| ALL Access Automation Ltd | Construction | 2024 |
| ALL at Sea Ltd | Construction | 2016 |
| ALL Battery Index Ltd | Information & communication | 2025 |
| ALL Car Solutions Ltd | Wholesale & retail | 2013 |
| ALL Hours Ltd | Administrative & support | 2017 |
| ALL Seasons Cleaning (SW) Ltd | Extraterritorial | 2009 |
| ALL Seasons Group Services (SW) Ltd | Other services | 2009 |
| ALL Seasons Landscape Ltd | Extraterritorial | 2009 |
| ALL the Best Ideas Ltd | Professional & scientific | 2019 |
| Allboat Services Limited | Other services | 2007 |
| Allbright Autos Ltd | Wholesale & retail | 2025 |
| Alldare Ltd | Information & communication | 2025 |
| Allen Licensed Holdings Limited | Hospitality | 2018 |
| Allen Welding Limited | Construction | 1999 |
| Aller Gardens Management Ltd | Households | 2021 |
| Aller Road Management Limited | Households | 2022 |
| Allhands Limited | Construction | 1979 |
| Alliance Legal Limited | Professional & scientific | 2019 |
| Alliance Search Ltd | Administrative & support | 2019 |
| Alliance-Pioneer Ambulance Ltd | Health & social care | 2012 |
| Alliance-Pioneer Assistance Ltd | Health & social care | 2025 |
| Alliance-Pioneer Healthcare Ltd | Health & social care | 2023 |
| Alliance-Pioneer Holdings Ltd | Financial services | 2024 |
| Alliance-Pioneer Medical Ltd | Health & social care | 2022 |
| Alliance-Pioneer Training Ltd | Education | 2022 |
| Allied Project Solutions Ltd | Professional & scientific | 2021 |
| Allied Tradesmen Limited | Construction | 2011 |
| Allround Homes & Developments Ltd | Construction | 2011 |
| Allspars (Holdings) Limited | Manufacturing | 2013 |
| Allspars EOT Ltd | Administrative & support | 2025 |
| Allspars Falmouth Ltd | Wholesale & retail | 2021 |
| Allspars Limited | Wholesale & retail | 2002 |
| Allspars Property Limited | Real estate | 2017 |
| Allup Homes Ltd | Real estate | 2025 |
| Allvolks Plymouth Ltd | Wholesale & retail | 2019 |
| Alma Cornwall Ltd | Real estate | 2012 |
| Alma Counselling and Learning Ltd | Education | 2015 |
| Alma Law Limited | Professional & scientific | 2017 |
| Alma SW Ltd | Real estate | 2012 |
| Almond Property Management Ltd | Real estate | 2010 |
| Almoor Properties Limited | Real estate | 2019 |
| Alpha Care SW Independent Limited | Health & social care | 2024 |
| Alpha Care SW Ltd | Health & social care | 2018 |
| Alpha Marine Services Limited | Professional & scientific | 2006 |
| Alpha Series Ltd | Wholesale & retail | 2025 |
| Alpha Services (Plymouth) Limited | Manufacturing | 1991 |
| Alphabet Signs (South West) Limited | Other services | 2008 |
| Alpure Ventures Limited | Professional & scientific | 2024 |
| Alston Hall Ltd | Hospitality | 2021 |
| Alston Manor Barns Limited | Households | 2006 |
| ALT Mobile Tyre Company Limited | Wholesale & retail | 2025 |
| ALT Real Estates Limited | Real estate | 2026 |
| Alter Results CIC | Professional & scientific | 2023 |
| Altilitech Ltd | Professional & scientific | 2020 |
| Altilium Clean Technology Ltd | Professional & scientific | 2022 |
| Altilium Ltd | Professional & scientific | 2022 |
| Altilium Metals Ltd | Professional & scientific | 2020 |
| Altitude Design Ltd | Information & communication | 2013 |
| Altitude Property Ltd | Real estate | 2019 |
| Alto Interiors Limited | Wholesale & retail | 2013 |
| Alto Kitchens Limited | Extraterritorial | 2013 |
| Alton Properties Ltd | Real estate | 2017 |
| Altus Access & Rescue Ltd | Professional & scientific | 2025 |
| Aluminium Windows Direct Ltd | Construction | 2025 |
| Alveo Solutions Limited | Professional & scientific | 2016 |
| Alvin Powell Motorsport LLP | | 2016 |
| Always Care Cornwall Ltd | Extraterritorial | 2017 |
| Always Roofing Ltd | Construction | 2022 |
| Alya Kevin Ltd | Public administration | 2023 |
| AM 2 PM Properties ( S W ) Ltd | Real estate | 2025 |
| AM Bookkeeping & Accounting Ltd | Professional & scientific | 2025 |
| AM Haircraft Ltd | Other services | 2020 |
| AM Restorations (UK) Ltd | Wholesale & retail | 2013 |
| AM Roofers Ltd | Construction | 2025 |
| AM Southwest Pubs Ltd | Hospitality | 2019 |
| Am-Dm Ltd | Arts & recreation | 2011 |
| Ama-Medicals Limited | Health & social care | 2022 |
| Amanda Fisk Consulting Ltd | Professional & scientific | 2019 |
| Amanda J Counselling & Wellbeing Ltd | Education | 2023 |
| Amandas Support Limited | Health & social care | 2025 |
| Amara Retreat Ltd | Other services | 2026 |
| Amare Property Ltd | Real estate | 2024 |
| Amazimus Ltd | Real estate | 2020 |
| AMB Home Improvements Ltd | Construction | 2011 |
| Amber Body Construction (Plymouth) Limited | Construction | 2015 |
| Amber Initiatives | Information & communication | 2005 |
| Amber Properties (Holdings) Limited | Real estate | 2019 |
| Amber Support Ltd | Information & communication | 2015 |
| Amber TOR Flats Management Limited | Other services | 1989 |
| Ambers Analytics Ltd | Financial services | 2014 |
| Ambience in a JAR Ltd | Wholesale & retail | 2025 |
| Ambylu Ltd | Manufacturing | 2020 |
| AMC Electrics Ltd. | Wholesale & retail | 2003 |
| Amch Services Ltd | Information & communication | 2017 |
| AMD Cars Ltd | Wholesale & retail | 2020 |
| Ameer Big Health Care Limited | Public administration | 2025 |
| Ameira Ltd | Wholesale & retail | 2025 |
| Americano B.G Ltd | Hospitality | 2017 |
| Amerland Ltd | Wholesale & retail | 2018 |
| Amethyst Properties (the Millfields) Ltd | Real estate | 2015 |