| Apple County Design Ltd | Real estate | 2014 |
| Apple FM C.I.C. | Information & communication | 2011 |
| Applebees Fitness Ltd | Arts & recreation | 2019 |
| Applewood Carpentry & Joinery Ltd | Construction | 2014 |
| Applewood Holdings Limited | Real estate | 2015 |
| Appleyard (Somerset) Limited | Construction | 2018 |
| APR Law Limited | Professional & scientific | 2016 |
| Apteryx Limited | Professional & scientific | 2021 |
| Aqua Santa Medical Services Ltd | Transport & logistics | 2025 |
| Aquafolium Ltd | Health & social care | 2017 |
| Aquagarden Interpet Ltd | Manufacturing | 2025 |
| Aquamarine Medicals Limited | Health & social care | 2020 |
| AR Construction Services (UK) Ltd | Construction | 2015 |
| AR Driveways Ltd | Construction | 2020 |
| AR Holiday Properties Limited | Hospitality | 2016 |
| Arazu Consulting Limited | Hospitality | 2012 |
| ARB Resolutions Limited | Agriculture & fishing | 2021 |
| Arbcology Ltd | Agriculture & fishing | 2025 |
| Arbortech Professional Tree Services Ltd | Extraterritorial | 1999 |
| ARC Asbestos Removal & Surveys Ltd | Water & waste | 2023 |
| ARC Plumbing and Heating South West Ltd | Construction | 2019 |
| ARC Production Services Ltd | Information & communication | 2015 |
| ARC Property Taunton Limited | Real estate | 2008 |
| ARC Taunton Limited | Construction | 2004 |
| Arch (Lincolnshire) Ltd | Information & communication | 2025 |
| Architectural Thread Ltd | Professional & scientific | 2012 |
| Archstone Limited | Wholesale & retail | 2000 |
| Arctic Engineering Solutions Ltd | Construction | 2023 |
| Arctic Group SW Limited | Construction | 2025 |
| Arctura Holding Ltd. | Other services | 2009 |
| Arctura Ltd. | Other services | 2009 |
| Arctypes Limited | Administrative & support | 2026 |
| Arditti Carpets Limited | Wholesale & retail | 1998 |
| Ardo Medical Limited | Manufacturing | 2005 |
| Ardux Ltd | Information & communication | 2019 |
| Areli Developments Limited | Professional & scientific | 2020 |
| Areli Group Limited | Financial services | 2025 |
| Arena Sound and Vision Limited | Arts & recreation | 2006 |
| Arete Sports Rehabilitation Ltd | Other services | 2025 |
| Arff Ltd | Real estate | 1997 |
| Aries Limited | Administrative & support | 1987 |
| Arigna Developments Ltd | Real estate | 2013 |
| Arixx Visuals Ltd | Professional & scientific | 2021 |
| ARK Removals & Storage Limited | Transport & logistics | 2008 |
| Arley Properties Limited | Professional & scientific | 1929 |
| Armco (South West) LLP | | 2017 |
| Armstrong France Holdings Limited | Financial services | 2011 |
| Armstrong Veterinary Services Ltd | Professional & scientific | 2009 |
| Arnold Commercial Finance Limited | Financial services | 1990 |
| Arnold Properties ( South West ) Limited | Real estate | 2018 |
| Arnold Ramos Ltd | Construction | 2025 |
| Aroma Ice Taunton Limited | Wholesale & retail | 2002 |
| Arpj Limited | Real estate | 2016 |
| Arrowplace Limited | Real estate | 2001 |
| ARS Beheer Limited | Financial services | 2026 |
| Art Home Care Limited | Real estate | 1977 |
| Artisaz Limited | Arts & recreation | 2022 |
| Arts Taunton | Arts & recreation | 2015 |
| Arturio Books Limited | Wholesale & retail | 2015 |
| ARW HR Limited | Administrative & support | 2023 |
| AS Geotech Ltd | Professional & scientific | 2024 |
| AS9 Makes Limited | Manufacturing | 2025 |
| Asander Freehold Limited | Real estate | 2025 |
| Asander Investments Limited | Real estate | 2022 |
| Ascend Tendering Limited | Professional & scientific | 2014 |
| Ascending Phoenix Limited | Education | 2006 |
| Ascent Combat Sports Limited | Arts & recreation | 2014 |
| Ashbee and Elgar Ltd | Real estate | 2024 |
| Ashbrooke Homes Limited | Construction | 2012 |
| Ashbury Health Care Ltd | Health & social care | 2011 |
| Ashdown Barns Management Company Limited | Households | 2022 |
| Ashdown Gate RTM Company Limited | Real estate | 2006 |
| Ashleigh Gardens Management (Taunton) Limited | Real estate | 1972 |
| Ashleigh Property Ltd | Professional & scientific | 2017 |
| Ashley Colman Wealth Management (IFA) Ltd. | Financial services | 2011 |
| Ashlyn Property Investments Limited | Real estate | 2016 |
| Ashmead Farming Limited | Extraterritorial | 2004 |
| Ashridge Great Barn Limited | Real estate | 2015 |
| Ashton Court Management (Taunton) Limited | Households | 1974 |
| Ashwood Poultry Limited | Agriculture & fishing | 2016 |
| Askoncology Limited | Health & social care | 2015 |
| Aspen Maintenance Holdings Limited | Financial services | 2026 |
| Aspen Maintenance Services Limited | Other services | 2001 |
| Aspire 2 Design Ltd | Administrative & support | 2009 |
| Aspire Engineering Limited | Manufacturing | 2015 |
| Aspire House Solutions Ltd | Construction | 2017 |
| Aspirelet Holdings Ltd | Real estate | 2025 |
| Assisi Property Limited | Real estate | 2020 |
| Associated Roofing & Maintenance Limited | Construction | 1984 |
| Association of Reflexologists | Other services | 2005 |
| Assumpta Limited | Health & social care | 2024 |
| Astaires Limited | Wholesale & retail | 2004 |
| Aston Court Chambers WM LLP | | 2009 |
| Aston International Partnership Ltd | Real estate | 2008 |
| Aston Overseas Limited | Professional & scientific | 2025 |
| Astra Solutions Limited | Hospitality | 1997 |
| Astra Trading Development Ltd. | Other services | 2011 |
| Astral Services South West Ltd | Construction | 2025 |
| Astute Machinery Consultants Ltd | Professional & scientific | 2017 |
| Astute Town and Country Properties Limited | Real estate | 2024 |