| Albert Court Weston-Super-Mare Maintenance Company Limited | Households | 1976 |
| Albertto Transport Ltd | Transport & logistics | 2019 |
| Albie John Ltd | Manufacturing | 2022 |
| Aldgate Security Ltd | Administrative & support | 2026 |
| Alee Properties (SW) Ltd | Real estate | 2024 |
| Aleksandrov a Company Ltd | Transport & logistics | 2019 |
| Aleqtra Limited | Professional & scientific | 2025 |
| Alere Healthcare Limited | Financial services | 2025 |
| Alere Properties Limited | Financial services | 2025 |
| Alex Developements Ltd | Real estate | 2018 |
| Alex Fast Delivery Ltd | Transport & logistics | 2022 |
| Alexander Hairdressing (Weston) Ltd | Other services | 2014 |
| Alexander MAE (Bristol) Ltd | Administrative & support | 2011 |
| Alina Transport Ltd | Transport & logistics | 2025 |
| Aline Driving School Ltd | Education | 2025 |
| Alis Logistics Ltd | Transport & logistics | 2021 |
| Alison Nurthen Ltd | Information & communication | 2024 |
| Alivia Nails & Beauty Limited | Other services | 2015 |
| ALL Business Service Ltd | Professional & scientific | 2021 |
| ALL Minis WSM Ltd | Wholesale & retail | 2023 |
| ALL of One Tattoos Limited | Other services | 2008 |
| ALL OUT South CIC | Health & social care | 2019 |
| ALL Saints Plumbing & Heating Ltd | Construction | 2025 |
| ALL Signs & Design Limited | Manufacturing | 2004 |
| ALL Voice Limited | Arts & recreation | 2013 |
| All-Round Electrical Ltd | Construction | 2019 |
| Alljay Transport Ltd | Transport & logistics | 2018 |
| Allstars (Bowl) Limited | Hospitality | 2022 |
| Allstars (Cardiff) Limited | Hospitality | 2018 |
| Allstars (Taunton) Limited | Hospitality | 2011 |
| Allstars (WSM) Limited | Hospitality | 2013 |
| Allure Smiles Ltd | Health & social care | 2024 |
| Almaclad Ltd | Construction | 2014 |
| Alphatec Systems Limited | Information & communication | 2009 |
| ALT Renewables Ltd | Manufacturing | 2023 |
| Altima Management Group Ltd | Administrative & support | 2019 |
| Altuk Limited | Manufacturing | 2022 |
| Alvacourt Limited | Construction | 1989 |
| Alvington Management Company Limited | Households | 2015 |
| Always Controls Ltd | Construction | 2019 |
| AM & LM Flooring Limited | Construction | 2026 |
| AMA Roofing Ltd | Construction | 2025 |
| Amadou J Ltd | Health & social care | 2021 |
| Amanda Spear Property Ltd | Real estate | 2025 |
| Amanda's Laser Clinic Ltd | Other services | 2024 |
| Amarc Europe Ltd | Other services | 2014 |
| Amayzing Properties Ltd | Real estate | 2022 |
| Amber N&C Ltd | Health & social care | 2016 |
| Amberleigh Supported Housing Limited | Hospitality | 2004 |
| Ambiente Bespoke Ltd | Construction | 2023 |
| Amble Care Ltd | Administrative & support | 2026 |
| Ameliviora Ltd | Wholesale & retail | 2025 |
| AMG Care Services Ltd | Health & social care | 2021 |
| AMG Heating Services Limited | Construction | 2021 |
| AMG Property Developments Ltd | Real estate | 2024 |
| Amgk Coaching Limited | Arts & recreation | 2019 |
| Amgw Property Ltd | Construction | 2025 |
| AMH Air Conditioning (South West) Limited | Energy | 2007 |
| Amicis Investments Limited | Real estate | 2022 |
| Amicis Lettings Ltd | Real estate | 2024 |
| Amitkainth Limited | Professional & scientific | 2013 |
| Amos Martin John 0568 Limited | Transport & logistics | 2014 |
| Ampbox Contracting Ltd | Construction | 2022 |
| Ample Estates Ltd | Real estate | 2026 |
| Amro Accountancy Ltd. | Professional & scientific | 2016 |
| Amrut Developments Ltd | Real estate | 2024 |
| Amulet Management Ltd | Real estate | 2021 |
| AMY Jackson Ltd | Arts & recreation | 2010 |
| AMY Russell Holdings Ltd | Financial services | 2023 |
| Amys Makeup Box Limited | Professional & scientific | 2019 |
| Andcro Ltd | Transport & logistics | 2025 |
| Andow Construction Ltd | Construction | 2019 |
| Andreas Daria Transport Ltd | Transport & logistics | 2025 |
| Andrew Morrison Ltd | Professional & scientific | 2017 |
| Andrews Heating Services Ltd | Construction | 2026 |
| Andrey Transport Limited | Transport & logistics | 2025 |
| Andy Cooling Ltd | Professional & scientific | 2020 |
| Andy Hall Cars Ltd | Wholesale & retail | 2012 |
| Ankest Limited | | 1982 |
| Anna Kebab Ltd | Hospitality | 2026 |
| Anna Valeting Ltd | Other services | 2018 |
| Annamani Creative Spaces Ltd | Hospitality | 2025 |
| Annaris Property Ltd | Real estate | 2024 |
| Anneset Productions Limited | Manufacturing | 2003 |
| ANS and AVI Limited | Hospitality | 2024 |
| Answergrid, Ltd | Information & communication | 2024 |
| Anthony Donovan Limited | Real estate | 1998 |
| Anthony Edward Dandy Ltd | Extraterritorial | 2024 |
| ANY Other Business Solutions Limited | Administrative & support | 2018 |
| Anything Goes Lifestyle Limited | Information & communication | 2015 |
| AO Gentz & Hair Co. Ltd | Other services | 2025 |
| Aowei Group UK Co., Ltd. | Extraterritorial | 2020 |
| AP7 Ltd | Information & communication | 2011 |
| Apache Construction Limited | Construction | 2015 |
| Apache Developments Limited | Real estate | 2017 |
| APC Management Ltd. | Professional & scientific | 2018 |
| Apocalipstick Entertainments Limited | Arts & recreation | 2025 |
| Apple County Clearances Limited | Water & waste | 2025 |
| Appletree Farm Management Limited | Households | 2006 |
| Approved Access Scaffolding (SW) Ltd | Construction | 2020 |