| Architectural Stainless Design Ltd | Manufacturing | 2012 |
| Architecture Services Limited | Information & communication | 2020 |
| Arcomax Limited | Wholesale & retail | 2020 |
| Ardiez Ltd | Wholesale & retail | 2019 |
| Ares Networks Ltd | Construction | 2017 |
| Areyoushaw Ltd | Hospitality | 2025 |
| ARF Engg Limited | Information & communication | 2016 |
| ARG Contracting Ltd | Transport & logistics | 2015 |
| Arifi Cleaning Ltd | Other services | 2023 |
| Arisof Transport Ltd | Transport & logistics | 2024 |
| ARK Road Transport Ltd | Transport & logistics | 2019 |
| Arma Essentials Ltd | Wholesale & retail | 2025 |
| Armada Trading Co. Ltd | Wholesale & retail | 2017 |
| Armin Foundation CIC | Health & social care | 2025 |
| Armour Roofing & Guttering Ltd | Construction | 2025 |
| Armstrongs (Nuneaton) Limited | Professional & scientific | 2003 |
| Armstrongs Commercial Finance Ltd | Administrative & support | 2026 |
| Arnold Investments U.K. Limited | Real estate | 2021 |
| Aroma Boost Limited | Other services | 2021 |
| Arrowsmith Electrical Limited | Manufacturing | 2017 |
| Arshad Insight + Data Ltd | Information & communication | 2016 |
| Art Foods & Catering Ltd | Hospitality | 2026 |
| Art Lettings Group Limited | Real estate | 2026 |
| Arthi Convenience Store Ltd | Wholesale & retail | 2024 |
| Arts in Action CIC | Education | 2024 |
| Artushi Limited | Extraterritorial | 2017 |
| Arven Healthcare Ltd | Administrative & support | 2026 |
| Aryan Garages Limited | Wholesale & retail | 2024 |
| AS ENG Ltd | Professional & scientific | 2026 |
| Asanteman Midlands Coventry C.I.C. | Health & social care | 2026 |
| ASB Corporate Limited | Administrative & support | 2018 |
| ASB Plant Services Limited | Transport & logistics | 2020 |
| ASB Transport Limited | Transport & logistics | 2007 |
| ASB Tyres Limited | Wholesale & retail | 2019 |
| Asgl Ltd | Construction | 2016 |
| ASH J Labs Ltd | Manufacturing | 2025 |
| Ashby Boat Company Limited | Transport & logistics | 2006 |
| Ashby Canal Centre Limited | Extraterritorial | 2002 |
| Ashcourt Safety Training and Consultancy Limited | Professional & scientific | 2007 |
| Asherwood Limited | Wholesale & retail | 2019 |
| Ashmore Surveyors Limited | Professional & scientific | 2012 |
| Ashok Shinh Consulting Limited | Information & communication | 2012 |
| Ashton's Trading Limited | Wholesale & retail | 2024 |
| ASK Financial Limited | Hospitality | 2023 |
| ASK for Car Ltd | Transport & logistics | 2021 |
| ASK Transport Services Ltd | Transport & logistics | 2022 |
| Askar.Ortho Ltd | Health & social care | 2025 |
| ASM Sells Limited | Wholesale & retail | 2024 |
| Aspire 2 CM Limited | Real estate | 2021 |
| Aspire 2 Construction Limited | Construction | 2015 |
| Aspire 2 Developments Limited | Construction | 2012 |
| Aspire 2 Homes Limited | Construction | 2020 |
| Aspire 2 Maryvale Limited | Construction | 2021 |
| Aspire and Thrive Limited | Education | 2024 |
| Aspire in Arts CIC | Arts & recreation | 2015 |
| Assetplace Property Management Limited | Households | 1986 |
| Assets 4 Freedom Limited | Real estate | 2024 |
| Assured Living Care Services Limited | Public administration | 2023 |
| Assuretech Solutions Ltd | Information & communication | 2026 |
| Asta Property Developments Ltd | Real estate | 2025 |
| Astley Accountancy Services Limited | Professional & scientific | 2015 |
| Astley Church Farm Ltd | Agriculture & fishing | 2020 |
| Aston Road Garage Limited | Wholesale & retail | 2011 |
| Astranestrealty Ltd | Real estate | 2025 |
| Asupps Ltd | Wholesale & retail | 2024 |
| AT Betteridge Consultancy Limited | Information & communication | 2013 |
| ATB Holdings and Investments Ltd | Financial services | 2024 |
| ATC PUB Limited | Hospitality | 2025 |
| Athena HR Consultancy & Services Limited | Administrative & support | 2016 |
| Athena Insurance Services Limited | Financial services | 1992 |
| Atherstone and District Riding Club Limited | Arts & recreation | 2004 |
| Atlanta M&A Ltd | Professional & scientific | 2020 |
| Atlantic M Ltd | Transport & logistics | 2025 |
| Atlas Edge Consultancy Ltd | Real estate | 2025 |
| Atlas Trans Limited | Wholesale & retail | 2018 |
| Atlasaero Properties Ltd | Real estate | 2023 |
| Atoscaffolding Ltd | Construction | 2026 |
| ATS Applied Tech Systems Ltd. | Information & communication | 1991 |
| Attitude Baby Ltd | Wholesale & retail | 2019 |
| Attleborough Auto Centre Ltd | Wholesale & retail | 2022 |
| Attleborough Holdings Limited | Wholesale & retail | 2019 |
| Attleborough Service Station Limited | Wholesale & retail | 2023 |
| Atwork Clothing Limited | Wholesale & retail | 2000 |
| ATZ Scientific Services Ltd | Professional & scientific | 2025 |
| Auben Limited | Wholesale & retail | 2022 |
| Aubrey Collins Limited | | 2009 |
| Auction Plus Worldwide Limited | Other services | 2010 |
| Audio Force Productions Ltd | Administrative & support | 2023 |
| Audiovisual Rental Masters Ltd | Administrative & support | 2025 |
| Audrey & Stig Enterprises Ltd | Hospitality | 2013 |
| Augemus Holdings Limited | Financial services | 2020 |
| August Media Services Limited | Administrative & support | 2024 |
| Augusta Event Support Ltd | Administrative & support | 2019 |
| Aura Musical Events Limited | Arts & recreation | 2024 |
| Aureus Financial Services Limited | Financial services | 2005 |
| Auto Diagnostics (Midlands) Limited | Wholesale & retail | 2015 |
| Auto Forming Solutions Ltd | Professional & scientific | 2020 |
| Auto Installs Ltd | Construction | 2018 |
| Auto Technology (VAG) Ltd | Wholesale & retail | 2013 |
| Automizefit Ltd | Information & communication | 2025 |