| A L 10 Limited | Arts & recreation | 2016 |
| A M Ostler Electrical Limited | Construction | 2006 |
| A N Tarmacadam Ltd | Construction | 2022 |
| A R Mortgages Limited | Financial services | 2017 |
| A S Wills Limited | Extraterritorial | 2002 |
| A Team Electrical & Instrumentation Services Limited | Construction | 2015 |
| A U P (SW) Limited | Construction | 2006 |
| A&D Investments SW Limited | Real estate | 2023 |
| A&J Properties SW Ltd | Real estate | 2025 |
| A&R Managing Consultants Ltd | Professional & scientific | 2018 |
| A&T Trades Ltd | Financial services | 2025 |
| A.C. Hitchens Limited | Construction | 2002 |
| A.C.T Healthcare Limited | Health & social care | 2012 |
| A.P.D Security Solutions Limited | Administrative & support | 2023 |
| AA Property Designs Limited | Real estate | 2025 |
| AAF Financial Ltd | Professional & scientific | 2022 |
| AAF Financial Planning Europe Ltd | Professional & scientific | 2019 |
| Aarin Limited | Health & social care | 2025 |
| AASALES17 Ltd | Wholesale & retail | 2025 |
| AB Building & Landscaping Ltd | Administrative & support | 2025 |
| Abanico Salsa Ltd | Extraterritorial | 2007 |
| Abarbsbilt Property Co. Limited | Real estate | 1964 |
| Abbey 24X7 Limited | Wholesale & retail | 2022 |
| Abbey Meal Limited | Hospitality | 2019 |
| Abbey Sands Apartments Limited | Hospitality | 2019 |
| Abbot Electrical Services Limited | Manufacturing | 2016 |
| Abbotsmeed Limited | Administrative & support | 2011 |
| Aberfeldy Management Limited | Households | 2009 |
| Abfe Couriers Limited | Transport & logistics | 2020 |
| Abieris Limited | Real estate | 2014 |
| Abjd Limited | Information & communication | 2025 |
| Aboris Group Ltd | Financial services | 2025 |
| Above Town Trading Limited | Hospitality | 2014 |
| ABS Inc Ltd | Construction | 2011 |
| AC Carpentry SW Limited | Construction | 2021 |
| ACC Wood Limited | Manufacturing | 2017 |
| Accent International (Torquay) Limited | Education | 2021 |
| Accordant Care Limited | Health & social care | 2023 |
| Accountancy & Business Management Services Limited | Real estate | 1970 |
| Accountants Plus (SW) Limited | Professional & scientific | 2022 |
| Accounting IS Easy Limited | Professional & scientific | 2016 |
| Accucom Ltd | Professional & scientific | 2017 |
| Ace Electrical SW Ltd | Construction | 2026 |
| Ace Garden Services (SW) Ltd | Administrative & support | 2013 |
| Ace Pinoy and Asian Sari Sari Store Ltd | Wholesale & retail | 2024 |
| Ace Printwear Company Ltd | Wholesale & retail | 2018 |
| Ace Taxis Torbay Ltd | Transport & logistics | 2015 |
| Ace Workwear Ltd | Manufacturing | 2022 |
| Acland Plant Hire Limited | Construction | 2005 |
| Acorn Tree Care Limited | Agriculture & fishing | 2003 |
| ACR Plastering SW Ltd | Construction | 2025 |
| ACR Property Holdings SW Ltd | Real estate | 2022 |
| Acronymy Ltd | Information & communication | 2026 |
| Action Endurance Limited | Administrative & support | 2014 |
| Active Hospitality Solutions Ltd | Professional & scientific | 2010 |
| Acute Medical Ltd | Health & social care | 1994 |
| AD Augusta Limited | Information & communication | 2014 |
| AD Holmes Translations Limited | Professional & scientific | 2011 |
| Adam Designs IT Ltd | Extraterritorial | 2019 |
| Adamore Limited | Construction | 2022 |
| Adaptable Holdings Ltd | Professional & scientific | 2026 |
| Addison Tempest Limited | Professional & scientific | 1985 |
| Addisons Investments Limited | Real estate | 2004 |
| Addor Systems Limited | Administrative & support | 2023 |
| Adel Yachting Ltd | Professional & scientific | 2024 |
| Adesso Ltd | Arts & recreation | 2025 |
| Adflare Digital Limited | Manufacturing | 2025 |
| Adian Heating & Bathrooms Ltd | Construction | 2009 |
| Admirals Place Ltd | Real estate | 2019 |
| Adriatic Property Ltd | Real estate | 2025 |
| ADS Engineering Services Ltd | Information & communication | 2023 |
| Adswipe Ltd | Information & communication | 2015 |
| Advanced Development & Safety Laboratories Limited | Professional & scientific | 2008 |
| Advent Care Team Limited | Health & social care | 2008 |
| Advocacy South West Ltd | Information & communication | 2020 |
| Aegis Blue Limited | Administrative & support | 2024 |
| Aegis Roofing Contractors Limited | Construction | 2017 |
| Aegis Scaffolding Ltd | Construction | 2026 |
| AEM Spares Ltd | Wholesale & retail | 2021 |
| Aerial Edge (Devon) Ltd | Professional & scientific | 2015 |
| Aeroquant Ltd | Information & communication | 2026 |
| AES SW Limited | Other services | 2025 |
| Aesthetics LAB (SW) Ltd | Other services | 2020 |
| Affordable Homes in Manchester Limited | Real estate | 2012 |
| AFP Build Limited | Professional & scientific | 2020 |
| Afroauthentic Foods LLP Ltd | Hospitality | 2024 |
| AG Foulds Ltd | Real estate | 2026 |
| AGA Trans Limited | Construction | 2018 |
| Agar Management Consultancy Limited | Professional & scientific | 2015 |
| Agatha Christie Festival Limited | Education | 2014 |
| Agc-Media Ltd | Information & communication | 2026 |
| Agricultural & Industrial Roofing UK Ltd | Construction | 2025 |
| Agriwebeco Limited | Wholesale & retail | 2015 |
| AH Cleaning Solutions Ltd | Administrative & support | 2024 |
| AHU FM Limited | Construction | 2012 |
| Aimee Horrill Home Support Limited | Health & social care | 2023 |
| Aims E-Com Ltd | Wholesale & retail | 2025 |
| Air One Skydive Limited | Transport & logistics | 2013 |
| Aiton Douglas Ltd | Professional & scientific | 2023 |
| AJ Landscaping Ltd | Professional & scientific | 2020 |