| Art Strategics Limited | Professional & scientific | 2012 |
| Artech 2000 Limited | Construction | 1998 |
| Artem Restoration Ltd | Administrative & support | 2017 |
| Arth PVT Ltd. | Professional & scientific | 2014 |
| Arthur Court Property Management Limited | Hospitality | 2007 |
| Arthur Dalu (UK) Limited | Real estate | 2020 |
| Arthur's Barber Shop Limited | Other services | 2023 |
| Articulate Hands Ltd | Professional & scientific | 2011 |
| Artiisan Ltd | Administrative & support | 2004 |
| Artisan Brandt Limited | Information & communication | 1991 |
| Artisan Business Software Limited | Extraterritorial | 1997 |
| Artisan Food House Caterers Ltd | Hospitality | 2023 |
| Artisan Italian Ltd | Wholesale & retail | 2021 |
| Artley Enterprises Limited | Real estate | 2022 |
| Arts & Audio HQ Ltd | Arts & recreation | 2024 |
| Arts Nation Limited | Wholesale & retail | 2025 |
| Arturguzman Limited | Wholesale & retail | 2026 |
| Arun Place Phase II Management Limited | Households | 2003 |
| Arun Place Residents Management Limited | Households | 2002 |
| Arun Ramasamy Ltd | Wholesale & retail | 2019 |
| Arundel House (Bristol) Limited | Households | 2016 |
| Arunya Thai Massage Ltd | Other services | 2023 |
| Arushsteelstructural Limited | Construction | 2024 |
| Arxez Ltd | Information & communication | 2025 |
| Aryan Heating & Electrics Limited | Construction | 2016 |
| Aryan Homes Ltd | Construction | 2026 |
| Arzen Limited | Hospitality | 2024 |
| AS & K Property Developments Ltd | Real estate | 2025 |
| AS Barbers Limited | Other services | 2025 |
| AS Beauty Store Ltd | Wholesale & retail | 2025 |
| AS Catering Limited | Hospitality | 2024 |
| AS Costruzioni Ltd | Construction | 2025 |
| AS Fire & Alarms Ltd | Administrative & support | 2022 |
| AS Music Limited | Information & communication | 2023 |
| AS Property Maintenance Ltd | Construction | 2025 |
| AS Traders Ltd | Other services | 2013 |
| ASA Accounting Group Ltd | Professional & scientific | 2023 |
| ASA Hindu Wisdom Ltd | Information & communication | 2024 |
| ASA Trading Private Ltd | Wholesale & retail | 2026 |
| Asaa Regent Limited | Health & social care | 2024 |
| Asad Lahori Ltd | Wholesale & retail | 2025 |
| Asador Limited | Administrative & support | 2016 |
| Asafo Takeway Limited | Hospitality | 2023 |
| Asahi Photo Limited | Other services | 2002 |
| Asaman 1077 Limited | Health & social care | 2014 |
| Asanam Investments Limited | Real estate | 2019 |
| Asante Clothing Limited | Manufacturing | 2014 |
| Asap Roofing and Building Solutions Ltd | Construction | 2026 |
| Asare Bottah & Associates Limited | Professional & scientific | 2026 |
| Asbury Walk Management Company Limited | Households | 2011 |
| Ascend Self Hire Ltd | Administrative & support | 2025 |
| Ascension Cleaning Services Limited | Other services | 2017 |
| Ascension Global Services Ltd | Professional & scientific | 2013 |
| Ascent Realty Limited | Real estate | 2024 |
| Ascot Engineering & Bodyshop Limited | Wholesale & retail | 2016 |
| Ascot Logistics Ltd | Transport & logistics | 2019 |
| ASD Advisers Ltd | Professional & scientific | 2025 |
| Asdb Ltd | Construction | 2020 |
| Asean UK Business Forum (Aubf) Ltd | Other services | 2025 |
| Asegun Limited | Professional & scientific | 2003 |
| ASH & Co Accountants Ltd | Professional & scientific | 2006 |
| ASH Corporation Limited | Professional & scientific | 2016 |
| ASH Kaur Limited | Other services | 2011 |
| ASH Tree Fold Management Company Limited | Construction | 2026 |
| ASH View (Bowgreave) Management Company Limited | Households | 2020 |
| Asha Mini Mart Ltd | Wholesale & retail | 2021 |
| Asha Shirley Halal Ltd | Wholesale & retail | 2024 |
| Ashburn House (Resi) LLP | | 2015 |
| Ashburn Limited | Real estate | 1981 |
| Ashcare Services Limited | Health & social care | 2016 |
| Ashdene Builders Limited | Construction | 2016 |
| Ashdown House Residents Association Limited | Households | 2007 |
| Asher Freight and Logistics Ltd | Transport & logistics | 2026 |
| Ashfield House Management Limited | Households | 2002 |
| Ashfield Lodge Management Company Limited | Households | 1975 |
| Ashfields Court Residents Company Limited | Households | 2006 |
| Ashford Heating Supplies Limited | Wholesale & retail | 1988 |
| Ashlea House Residents Company Limited | Households | 1987 |
| Ashleigh Road Freehold Company Limited | Professional & scientific | 2009 |
| Ashley Care Limited | Health & social care | 2023 |
| Ashley Court (St.Johns) Management Company Limited | Households | 1988 |
| Ashley Court Residents Limited | Real estate | 1989 |
| Ashley Lane Management Limited | Households | 1984 |
| Ashley Neal Touring Limited | Arts & recreation | 2019 |
| Ashnaa Hair & Beauty Ltd | Other services | 2010 |
| Ashnaa London Academy Ltd | Education | 2024 |
| Ashra SPV Limited | Real estate | 2023 |
| Ashton Novella Ltd | Manufacturing | 2022 |
| Ashton Place Management Company Limited | Households | 1994 |
| Ashurst (Croydon) Ltd | Extraterritorial | 2018 |
| Ashurst Walton Limited | Financial services | 2017 |
| Ashvale (Aylesbury) Management Limited | Households | 1991 |
| Ashveena Limited | Real estate | 2013 |
| Ashwood Green (Sutton-In-Ashfield) Management Company Limited | Households | 2004 |
| Ashworth Mansions Limited | Households | 1990 |
| Asia Agency Ltd | Administrative & support | 2013 |
| Asia Daventry Limited | Hospitality | 2024 |
| Asia Fine Indian Cuisine Limited | Hospitality | 2026 |
| Asia Food Store Limited | Hospitality | 2015 |
| Asian Dhaba Ltd | Hospitality | 2018 |