| Affordable England LP | | 2011 |
| Agile Property Investors Ltd | Real estate | 2019 |
| AIM Property Consulting Ltd | Real estate | 2022 |
| Airdesk Technologies Ltd | Information & communication | 2026 |
| Airport Specialist Cars Limited | Transport & logistics | 2008 |
| Airsprung Beds Limited | Professional & scientific | 1965 |
| Airworthiness Solutions Ltd | Professional & scientific | 2024 |
| AIS Electrical Limited | Construction | 2025 |
| AJM Solutions Group Ltd | Professional & scientific | 2022 |
| AK Traderz Ltd | Manufacturing | 2021 |
| Akoa Limited | Real estate | 2022 |
| Akrent Ltd | Real estate | 2023 |
| ALD Property Ltd | Hospitality | 2020 |
| Alder Ecology UK Ltd | Professional & scientific | 2009 |
| Alderminster Custom Build Ltd | Construction | 2024 |
| Aldridge Accountants Limited | Extraterritorial | 2014 |
| Alert Data Limited | Administrative & support | 2018 |
| Alert Monitoring Limited | Administrative & support | 2018 |
| Alertsystems Group Limited | Administrative & support | 2013 |
| Alertsystems Limited | Administrative & support | 1995 |
| Alexian Freehold Limited | Real estate | 2023 |
| Alexian Property Ventures Ltd | Real estate | 2023 |
| Alford Advisory LLP | | 2006 |
| Alford Engineering Limited | Manufacturing | 2021 |
| Alford Explosive Demolition Limited | Construction | 2020 |
| Alford Explosives Consultancy Limited | Education | 2009 |
| Alford Family Holdings Limited | Financial services | 2026 |
| Alford Films Limited | Information & communication | 2018 |
| Alford IP Limited | Professional & scientific | 2003 |
| Alford Property Holdings Limited | Financial services | 2016 |
| Alford Technologies Limited | Professional & scientific | 1985 |
| Alford Technology Group Limited | Financial services | 2017 |
| Alford Training Limited | Education | 2011 |
| ALL Aspects Glass and Glazing Limited | Construction | 2022 |
| ALL Change Place Limited | Professional & scientific | 2017 |
| ALL Good Again Cookers Limited | Administrative & support | 2025 |
| ALL Ride DAS Limited | Education | 2019 |
| ALL Ride Motorcycle Training Ltd. | Education | 2017 |
| Alliance Renovations Ltd | Manufacturing | 2023 |
| Allied Carpets & Beds Limited | Wholesale & retail | 2022 |
| Allouaqui Dance Theatre Ltd | Arts & recreation | 2019 |
| Allum Limited | Wholesale & retail | 1991 |
| Almost Limited Company Ltd | Other services | 2024 |
| Altered Packet Limited | Information & communication | 2013 |
| ALU Roofing (UK) Ltd | Construction | 2021 |
| Always Better Than Yesterday Limited | Administrative & support | 2020 |
| AM Farms Limited | Extraterritorial | 2023 |
| Amageo Media Limited | Professional & scientific | 2012 |
| Amandeep Makeovers Ltd | Other services | 2026 |
| Amara Way Limited | Professional & scientific | 2018 |
| Ambrosia Global Ltd | Wholesale & retail | 2025 |
| AMO Technology Group Ltd | Information & communication | 2026 |
| Analytics HQ Ltd | Administrative & support | 2024 |
| Andrews Construction Consultants Limited | Construction | 2021 |
| Andtec Builders Ltd | Construction | 2008 |
| Angustifolia Estate Limited | Households | 2020 |
| Anna Fashionista Ltd | Wholesale & retail | 2023 |
| Antipodean Enterprises Limited | Information & communication | 2024 |
| Antur Arth Ltd | Construction | 2025 |
| Aphelion Core Ltd | Information & communication | 2023 |
| Apollo Electrical (SW) Ltd | Construction | 2014 |
| Aqua Blue Seafoods Limited | Extraterritorial | 1987 |
| Aquair Commissioning Services Ltd | Construction | 2009 |
| Archer Marketing Consultancy Ltd | Professional & scientific | 2026 |
| Architectural Mould Services Limited | Manufacturing | 2000 |
| Arctic Augmented Reality Technology Ltd. | Information & communication | 2017 |
| ARE YOU on Track Ltd | Professional & scientific | 2024 |
| Ariel Investments Limited | Professional & scientific | 2001 |
| Aristone (Property) Limited | Real estate | 2004 |
| Aristone Consulting Ltd | Construction | 2020 |
| Arko Gaming Ltd | Wholesale & retail | 2026 |
| Art Drop Ltd | Wholesale & retail | 2026 |
| Aruvi Convenience Store Ltd | Wholesale & retail | 2019 |
| Asborn Consultancy Limited | Professional & scientific | 2016 |
| ASH Bond Ltd | Information & communication | 2023 |
| Ashmore Property Development Limited | Construction | 2024 |
| Ashmore Transport Solutions Ltd | Transport & logistics | 2025 |
| Ashton Associates (Bath) Limited | Financial services | 2010 |
| Ashton Street Lessees Limited | Households | 2019 |
| ASK for Helen Limited | Professional & scientific | 2012 |
| Aspect Carpentry Ltd | Manufacturing | 2017 |
| Aston Interiors Limited | Wholesale & retail | 2006 |
| Astranti Connect Ltd | Education | 2021 |
| Astula Ltd | Information & communication | 2012 |
| ASV Portishead Limited | Wholesale & retail | 2022 |
| ASW Pest Control Specialists Limited | Professional & scientific | 1995 |
| ASW Property Solutions Ltd | Real estate | 2021 |
| Atelier Klaus Ltd | Wholesale & retail | 2024 |
| Audare Ltd | Wholesale & retail | 2018 |
| Audio Forum Limited | Administrative & support | 1997 |
| Audiocruise Enterprises Limited | Professional & scientific | 1994 |
| Aura Plumbing and Renovation Limited | Construction | 2024 |
| Automotive Service ROB Ltd | Wholesale & retail | 2026 |
| Automotive Training Services Limited | Education | 2019 |
| Avana Flooring Ltd | Wholesale & retail | 2020 |
| Avon Ecology Limited | Professional & scientific | 2024 |
| Avon Mews Residents Company Limited | Households | 2007 |
| Avonview Limited | Hospitality | 1994 |
| Ayreen Spice Limited | Hospitality | 2023 |
| Ayres Electrical Ltd | Construction | 2024 |