail | 2025 |
| Al-Mahdi Real Estate Limited | Real estate | 2025 |
| Al-Marsad Al-Makani Engineering Consultancy Ltd | Professional & scientific | 2016 |
| AL3X Garage Limited | Wholesale & retail | 2023 |
| Aladinma CIC | Professional & scientific | 2025 |
| Alakasam Ltd | Arts & recreation | 2018 |
| Alan Bennett Racing Ltd | Arts & recreation | 2001 |
| Alan T Morrall Ltd | Public administration | 2022 |
| Alana Rail Ltd | Professional & scientific | 2024 |
| Alany Barbers Ltd | Other services | 2021 |
| Alazrak 2 Engineering Consultancy Ltd | Professional & scientific | 2014 |
| ALB Delivery Ltd | Transport & logistics | 2024 |
| Albaqa Services Limited | Households | 2009 |
| Albemarle Holdings Limited | Financial services | 2017 |
| Albemarle Homes Limited | Real estate | 2013 |
| Albemarle Portfolio Limited | Real estate | 2013 |
| Albert & Co Property Management Limited | Real estate | 2016 |
| Albert 2019 Ltd | Transport & logistics | 2019 |
| Albert's DEN Ltd | Manufacturing | 2022 |
| Albinel Ltd | Transport & logistics | 2017 |
| Albion Castle Estates Ltd | Real estate | 2019 |
| Albion Financial Advice Services Ltd | Financial services | 2016 |
| Albion Place Limited | Households | 1996 |
| Albion Strategic Holdings Ltd | Construction | 2026 |
| Albion Transmission Limited | Wholesale & retail | 1980 |
| Albrix Limited | Wholesale & retail | 2023 |
| Albt Property Ltd | Real estate | 2019 |
| Albu Processing Ltd | Administrative & support | 2024 |