| ANM Consulting Ltd | Professional & scientific | 2013 |
| ANN Property Ltd | Real estate | 2021 |
| Annedh Properties Limited | Real estate | 2020 |
| Annette Ferguson Ltd | Professional & scientific | 2015 |
| Annie & Maude Limited | Wholesale & retail | 2020 |
| Ansome Ltd | Professional & scientific | 2005 |
| Anson Care Limited | Health & social care | 2023 |
| Ansum Cabs (Truro) Ltd | Transport & logistics | 2013 |
| Anthony & SON (Roussillon) Ltd | Hospitality | 1990 |
| Anthony Nguyen Ltd | Other services | 2025 |
| Anthonyis Limited | Information & communication | 2017 |
| Anyware IO Ltd | Information & communication | 2023 |
| AP Matthews Ltd | Real estate | 2025 |
| AP Media Consultancy Ltd | Information & communication | 2012 |
| Apartments for Falmouth Limited | Real estate | 2018 |
| Apex PM Ltd | Administrative & support | 2016 |
| Apis&Ursus Ltd | Manufacturing | 2021 |
| Apollo Consult Group PC | | 2017 |
| Apollo EC Truro Taxis Ltd | Transport & logistics | 2023 |
| Apricity Living Ltd | Health & social care | 2026 |
| APW Capital Goods Advisory Ltd | Professional & scientific | 2024 |
| Aqua Civils Limited | Construction | 2019 |
| Aqua Civils Projects Limited | Construction | 2026 |
| Aqua Nero (Water and Energy) Ltd | Water & waste | 2023 |
| Aqua Nero Marine Ltd | Manufacturing | 2022 |
| Aqua-Source (S.W.) Limited | Construction | 2003 |
| Aquavantage Limited | Manufacturing | 1997 |
| AR Alliance Ltd | Financial services | 2019 |
| Arbo Catering Ltd | Hospitality | 2024 |
| Archalian Ltd | Arts & recreation | 2017 |
| Archbishop Benson Church of England Primary School | Education | 2011 |
| Archer Holdings Limited | Real estate | 2015 |
| Archit Ltd | Real estate | 2022 |
| Architectural Services SW Ltd | Administrative & support | 2005 |
| ARE YOU NOT Entertained Limited | Hospitality | 2021 |
| Argray Management Company Limited | Households | 2023 |
| ARK Fire Safety Management Ltd | Professional & scientific | 2025 |
| ARK UN Limited | Financial services | 2026 |
| Armor Electrical Limited | Construction | 2012 |
| Armor Renewables Limited | Construction | 2023 |
| Armstrong Best Ltd | Arts & recreation | 2013 |
| Around Kernow Ltd | Hospitality | 2019 |
| Arrallas Barns Management Company Limited | Households | 1989 |
| Arren James Hymas Limited | Extraterritorial | 2024 |
| Arthritisfirst Limited | Health & social care | 2013 |
| Arthur's Club Ltd | Arts & recreation | 2026 |
| Artificial Grass Cornwall Limited | Construction | 2019 |
| Artist Liaison Ltd | Arts & recreation | 2023 |
| Arttos Ltd | Real estate | 2022 |
| Artura Design and Engineering Limited | Professional & scientific | 2016 |
| Arvow Bikes Ltd | Manufacturing | 2024 |
| ARW Scaffold Contracting Ltd | Construction | 2015 |
| Asbridge Consulting Limited | Real estate | 2022 |
| ASC Property Management Limited | Real estate | 2009 |
| Ashantihairportcompany Limited | Wholesale & retail | 2026 |
| Ashingdon Gardens (Block L) Management Company Limited | Households | 1993 |
| Ashita Holdings Limited | Financial services | 2024 |
| Ashwick Consulting Limited | Professional & scientific | 2024 |
| ASK Asbestos Services South West Ltd | Construction | 2019 |
| Askel Veur the Diocese of Truro Academies Umbrella Company Limited | Education | 2011 |
| Aspire Construction South West Limited | Construction | 2016 |
| Aspires Estate Management Ltd | Real estate | 2011 |
| Assay House Management Company Ltd | Households | 2026 |
| Assist AI Ltd | Information & communication | 2026 |
| Astaluna Ltd | Hospitality | 2026 |
| Asti Advisory Limited | Professional & scientific | 2026 |
| Astons Partners LP | | 2022 |
| Asubram Ltd | Real estate | 2023 |
| Atid DEV Ltd | Information & communication | 2026 |
| Atid Money Ltd | Professional & scientific | 2026 |
| Atlantic Arch Trading Limited | Administrative & support | 2021 |
| Atlantic Bay Flats Freehold Company Limited | Households | 2013 |
| Atlantic Bay Flats Management Company Limited | Households | 1987 |
| Atlantic Bay Hotel Limited | Real estate | 2016 |
| Atlantic Blankets Cornwall Limited | Wholesale & retail | 2014 |
| Atlantic Capital Markets Ltd | Financial services | 2016 |
| Atlantic Coast Studio Photography Ltd | Professional & scientific | 2025 |
| Atlantic Development Management Ltd | Construction | 2025 |
| Atlantic Energy Limited | Professional & scientific | 1992 |
| Atlantic Gate Ltd | Agriculture & fishing | 2006 |
| Atlantic Laundry & Linen Services Limited | Other services | 2024 |
| Atlantic Ortho Ltd | Wholesale & retail | 2023 |
| Atlantic Perioperative Ltd | Health & social care | 2026 |
| Atom Energy South West Limited | Construction | 2023 |
| Attachment and Trauma Training Services Ltd | Health & social care | 2026 |
| Attica Estate Ltd | Construction | 2025 |
| Atticus Property Limited | Real estate | 2005 |
| Attune Aesthetics Limited | Health & social care | 2024 |
| Audable Ltd | Extraterritorial | 2019 |
| Audley Chauffeuring Limited | Transport & logistics | 2012 |
| Augernisation Ltd | Construction | 2022 |
| Aukett Brockliss GUY Limited | Professional & scientific | 1999 |
| Auno Ltd | Information & communication | 2025 |
| Aussie Marquees Limited | Hospitality | 2006 |
| Austin Architecture & Design Ltd | Professional & scientific | 2017 |
| Automotive Brands Ltd | Wholesale & retail | 2013 |
| Aviation Solutions (Global) Limited | Administrative & support | 2024 |
| AVO Events Co Ltd | Hospitality | 2026 |
| AVS Service Centre Ltd | Wholesale & retail | 2014 |
| Axford Heaton Ltd | Construction | 2024 |