| ADI Nica SFX Ltd | Information & communication | 2024 |
| ADM Brickworks Ltd | Construction | 2025 |
| ADM Joinery Ltd | Construction | 2019 |
| Adoo Ltd | Wholesale & retail | 2025 |
| Adpsdistributors Ltd | Wholesale & retail | 2025 |
| ADR Thoroughbreds Ltd | Arts & recreation | 2026 |
| Advance Pinnacle Holding Ltd | Wholesale & retail | 2018 |
| Advance Water Services Limited | Construction | 2018 |
| Advanced Corp Holdings Ltd | Real estate | 2022 |
| Advanced Corp Ltd | Manufacturing | 2019 |
| Advanced Design Services Limited | Professional & scientific | 2020 |
| Advanced Dyeing Solutions Limited | Manufacturing | 2001 |
| Advanced O&G Clinical Services Ltd | Health & social care | 2026 |
| Advanced Technology Assemblies Limited | Manufacturing | 2024 |
| Advanced Technology Cutting Limited | Manufacturing | 2015 |
| Advanced Technology Manufacturing Limited | Financial services | 2015 |
| Aegis Services Holdings Limited | Professional & scientific | 2026 |
| Aegis Services Limited | Professional & scientific | 1989 |
| Aeromotive Sports & Performance Ltd | Wholesale & retail | 2012 |
| AFB Projects Limited | Extraterritorial | 2022 |
| Affinity Residential Property Limited | Construction | 2017 |
| Afia 2 Ltd | Real estate | 2026 |
| Afia Investments Ltd | Administrative & support | 2017 |
| Aftab Travel Limited | Administrative & support | 2022 |
| Agar & ASH Ltd | Manufacturing | 2025 |
| Agas Solution UK Ltd | Wholesale & retail | 2026 |
| AGW Accountants Limited | Professional & scientific | 2026 |
| AH Health Resources Ltd | Health & social care | 2023 |
| Ahanagroup Ltd | Information & communication | 2022 |
| AHJ Medical Ltd | Health & social care | 2014 |
| Ahkp Ltd | Health & social care | 2023 |
| AHM Electronics Ltd | Wholesale & retail | 2023 |
| AHM Logistics Ltd | Transport & logistics | 2023 |
| AHW Health Ltd | Other services | 2019 |
| Aiahab Ltd | Manufacturing | 2023 |
| AID Solution Ltd | Professional & scientific | 2025 |
| AIF Houses Ltd | Real estate | 2025 |
| AIM Community Care Ltd | Administrative & support | 2024 |
| AJ & MK Holdings Limited | Construction | 2015 |
| AJ Foam Ltd | Manufacturing | 2006 |
| AJ Kitchens & Bedrooms Ltd | Wholesale & retail | 2018 |
| AJ Sofa & Beds Ltd | Manufacturing | 2025 |
| AJD Enterprise Limited | Hospitality | 2025 |
| AK & SA (Batley) Ltd | Wholesale & retail | 2025 |
| AK Distributor Ltd | Wholesale & retail | 2025 |
| AK T/A the Three Chefs Ltd | Hospitality | 2024 |
| Akaf Ltd | Education | 2021 |
| Akash by Haji Saab Ltd | Hospitality | 2026 |
| Akbar Holdings Yorkshire Ltd | Financial services | 2025 |
| AKBAR786 Ltd | Transport & logistics | 2025 |
| Akbedstore Limited | Wholesale & retail | 2025 |
| Aksa Auto Electrical Services Ltd | Wholesale & retail | 2019 |
| Akudi Audiology Services Ltd | Health & social care | 2025 |
| Akudi Optical Services Ltd | Health & social care | 2019 |
| Akudi Properties Ltd | Real estate | 2017 |
| AL - Murad (Rochdale) Ltd | Wholesale & retail | 2005 |
| AL - Murad (T.G.) Ltd | Wholesale & retail | 2005 |
| AL Ameen Consulting Limited | Information & communication | 2017 |
| AL Barr Investment Holdings Ltd | Administrative & support | 2025 |
| AL Hafez Limited | Other services | 2000 |
| AL Mubarak Foundation | Information & communication | 2015 |
| AL Sultan Furnishing Ltd | Manufacturing | 2019 |
| Al-Fattah Catering Limited | Hospitality | 2023 |
| Al-Haqq Organisation Ltd | Professional & scientific | 2023 |
| Al-Rizwan Ltd | Other services | 2008 |
| Al-Sultan Consulting Ltd | Professional & scientific | 2023 |
| Alaida Official Ltd | Wholesale & retail | 2024 |
| Alawan Furniture Ltd | Wholesale & retail | 2022 |
| Alayana Ltd | Wholesale & retail | 2023 |
| Alborz Fast Food Ltd | Hospitality | 2019 |
| Alex 24/7 Couriers Ltd | Other services | 2018 |
| Alex Fitting Limited | Construction | 2022 |
| Alexander Duckham & Co.,Limited | Manufacturing | 1920 |
| Alexandra Beds Ltd | Manufacturing | 2019 |
| Alfons Haar Limited | Wholesale & retail | 1995 |
| ALL Brand Cars Ltd | Wholesale & retail | 2025 |
| ALL Furniture Components Ltd | Wholesale & retail | 2024 |
| ALL Kitchens Yorkshire Ltd | Manufacturing | 2024 |
| ALL Stars Sports Cafe Ltd | Hospitality | 2020 |
| Alla Scala Ltd | Hospitality | 2012 |
| Allad Consultancy Services Ltd | Information & communication | 2017 |
| Allad Delivery Services Limited | Transport & logistics | 2026 |
| Allprint Services Ltd | Manufacturing | 2020 |
| Allure DOT Ltd | Hospitality | 2026 |
| Alma Beds Ltd | Manufacturing | 2026 |
| ALP Pharma Limited | Health & social care | 2026 |
| Alpha Components Ltd | Wholesale & retail | 2018 |
| Alpha Gadgets Ltd | Wholesale & retail | 2026 |
| Alpha Network Services Limited | Information & communication | 2000 |
| Alpha Omega Computers Limited | Information & communication | 1999 |
| Alpha Works Ltd | Wholesale & retail | 2025 |
| Alphanumo Ltd | Professional & scientific | 2022 |
| Alpine Accounting Ltd | Professional & scientific | 2020 |
| Alternate Relief Limited | Health & social care | 2024 |
| Alternate Works Limited | Manufacturing | 2026 |
| Aluminium Vehicle Specialists Ltd | Wholesale & retail | 2022 |
| Always Hear Limited | Health & social care | 2021 |
| AM Deen Services Ltd | Professional & scientific | 2025 |
| AM Garden Services Ltd | Administrative & support | 2022 |
| AM Group (Yorkshire) Ltd | Wholesale & retail | 2025 |