| Argyle Building Co. Limited | Construction | 1999 |
| Argyle Court Management Company(Southport)Limited | Administrative & support | 1964 |
| Argyle CT RTM Co Ltd | Households | 2026 |
| Argyle Developments (Southport) Ltd | Real estate | 2014 |
| Argyle House,Southport Management Co.Limited | Households | 1968 |
| Argyle Tennis Club Limited | Arts & recreation | 1922 |
| Ariah Services Limited | Extraterritorial | 2010 |
| ARK Executive Travel Limited | Transport & logistics | 2015 |
| ARK Toys Limited | Wholesale & retail | 1996 |
| ARK Travel Merseyside Ltd | Transport & logistics | 2025 |
| Arkenstone Building Consultancy Ltd | Professional & scientific | 2025 |
| Arkha Seeds Limited | Wholesale & retail | 2026 |
| Arleafletconsultants Limited | Transport & logistics | 2019 |
| Arma for New Curriculum Limited | Education | 2015 |
| Armed Forces Community Hub CIC | Health & social care | 2024 |
| Arnold Barron Properties Limited | Real estate | 2018 |
| Arnold Gorse Insurance Services Ltd | Financial services | 2004 |
| Aroma Leisure Ltd | Wholesale & retail | 2009 |
| Art Ease Northwest CIC | Education | 2024 |
| Artazan Hair Bar Ltd | Other services | 2014 |
| Arthur Cromwell & Foster Ltd | Professional & scientific | 2019 |
| Arti Partnership LLP | | 2023 |
| Artificial Turf Services Limited | Arts & recreation | 2023 |
| Artioukh (UK) Ltd. | Other services | 2016 |
| Artisan Business Solutions Limited | Administrative & support | 2022 |
| Artybitz Ltd | Wholesale & retail | 2019 |
| Artz for ALL C.I.C. | Arts & recreation | 2014 |
| Arundle International Limited | Information & communication | 2007 |
| Arvun Investments Limited | Real estate | 2020 |
| Ascension Scaffolding NW Limited | Construction | 2021 |
| Ascot Lodge Ltd | Health & social care | 2021 |
| Asemblr Ltd | Information & communication | 2016 |
| ASG Integrated Systems Ltd | Construction | 2018 |
| Asgard Estates Limited | Real estate | 2020 |
| Asgwestcoast Ltd | Wholesale & retail | 2024 |
| ASH Group Consulting Limited | Administrative & support | 2015 |
| Ashandmita Limited | Health & social care | 2026 |
| Ashbourne Gloucester Limited | Households | 2004 |
| Ashelway Limited | Real estate | 1960 |
| Ashfield Close Management Company Limited | Households | 2019 |
| Ashleighgroup Ltd | Real estate | 2022 |
| Ashley Jade Ltd | Education | 2024 |
| Ashley Jade Vocational College Ltd | Education | 2020 |
| Ashley James Property Solutions Limited | Real estate | 2026 |
| Ashton Allied Taxis Limited | Transport & logistics | 2020 |
| Ashton Engineering (Southport) Ltd | Manufacturing | 2012 |
| Ashworth Holdings Ltd | Real estate | 2009 |
| Ashworth Medical Services Ltd | Health & social care | 2025 |
| ASO Couriers Limited | Transport & logistics | 2023 |
| Aspect Letting & Management Limited | Real estate | 2017 |
| Aspen Gardens Management Company (NO 3) Limited | Households | 2011 |
| Aspire Solutions International Limited | Professional & scientific | 2024 |
| Asquith Estates Limited | Real estate | 2017 |
| Association of Northern Scaffolding Contractors | Other services | 2003 |
| Association of Surveyors and Valuers Ltd | Other services | 2024 |
| Assure Capital Ltd | Financial services | 2022 |
| Assuredhs Limited | Administrative & support | 2021 |
| Astraglaze (Northwest) Ltd | Construction | 2012 |
| Asumbala Garments Limited | Wholesale & retail | 2024 |
| AT Logistics Global Ltd | Transport & logistics | 2025 |
| At@Ut Limited | Real estate | 2017 |
| Atelier Roofing Ltd | Construction | 2023 |
| Athelstan Professional Consultancy Limited | Professional & scientific | 2021 |
| Athena Opco (Albert Road) Limited | Health & social care | 2023 |
| Athena Opco (Church Road) Limited | Health & social care | 2023 |
| Athena Opco (New Brighton One) Limited | Health & social care | 2023 |
| Athena Opco (New Brighton Two) Limited | Health & social care | 2023 |
| Athena Opco (Ormskirk) Limited | Health & social care | 2023 |
| Athena Opco (Oxford Road) Limited | Health & social care | 2023 |
| Athena Opco (Park Road) Limited | Health & social care | 2023 |
| Athena Opco (SNR) Limited | Health & social care | 2023 |
| Athena Taverna Ltd | Hospitality | 2024 |
| Atina Cafe Company Limited | Hospitality | 2026 |
| Atkins Property & Developments Ltd | Real estate | 2023 |
| Atlas Education and Recruitment Services Ltd | Administrative & support | 2023 |
| Atmosfear International Ltd | Arts & recreation | 2008 |
| ATR Wholesale Ltd | Administrative & support | 2012 |
| Atson Limited | Wholesale & retail | 1980 |
| Atty Limited | Wholesale & retail | 2026 |
| Atzi Ltd | Wholesale & retail | 2021 |
| AU Consulting Limited | Wholesale & retail | 2026 |
| AU Eyecare @ Home Limited | Health & social care | 2017 |
| Auberge Brasserie Limited | Hospitality | 2020 |
| Audio Jack Ltd | Information & communication | 2023 |
| Audrey Bond Properties Limited | Real estate | 2022 |
| Aughton Chase Flat Management Limited | Households | 2008 |
| August Twenty First Ltd | Professional & scientific | 2019 |
| Auraior Ltd | Wholesale & retail | 2025 |
| Aurento Ltd | Other services | 2025 |
| Auriemma Group Holdings Ltd | Financial services | 2011 |
| Aurum Designs Limited | Wholesale & retail | 2018 |
| Auto Dealer Force Limited | Information & communication | 2018 |
| Auto Dent Removal Ltd | Wholesale & retail | 2024 |
| Auto Elements Ltd | Wholesale & retail | 2010 |
| Autoclaritydirect Ltd | Wholesale & retail | 2019 |
| Autofy Ltd | Wholesale & retail | 2025 |
| Autograph Micar Limited | Wholesale & retail | 2003 |
| Autoinform Limited | Professional & scientific | 2019 |
| Automotive Consulting Engineers Ltd | Professional & scientific | 1997 |
| Autovault Motors Ltd | Wholesale & retail | 2026 |