| Ashton Project Services Ltd | Professional & scientific | 2013 |
| Ashton Wheel Centre Ltd | Wholesale & retail | 2025 |
| Ashurst Bathrooms & Wetrooms Ltd | Construction | 2018 |
| Ashurst Development NW Ltd | Construction | 2023 |
| Ashworth CBT Ltd | Health & social care | 2019 |
| Asian Kitchen Hull Limited | Hospitality | 2020 |
| Asixsigma Limited | Information & communication | 2004 |
| Ask.F Ltd | Transport & logistics | 2013 |
| ASL 2021 Limited | Real estate | 2021 |
| ASM Building Services Limited | Construction | 2008 |
| ASM Driver Services Ltd | Transport & logistics | 2025 |
| ASO Building Services Ltd | Construction | 2019 |
| Aspect Civil Engineering Ltd | Construction | 2022 |
| Aspect Interior Design Ltd | Construction | 2020 |
| Aspect Lifetime Services Ltd | Financial services | 2014 |
| Aspect Mortgages Limited | Financial services | 2004 |
| ASPECT2I Limited | Information & communication | 2009 |
| Aspects of Expression Ltd | Extraterritorial | 2019 |
| Aspen and IVY Events Ltd | Professional & scientific | 2025 |
| Aspen Financial Management Ltd | Professional & scientific | 2015 |
| Aspirational Futures Multi-Academy Trust | Education | 2012 |
| Aspire Gyms Limited | Arts & recreation | 2013 |
| ASR Joinery Ltd | Construction | 2023 |
| Assembled Joinery Limited | Manufacturing | 1994 |
| Assessor Plus Ltd. | Administrative & support | 2018 |
| Asshawes 1955 Limited | Extraterritorial | 2013 |
| Assured FD Services Limited | Professional & scientific | 2021 |
| Assured Process Servers Limited | Extraterritorial | 2020 |
| Assured Procure Ltd | Administrative & support | 2010 |
| Assuredtalk Limited | Information & communication | 2024 |
| Asterisk Direct Limited | Manufacturing | 2004 |
| Asterisk Services Limited | Other services | 2017 |
| Astley Inn Limited | Hospitality | 2026 |
| Asto Clinics Charity Ltd | Health & social care | 2020 |
| Asto Clinics Ltd | Health & social care | 2019 |
| Astraseal Investment Properties Limited | Real estate | 2016 |
| Astraseal Mastics Limited | Construction | 2007 |
| Astronomic Music Ltd | Information & communication | 2013 |
| Astute Project Management Limited | Construction | 2017 |
| AT Home With Ruth Limited | Manufacturing | 2017 |
| ATC Logistics Ltd | Transport & logistics | 2022 |
| Athena Roofing Services (Rochdale) Ltd | Administrative & support | 2009 |
| Athena Supply Chain Solutions Limited | Information & communication | 2024 |
| Athletico Buckshaw Futsal Ltd | Arts & recreation | 2018 |
| Atkinson Brookes Limited | Wholesale & retail | 2024 |
| ATL Engineering Limited | Construction | 2014 |
| ATL Fulfilment Limited | Transport & logistics | 2013 |
| ATL2411 Enterprise Ltd | Hospitality | 2024 |
| Atlas Group (Midlands) Ltd | Construction | 2021 |
| ATM Services (SW) Limited | Construction | 2009 |
| Atpa Construction Ltd | Construction | 2019 |
| Attention to Detailing Chorley Ltd | Administrative & support | 2024 |
| Attitude Academy Ltd | Education | 2020 |
| AU Refinery UK Ltd | Wholesale & retail | 2025 |
| Auctioneersuk Ltd | Administrative & support | 2025 |
| Audit Comms Ltd | Construction | 2015 |
| Audit Coms Ltd | Extraterritorial | 2015 |
| Auditor Competence Trusted Assessment Limited | Professional & scientific | 2025 |
| Auditorium Hearing Ltd | Wholesale & retail | 2025 |
| Aunty Betties Hair Product Limited | Wholesale & retail | 2014 |
| Aurelius Property Assets Ltd | Real estate | 2025 |
| Auris Interpreting Services Ltd | Professional & scientific | 2023 |
| Austen Properties Ltd | Real estate | 2019 |
| Austen Property Group Ltd | Real estate | 2020 |
| Auto Hanse 42 GmbH Ltd | Wholesale & retail | 2026 |
| Autocentre Limited | Wholesale & retail | 2006 |
| Autofit Limited | Extraterritorial | 2007 |
| Automatic Gate and Barrier Experts Ltd | Construction | 2023 |
| Automation Guaranteed by Expert Services Ltd | Construction | 2025 |
| Automotive Mobile Service Limited | Wholesale & retail | 2025 |
| Automotive Motors Ltd | Wholesale & retail | 2016 |
| Autoresolutions Limited | Information & communication | 2016 |
| Autoscientific Ltd | Professional & scientific | 2021 |
| AVA Rose Hair Studio Ltd | Other services | 2009 |
| Avacabs Chorley Ltd | Transport & logistics | 2023 |
| Avalon Management Consulting Ltd | Professional & scientific | 2015 |
| Avam Solutions Ltd | Professional & scientific | 2019 |
| Avant SIA Ltd | Health & social care | 2019 |
| Avant-Garde Transformations Ltd | Professional & scientific | 2022 |
| Avec Cookers (UK) Ltd | Manufacturing | 2011 |
| Aveling Logistics Limited | Transport & logistics | 2016 |
| Averge Bidco Limited | Financial services | 2023 |
| Avid Healthcare and Recruitment Ltd | Administrative & support | 2017 |
| Avocet Property Improvements Ltd | Construction | 2024 |
| Avon Financial Advisers Limited | Extraterritorial | 2002 |
| Avove Limited | Administrative & support | 1991 |
| AW Fire Safety Ltd | Construction | 2022 |
| AW Properties (North West) Ltd | Real estate | 2017 |
| AW Roofing (North West) Ltd | Construction | 2012 |
| Awc-Ec & I Limited | Information & communication | 2015 |
| Awel Energy Ltd | Professional & scientific | 2024 |
| Awel Resources Ltd | Administrative & support | 2025 |
| Awesome Moon Trade Ltd | Wholesale & retail | 2024 |
| AWL Engineering Limited | Manufacturing | 2004 |
| Awol Adventure Limited | Information & communication | 2012 |
| AWT Development Holdings Limited | Financial services | 2020 |
| AWT Sourcing Limited | Real estate | 2018 |
| AXA Power Limited | Energy | 2019 |
| Axel Tech Services Ltd | Information & communication | 2020 |
| Axis Legal Services Limited | Professional & scientific | 2018 |