| Asante Creatives Ltd | Administrative & support | 2016 |
| ASB Leisure Limited | Wholesale & retail | 2018 |
| Asbg Global Ltd | Construction | 2024 |
| Ascendant Property Ltd | Real estate | 2026 |
| Ascent Valeting Ltd | Administrative & support | 2025 |
| Ascentia Solutions Limited | Information & communication | 2016 |
| Asguk (Systems) Limited | Manufacturing | 2002 |
| Asguk Holdings Limited | Real estate | 2024 |
| Asguk Maintenance Limited | Administrative & support | 2003 |
| ASH & Co. CS LLP | | 2007 |
| ASH & Sofe Ltd | Hospitality | 2024 |
| ASH & Sofia Ltd | Hospitality | 2023 |
| ASH & SUU Limited | Wholesale & retail | 2026 |
| ASH Mortgage Services Ltd | Financial services | 2025 |
| ASH White Holdings Limited | Education | 2022 |
| Ashbourne Trader Limited | Wholesale & retail | 2018 |
| Ashcroft Hall Management Company Limited | Households | 2010 |
| Ashdown Boiler Services Limited | Construction | 2011 |
| Ashford Road Management Company Limited | Real estate | 2023 |
| Ashk Engineering Services Ltd | Professional & scientific | 2025 |
| Ashlec Services Ltd | Construction | 2018 |
| Ashleworth Centre of Equestrian Services Limited | Agriculture & fishing | 2020 |
| Ashleworth Hub Ltd | Wholesale & retail | 2018 |
| Ashleworth Woodpeckers Sports and Social Club Limited | Arts & recreation | 2022 |
| Ashley Clarke Surveyors Ltd | Professional & scientific | 2021 |
| Ashley Davis Bodyshop Ltd | Wholesale & retail | 2024 |
| Ashley FOX Consulting Ltd | Professional & scientific | 2018 |
| Ashley House Anaesthesia Limited | Health & social care | 2019 |
| Ashley Paul Hairdressing Ltd | Other services | 2017 |
| Ashman Building Services Limited | Construction | 2025 |
| Ashmead & Wasley Property Ltd | Real estate | 2026 |
| Ashmore Court House Limited | Households | 2018 |
| Asian Directory Limited | Professional & scientific | 2014 |
| Asian Products & Services Ltd | Manufacturing | 2019 |
| Asiangrocer Hub Limited | Wholesale & retail | 2025 |
| Asko Commercial Appliances Limited | Manufacturing | 2025 |
| ASL Property & Investments Limited | Real estate | 2020 |
| ASP Healthcare Services Ltd | Health & social care | 2024 |
| Aspen Wood Flooring Ltd | Wholesale & retail | 2022 |
| Aspid Ltd | Information & communication | 2025 |
| Aspinline Limited | Wholesale & retail | 2013 |
| Aspirations (Midlands) Limited | Health & social care | 2004 |
| Aspirations (SL) Ltd | Health & social care | 2024 |
| Aspirations Care Limited | Health & social care | 2004 |
| Aspirations Outreach Limited | Health & social care | 2024 |
| Aspire Financial Planning Ltd | Financial services | 2005 |
| Aspire Investment Property Limited | Real estate | 2022 |
| Aspire Staffing Limited | Administrative & support | 2020 |
| ASR Hauliers Limited | Transport & logistics | 2016 |
| Assa Solutions Ltd | Information & communication | 2017 |
| Assembly Group Limited | Manufacturing | 2021 |
| Assessment Counts Ltd | Education | 2015 |
| Asset Acquisition Capital Limited | Information & communication | 2022 |
| Asset Management Services (UK) Ltd | Wholesale & retail | 2001 |
| Assured Contracting Services Ltd | Water & waste | 2023 |
| Assured Roofing and Property Maintenance Ltd | Construction | 2018 |
| Assured Roofing Supplies Ltd | Wholesale & retail | 2022 |
| Assured Time Ltd | Information & communication | 2021 |
| Asta Family Ltd | Wholesale & retail | 2023 |
| Astar Secure Services Limited | Administrative & support | 2021 |
| Astar Serviced Apartments Ltd | Real estate | 2017 |
| Astars Security Services Ltd | Administrative & support | 2025 |
| ASTERISK42 Ltd | Wholesale & retail | 2026 |
| Astg Accounting Limited | Professional & scientific | 2019 |
| Aston Architectural Design Limited | Professional & scientific | 2022 |
| Aston Green (Management) Limited | Households | 1991 |
| Aston Installations Ltd | Wholesale & retail | 2017 |
| Aston Parker Ltd | Transport & logistics | 2026 |
| Astra Construction Ltd | Construction | 2015 |
| Astrahive Ltd | Wholesale & retail | 2026 |
| Astrantia Design Services Ltd | Professional & scientific | 2019 |
| Astrocraft Consulting Ltd | Information & communication | 2013 |
| Astromezz Limited | Manufacturing | 1997 |
| AT Nelson Heating & Plumbing Ltd | Construction | 2013 |
| AT the Hill Ltd | Hospitality | 2025 |
| At-Teen Academy Ltd | Education | 2024 |
| Atgeeks Limited | Wholesale & retail | 2017 |
| Athelstan House (Gloucester) Management Co. Limited | Real estate | 2016 |
| Athena Cheltenham Ltd | Health & social care | 2017 |
| Athena's Cyberwarriors Ltd | Administrative & support | 2024 |
| Athene Ventures Limited | Financial services | 2021 |
| Atherton Jones Ltd | Professional & scientific | 2019 |
| Athina Chope Limited | Administrative & support | 2010 |
| Athlete Tracker Ltd | Education | 2024 |
| Athsai Consultants Ltd | Information & communication | 2013 |
| ATI Electrical Ltd. | Manufacturing | 2021 |
| Atips Ltd | Other services | 2015 |
| Atkinspm Ltd | Administrative & support | 2016 |
| ATL Private Hire & Airports Limited | Transport & logistics | 2018 |
| Atlantis Enterprise Ltd | Wholesale & retail | 2023 |
| Atrahasis Limited | Agriculture & fishing | 2023 |
| ATS Property Management Ltd | Real estate | 2017 |
| Attis Capital Ltd | Information & communication | 2022 |
| Attwood Insight Ltd | Information & communication | 2014 |
| AUA Communications Limited | Professional & scientific | 2012 |
| Auction Buyers 4U Limited | Wholesale & retail | 2016 |
| Audio Farm Studios Ltd | Information & communication | 2023 |
| Audio Junk Food Ltd | Information & communication | 2024 |
| Audiobob Ltd | Information & communication | 2019 |
| August Moon Tea Ltd. | Hospitality | 2016 |