| ADL4 Development Limited | Construction | 2021 |
| ADM Property Lettings Limited | Real estate | 2017 |
| Admiral Square Apartments Ltd | Hospitality | 2018 |
| Admiral Square Consultancy Ltd | Professional & scientific | 2018 |
| Admiral Square Properties Limited | Real estate | 2017 |
| Adore Children Ltd | Health & social care | 2021 |
| Adrian Broadway Ltd | Construction | 2021 |
| ADS Windows and Doors Limited | Other services | 2009 |
| Adswand Limited | Other services | 2020 |
| Adthority Ltd | Administrative & support | 2014 |
| Aduvi Limited | Information & communication | 2018 |
| Advance Environmental Consulting Limited | Professional & scientific | 2016 |
| Advance Health Consulting Limited | Health & social care | 2021 |
| Advance Joinery Group Ltd | Manufacturing | 1994 |
| Advanced Arboriculture Limited | Agriculture & fishing | 2017 |
| Advanced Excellence Limited | Professional & scientific | 2026 |
| Advanced Media Engineering Limited | Information & communication | 2000 |
| Advanced Security Alarm Protection Limited | Construction | 2004 |
| Advanta Wealth (South West) Holdings Ltd | Financial services | 2019 |
| Advantage Solutions Limited | Professional & scientific | 2009 |
| Advantage Southwest LLP | | 2003 |
| Advantage Tennis Services Ltd | Arts & recreation | 2023 |
| Adventurous Appetites Limited | Administrative & support | 2003 |
| Adviser (156) Limited | Real estate | 1990 |
| Advoc Europe Limited | Other services | 2013 |
| Advoc Limited | Professional & scientific | 1991 |
| Aegis Tactical Solutions Ltd | Wholesale & retail | 2025 |
| Aepollo Ltd | Construction | 2024 |
| Aerial Services SW Limited | Information & communication | 2022 |
| Aerice Consulting Limited | Professional & scientific | 2017 |
| Aerice Holdings Limited | Professional & scientific | 2020 |
| Aerinnova UK Ltd | Water & waste | 2023 |
| Aeris Aviation Limited | Wholesale & retail | 2012 |
| Aero Management Limited | Professional & scientific | 2022 |
| Aero X Direct Ltd | Manufacturing | 2023 |
| Aesthetica Medical Spa Limited | Health & social care | 2019 |
| Aesthetics Inc Ltd | Other services | 2021 |
| Aestima Limited | Professional & scientific | 2011 |
| Aestimo Limited | Professional & scientific | 2020 |
| Aetcs Electrical Contractors Ltd | Construction | 2017 |
| Aeterna Aesthetics Ltd | Other services | 2024 |
| Aeternal Limited | Other services | 2011 |
| AF External Works Limited | Construction | 2025 |
| AF Property Maintenance and Management Limited | Real estate | 2024 |
| Affinity Lake View Limited | Construction | 2014 |
| Affinity Property Development Limited | Construction | 2010 |
| Affinity Staffing Services Limited | Administrative & support | 2019 |
| Afghan Community Devon CIC | Education | 2022 |
| Afghan Community Exeter CIC | Other services | 2024 |
| Afit Commercial Ltd | Construction | 2015 |
| AFL Health Limited | Health & social care | 2020 |
| AFL Investment & Assets Limited | Real estate | 2021 |
| African Coffee Limited | Wholesale & retail | 2018 |
| Africana Ltd | Transport & logistics | 2018 |
| Afterbuild Care Limited | Construction | 2026 |
| Afterstone Ltd | Other services | 2025 |
| AG Climatics Ltd | Construction | 2019 |
| AGE UK Devon | Health & social care | 1992 |
| AGE UK Devon Trading Limited | Financial services | 2012 |
| AGE UK Exeter | Health & social care | 1992 |
| Agelis Peltier Ltd | Wholesale & retail | 2022 |
| AGENTS4RM Limited | Professional & scientific | 2009 |
| Agilify Ltd | Professional & scientific | 2008 |
| AGL Commodities Ltd. | Information & communication | 2026 |
| Aglow Kitchen Repairs and Servicing Limited | Manufacturing | 2016 |
| AGP Commercial Property Ltd | Real estate | 2026 |
| AGP Property Development Ltd | Real estate | 2021 |
| AGP Property Solutions Ltd | Real estate | 2020 |
| Agri Market Insight & Access Ltd | Professional & scientific | 2012 |
| Agri-Hub Ltd | Professional & scientific | 2025 |
| AGS Building and Groundworks (UK) Ltd | Construction | 2019 |
| AGS Ground Solutions Limited | Construction | 2014 |
| AGS Rail Limited | Professional & scientific | 2024 |
| Agua Bars & Clubs Ltd | Hospitality | 2025 |
| Aguy Ltd | Health & social care | 2023 |
| AH Commercial Property Company Ltd | Real estate | 2025 |
| AH Residential Property Company Ltd | Households | 2025 |
| AH UK Tech Limited | Extraterritorial | 2017 |
| AHA Exeter Property Ltd | Real estate | 2018 |
| AHB Invest Limited | Professional & scientific | 2022 |
| AHB Property Rentals Limited | Real estate | 2021 |
| AHK Taxi Limited | Transport & logistics | 2026 |
| Ahoy Equity Ltd | Professional & scientific | 2021 |
| Ahsani Development Services Limited | Real estate | 2024 |
| Ahsani Valeting Limited | Administrative & support | 2026 |
| AI Tandoori Ltd | Hospitality | 2024 |
| AI Workflows Ltd | Information & communication | 2024 |
| Aify’S Child Care Limited | Health & social care | 2025 |
| AIM Excelsis Ltd | Real estate | 2018 |
| Air Fresh Services Limited | Manufacturing | 2014 |
| Air Marketing Group Limited | Professional & scientific | 2016 |
| Air Marketing Limited | Professional & scientific | 2019 |
| Air Property UK Ltd | Real estate | 2020 |
| Aircasa Limited | Real estate | 2021 |
| Aircraft Paint Services Limited | Professional & scientific | 2014 |
| Airline IT Consulting Limited | Other services | 2018 |
| Airport Direct Parking Limited | Extraterritorial | 2011 |
| Airport Direct Travel Limited | Information & communication | 2006 |
| Airport Meet & Greet Parking Limited | Transport & logistics | 2025 |
| Airwars | Other services | 2016 |