| APL Joinery (Halifax) Ltd | Construction | 2017 |
| APN Locum Services Limited | Professional & scientific | 2022 |
| Apna Tyres Ltd | Wholesale & retail | 2022 |
| Apollo NOX Ltd | Professional & scientific | 2024 |
| Apollo NOX Properties Ltd | Real estate | 2026 |
| Apollonis Greek Food Ltd | Hospitality | 2025 |
| Appledene Limited | Administrative & support | 1979 |
| Appleyard Lees IP LLP | | 2015 |
| Appleyard Lees Ltd | Administrative & support | 2004 |
| Appliance World (Halifax) Limited | Wholesale & retail | 2016 |
| Apps by MUM Limited | Information & communication | 2011 |
| Apricot Spruce Ltd | Wholesale & retail | 2025 |
| Aprina Limited | Wholesale & retail | 1999 |
| AQ Motors Ltd | Wholesale & retail | 2019 |
| Aqib Waheed Ltd | Wholesale & retail | 2026 |
| Aqua North Ltd | Education | 2024 |
| Aqua Recruiting Ltd | Administrative & support | 2018 |
| Aquajoy Bathlifts Limited | Wholesale & retail | 2002 |
| Aquastone Bathrooms Ltd | Wholesale & retail | 2023 |
| AR Building Management Services Ltd | Construction | 2026 |
| Arabian Treasures Ltd | Wholesale & retail | 2018 |
| Aracari Consulting Limited | Information & communication | 2026 |
| Arachnicraft Ltd | Professional & scientific | 2025 |
| Aramidia Limited | Information & communication | 2020 |
| ARB Consulting Associates Ltd | Professional & scientific | 2012 |
| ARC FM Limited | Administrative & support | 2007 |
| ARC Recruitment (Yorkshire) Limited | Other services | 2004 |
| ARC666 Ltd | Information & communication | 2026 |
| Arca Payments Company Limited | Financial services | 2020 |
| Archibald Mechanical and Property Management Ltd | Construction | 2025 |
| Architect's HQ Limited | Professional & scientific | 2011 |
| Architectural Glass Systems Limited | Construction | 2007 |
| Archmill Property Maintenance Service Limited | Construction | 2021 |
| Archmill Property Management Limited | Real estate | 2022 |
| Arctic Media Limited | Transport & logistics | 1999 |
| Arden Heating Solutions Ltd | Construction | 2023 |
| Area Systems UK Limited | Professional & scientific | 2013 |
| Areera Ltd | Water & waste | 2020 |
| ARK (Halifax) Limited | Administrative & support | 2012 |
| ARK Hoey Properties Ltd | Financial services | 2016 |
| ARK Pallets and Fencing Limited | Manufacturing | 2003 |
| Arke Developments Ltd | Real estate | 2012 |
| Arke Property Holdings (UK) Ltd | Real estate | 2013 |
| Arke Property Investments Limited | Financial services | 2014 |
| Arke SPV 1 Limited | Extraterritorial | 2015 |
| Arkhetechne Ltd | Professional & scientific | 2026 |
| Arkle Windows Ltd | Construction | 2018 |
| Arkoni Holdings Limited | Real estate | 2019 |
| Arkoni Limited | Manufacturing | 1987 |
| Arlo Auto Design Limited | Wholesale & retail | 2023 |
| Armitage Clegg & Co. Limited | Construction | 1966 |
| Armitage Construction Limited | Construction | 2024 |
| Armitage&Bartkiw Ltd | Construction | 2021 |
| Armley Dales Limited | Professional & scientific | 2023 |
| Arncott Training Facility Limited | Arts & recreation | 2024 |
| Aron Kurdish Ltd | Other services | 2025 |
| Arona Health Group Ltd | Health & social care | 2024 |
| Aronstead Limited | Professional & scientific | 1962 |
| Arrans Consulting Limited | Professional & scientific | 2012 |
| Arrow Developments Ltd | Construction | 2020 |
| Art Couture Limited | Wholesale & retail | 2004 |
| Arthurgproperty Ltd | Real estate | 2024 |
| Artisan Adventures Limited | Manufacturing | 2023 |
| Artisan Architecture Ltd | Professional & scientific | 2019 |
| Artisan Servicing Limited | Public administration | 2020 |
| Arts and Crafts SPV Limited | Financial services | 2023 |
| Aryaan Autos Ltd | Wholesale & retail | 2026 |
| AS Clinics Limited | Wholesale & retail | 2023 |
| AS One Childrens Homes Limited | Health & social care | 2025 |
| AS1 Sportswear Ltd | Wholesale & retail | 2025 |
| Asad Khan Medical Services Ltd | Health & social care | 2024 |
| Asadhuzaifawooden Limited | Wholesale & retail | 2025 |
| Asasa Enterprises Ltd | Transport & logistics | 2023 |
| ASB Digital Limited | Professional & scientific | 2008 |
| Asbci | Administrative & support | 2006 |
| Ascend Development and Consulting Ltd | Professional & scientific | 2019 |
| Ascent Computer Services Limited | Information & communication | 1997 |
| Ascnd Activewear Limited | Wholesale & retail | 2025 |
| ASG Digital Ltd | Information & communication | 2026 |
| Asghar Developments Ltd | Real estate | 2026 |
| Asghar Investments Ltd | Real estate | 2024 |
| ASH & T Properties Ltd | Construction | 2024 |
| ASH Education Express Ltd | Education | 2021 |
| ASH Motors Group Ltd | Wholesale & retail | 2025 |
| ASH Tree Education Consultants Limited | Education | 2018 |
| Ashcroft Bishop Ltd | Wholesale & retail | 2025 |
| Ashcroft Management Talent Agency Ltd | Professional & scientific | 1996 |
| Ashday Hall Farm Limited | Energy | 2014 |
| Asher Tech Limited | Professional & scientific | 2018 |
| Ashhh Limited | Professional & scientific | 2024 |
| Ashley Davis Associates Limited | Arts & recreation | 2018 |
| ASI Electrical Contractors Limited | Construction | 2006 |
| Asia Superstore Halifax Ltd | Wholesale & retail | 2021 |
| Asjm Holdings Ltd | Financial services | 2023 |
| Asjm Properties Limited | Real estate | 2017 |
| Asjmellor Ltd | Real estate | 2023 |
| ASK Direct Hire Limited | Financial services | 2008 |
| Aslam & Sons Halifax Limited | Wholesale & retail | 2025 |
| Asmira Bistro Ltd | Hospitality | 2025 |
| Aspen Marketing and Design Limited | Professional & scientific | 2009 |