| Annyalla Chicks (UK) Broilers Limited | Agriculture & fishing | 2015 |
| Annyalla Chicks (UK) Limited | Agriculture & fishing | 2010 |
| Annyalla Chicks Farms Limited | Other services | 2015 |
| Ansa Care Concept Limited | Health & social care | 2003 |
| Ansatyres Limited | Wholesale & retail | 1994 |
| Ansloos Motors Ltd | Wholesale & retail | 2020 |
| Ansloos Transport Ltd | Transport & logistics | 2023 |
| Antex Transport Services Ltd | Transport & logistics | 2018 |
| AO Property Limited | Real estate | 2025 |
| AO Sublime Ltd | Wholesale & retail | 2010 |
| Aparito Limited | Professional & scientific | 2014 |
| APC Business Ltd | Hospitality | 2023 |
| Apco 1 Limited | Wholesale & retail | 2015 |
| APE Trading Ltd | Education | 2025 |
| Apex Building and Developments Limited | Construction | 2014 |
| Apex Executive Travel Limited | Transport & logistics | 2024 |
| Apex Removals (North West) Limited | Water & waste | 2026 |
| Apex Waste Removals (North West) Limited | Water & waste | 2026 |
| APH Control Limited | Information & communication | 2006 |
| APH Design Limited | Professional & scientific | 2024 |
| APH Signs Limited | Manufacturing | 2010 |
| Apollo LLC Ltd | Wholesale & retail | 2020 |
| Apollo Taxis Wrexham Limited | Extraterritorial | 2016 |
| Apollo Wrexham Limited | Wholesale & retail | 2005 |
| App-Atheia Limited | Information & communication | 2024 |
| Appers Limited | Transport & logistics | 2017 |
| Appointed Safety Ltd | Professional & scientific | 2020 |
| Appropriate Adults UK Limited | Education | 2012 |
| Appsgarages Ltd | Wholesale & retail | 2020 |
| Appsoup Limited | Information & communication | 2020 |
| Apre Marketing Ltd | Administrative & support | 2025 |
| Aqeez Chicken & Pizza Ltd | Hospitality | 2025 |
| Aqua Turris Limited | Real estate | 2023 |
| Aquaden Limited | Other services | 2016 |
| Aquaporin Ltd | Other services | 2025 |
| Aquatec Coatings Limited | Manufacturing | 1999 |
| Aquatic Gardens Limited | Administrative & support | 2023 |
| Aqueduct Hideaway Limited | Hospitality | 2025 |
| AR Procurement Services Ltd | Other services | 2021 |
| Arandce Limited | Health & social care | 2011 |
| Arbteck Limited | Agriculture & fishing | 2020 |
| Arcatlas Ltd | Professional & scientific | 2025 |
| Arcform Limited | Manufacturing | 2003 |
| Archive Joy Ltd | Wholesale & retail | 2022 |
| Archwood Limited | Manufacturing | 1986 |
| Arctic Motion Limited | Financial services | 2018 |
| Ardent PCB Consulting Ltd | Professional & scientific | 2023 |
| Arekp Transport Ltd | Transport & logistics | 2017 |
| ARK Quest Ltd | Construction | 2024 |
| Arkadu Transport Ltd | Transport & logistics | 2020 |
| Arkify Ltd | Professional & scientific | 2021 |
| Armon Limited | Manufacturing | 2002 |
| Armstrong Surveys Ltd | Other services | 2007 |
| Arnoel Limited | Wholesale & retail | 2023 |
| Arran Finance Limited | Financial services | 1997 |
| Array Audio Visual Ltd | Administrative & support | 2019 |
| Arris (UK) Limited | Professional & scientific | 2001 |
| Arrison Limited | Real estate | 2011 |
| Arrowed Investments Limited | Real estate | 2018 |
| Arrowhead HSE Limited | Professional & scientific | 2025 |
| Arrowsmiths NO 1 Limited | Administrative & support | 2018 |
| Art Tracs Limited | Arts & recreation | 2001 |
| Artemis Venue Services Ltd | Administrative & support | 2015 |
| Artisan Conservatories and Windows Limited | Manufacturing | 2005 |
| Artisan Windows Limited | Manufacturing | 2020 |
| Arunan & Co Ltd | Real estate | 2025 |
| Arwel Jones Plumbing & Heating Limited | Construction | 2011 |
| AS ICT Solutions Limited | Information & communication | 2013 |
| ASB Property (UK) Limited | Real estate | 2014 |
| Ascent Utilities Ltd | Construction | 2024 |
| ASG Audio Visual Limited | Professional & scientific | 2024 |
| ASH and Abbey Limited | Real estate | 2015 |
| ASH Manor Cheese Company Limited | Manufacturing | 1989 |
| ASH Manor Holdings Limited | Extraterritorial | 1997 |
| Asha Spice Ltd | Hospitality | 2019 |
| Ashforge Properties Ltd | Real estate | 2024 |
| Ashley Stained Glass Ltd | Construction | 2014 |
| Ashley's Bakery Treats Ltd | Wholesale & retail | 2021 |
| Ashton Hayes Community Energy C.I.C. | Energy | 2011 |
| Ashton-Owen Residential Ltd | Real estate | 2024 |
| ASK MR Jones Electrical Contractors Ltd | Construction | 2017 |
| Askwxm Ltd | Extraterritorial | 2025 |
| Aspec Pvcu Limited | Construction | 2010 |
| Aspect Engineering Consultants Limited | Manufacturing | 1995 |
| Aspirations Dance Ltd | Arts & recreation | 2021 |
| Aspire Ultrasound Consultancy Services Limited | Health & social care | 2017 |
| Asset 360 Ltd | Information & communication | 2023 |
| Associated Assets Ltd | Real estate | 2020 |
| Associated Power Limited | Professional & scientific | 1986 |
| AST Besitzgesellschaft Limited | Professional & scientific | 2013 |
| AST Plastic Containers UK LLP | | 2011 |
| AST Recycling and Reconditioning Limited | Professional & scientific | 2022 |
| Astley & Stratton Ltd | Wholesale & retail | 2023 |
| Astoria Products Limited | Manufacturing | 2014 |
| Astraderm Limited | Health & social care | 2023 |
| Astral Maintenance Limited | Construction | 2008 |
| Astute Management Systems Limited | Professional & scientific | 2019 |
| AT Limited | Administrative & support | 2004 |
| AT Pharma Consulting Limited | Professional & scientific | 2023 |
| Athena Stamps Limited | Wholesale & retail | 2013 |