| Ardour Security Group Ltd | Administrative & support | 2024 |
| Areeya Thai Limited | Hospitality | 2025 |
| Argos International Ltd | Real estate | 2017 |
| ARK & Keirle Construction Limited | Construction | 2019 |
| Arkstone TCG Limited | Wholesale & retail | 2025 |
| Arlow James Developments Ltd | Real estate | 2023 |
| Arlow Plumbing and Heating Ltd | Construction | 2018 |
| Arlow Property Limited | Real estate | 2021 |
| ARM Enterprises Limited | Construction | 2004 |
| Armand Railway Solutions Ltd | Professional & scientific | 2015 |
| Armer Information Management Limited | Information & communication | 1999 |
| Aromany Ltd | Wholesale & retail | 2024 |
| Arrow Tuition Limited | Education | 1995 |
| Art of Africa Ltd | Wholesale & retail | 2013 |
| Artcombe Ltd | Wholesale & retail | 2024 |
| Artedraw Ltd | Wholesale & retail | 2025 |
| Artemis-Uk Solutions Ltd | Administrative & support | 2009 |
| Artigrate Limited | Information & communication | 2018 |
| ASB Livery Limited | Agriculture & fishing | 2012 |
| Ascalon Defence Consultancy Limited | Professional & scientific | 2015 |
| Asens Barber Crew Ltd | Other services | 2018 |
| ASG Services (South West) Limited | Administrative & support | 2018 |
| ASH & Scott Limited | Administrative & support | 2009 |
| ASH Clifford Ltd | Professional & scientific | 2013 |
| Ashcott Car Centre Limited | Wholesale & retail | 2025 |
| Ashcott Private Hire Limited | Transport & logistics | 2024 |
| Ashcott Service Centre Limited | Wholesale & retail | 2025 |
| ASHCOTT50 Ltd | Hospitality | 2025 |
| Ashley Leisure Services Limited | Construction | 2008 |
| Ashmoor Ltd | Real estate | 2023 |
| Ashworth Automotive Ltd | Wholesale & retail | 2017 |
| Aspen Housing and Development Ltd | Real estate | 2016 |
| Aspen Marketing Limited | Professional & scientific | 1994 |
| Aspen Waite (North Devon) Limited | Professional & scientific | 2020 |
| Aspen Waite Business Network Limited | Other services | 2011 |
| Aspen Waite Corporate Finance Limited | Professional & scientific | 2019 |
| Aspen Waite Group Limited | Professional & scientific | 2022 |
| Aspen Waite Innovation Limited | Professional & scientific | 2013 |
| Aspen Waite Kingwell Ltd | Professional & scientific | 2020 |
| Aspen Waite Legacy Limited | Extraterritorial | 2011 |
| Aspen Waite Limited | Professional & scientific | 1999 |
| Aspen Waite Media Limited | Information & communication | 2021 |
| Aspen Waite South East Ltd | Professional & scientific | 2019 |
| Aspen Waite Wholesale Ltd | Wholesale & retail | 2022 |
| Aspire Evolve Ltd | Administrative & support | 2020 |
| Assembly of GOD International Ebenezer Ltd | Other services | 2022 |
| Assiduous Ventures Ltd | Wholesale & retail | 2024 |
| Assured Property Developments Ltd | Real estate | 2025 |
| Astral Tiling Limited | Construction | 2001 |
| ASW Brickwork Ltd | Construction | 2020 |
| ASW Scaffolding Limited | Construction | 2001 |
| ASW Skips Limited | Extraterritorial | 2006 |
| Atelier Consultancy Ltd | Education | 2026 |
| Athelney Builders Ltd | Construction | 2011 |
| Athina Construct Limited | Construction | 2016 |
| Atkinson Holiday Lets Ltd | Hospitality | 2023 |
| Atlas Self Storage Ltd | Administrative & support | 2020 |
| Atomic Beta UK Limited | Professional & scientific | 2021 |
| Audi 4 U Ltd | Wholesale & retail | 2017 |
| AUG Composites Limited | Manufacturing | 2016 |
| Aurora Event Services (UK) Ltd | Professional & scientific | 2019 |
| Aurum Commercial Finance Ltd | Financial services | 2024 |
| Aurum Invoice Finance Ltd | Professional & scientific | 2024 |
| Aurum Property Solutions Ltd | Real estate | 2023 |
| Authentian Limited | Professional & scientific | 2012 |
| Auto-Solve Technology Ltd | Extraterritorial | 2012 |
| Automatic Gear Change Ltd | Wholesale & retail | 2019 |
| Automaxdetails Ltd | Wholesale & retail | 2024 |
| Automend Services Ltd | Wholesale & retail | 2023 |
| Autospray ARC Ltd | Wholesale & retail | 2020 |
| Autospray VSS Limited | Wholesale & retail | 2010 |
| AV Furniture Installations Ltd | Manufacturing | 2024 |
| Avalon Construction Ltd | Construction | 2024 |
| Avalon Digital Solutions Limited | Information & communication | 2017 |
| Avalon Energy Solutions Ltd | Other services | 2018 |
| Avalon Priory Management CLG Ltd | Households | 2026 |
| Avalon Priory Residential CLG Ltd | Households | 2026 |
| Avex Consulting Limited | Information & communication | 2018 |
| Avix Ltd | Transport & logistics | 2025 |
| Avon Reclamation Limited | Wholesale & retail | 2017 |
| Avondale (Bridgwater) Limited | Real estate | 1979 |
| Avonhurst School Limited | Education | 2026 |
| AW Groundworks Limited | Construction | 2021 |
| AW Inspection Services Ltd | Professional & scientific | 2016 |
| Awen Education Consultancy Limited | Education | 2025 |
| AWF Group (Devon) Limited | Extraterritorial | 2013 |
| Awstore Limited | Real estate | 2016 |
| Awty Consulting Limited | Professional & scientific | 2020 |
| AXE Road Body Repair Centre Ltd | Wholesale & retail | 2021 |
| Axeus Capital Limited | Extraterritorial | 2007 |
| Axeus Consulting Limited | Financial services | 2017 |
| Axeus Group Limited | Construction | 2002 |
| Axeus Homes (Filton) LLP | | 2023 |
| Axeus Homes (Highbridge) LLP | | 2023 |
| Axeus Homes (North Petherton) LLP | | 2023 |
| Axeus Homes (Pilton) LLP | | 2023 |
| Axeus Homes (Wells) LLP | | 2023 |
| Axeus Homes Ltd | Construction | 2019 |
| Axeus Lettings Ltd | Real estate | 2020 |
| Axeus Property Development Limited | Construction | 2007 |