| ALL Purpose Hair Ltd | Wholesale & retail | 2024 |
| ALL Textile Solutions Ltd | Wholesale & retail | 1993 |
| ALL Things Gardening Limited | Administrative & support | 2020 |
| Allard & Company,Limited | Construction | 1912 |
| Allbuild Limited | Construction | 1987 |
| Allday Healthcare Ltd | Health & social care | 2024 |
| Allday Mobility Ltd | Transport & logistics | 2023 |
| Allday Multiservice Ltd | Construction | 2023 |
| Allenanastasia Limited | Health & social care | 2023 |
| Alliance Security Limited | Administrative & support | 2003 |
| Allmat (East Surrey) Limited | Wholesale & retail | 1991 |
| Allsector Property Services Ltd | Water & waste | 2025 |
| Almarwa Group Ltd | Mining & quarrying | 2025 |
| Almost Perfect Interiors Limited | Wholesale & retail | 2022 |
| Alpha Ventures Surrey Ltd | Real estate | 2024 |
| Alpsbury Solutions Ltd | Professional & scientific | 2017 |
| Alsted Manor Estates Limited | Real estate | 2024 |
| Alsted Manor Tree Care Ltd | Agriculture & fishing | 2022 |
| Altera Ltd | Construction | 2025 |
| Alterego Consultancy Limited | Wholesale & retail | 2015 |
| Alternative Smart Solutions Ltd | Health & social care | 2018 |
| Althorne Project Consultants Ltd | Professional & scientific | 2022 |
| Alvaherne Limited | Construction | 1980 |
| Alvia Gardens (Sutton) Management Limited | Households | 1987 |
| Alvia Gardens Freehold Company Limited | Households | 2017 |
| Always BE Happy Limited | Health & social care | 2012 |
| AM People OPS Ltd | Professional & scientific | 2026 |
| AM PM Tyres Ltd | Wholesale & retail | 2024 |
| AM Pool Service Ltd | Construction | 2020 |
| Amaste Ownership Ltd | Financial services | 2024 |
| Amazing Care Limited | Administrative & support | 2025 |
| Ambrosi (UK) Limited | Financial services | 2018 |
| Amevarda Limited | Real estate | 2022 |
| AMH Industries Limited | Information & communication | 2013 |
| Amie Electro Limited | Construction | 2019 |
| Amor Vincit Productions Limited | Professional & scientific | 2005 |
| Amos Villas Management Company Limited | Households | 2019 |
| AMP132 Limited | Financial services | 2017 |
| Amren Services Limited | Professional & scientific | 2006 |
| Amritt Private Limited | Real estate | 2019 |
| AMS Graphic Machinery Limited | Wholesale & retail | 2005 |
| AMS Khan Limited | Real estate | 2021 |
| AMX Solutions Limited | Information & communication | 2004 |
| Amygdala Media Limited | Information & communication | 2012 |
| Anand & Sons Ltd | Wholesale & retail | 2020 |
| Anchor Simpatico Ltd | Financial services | 2020 |
| Andest Limited | Transport & logistics | 2020 |
| Andrew JEE Limited | Administrative & support | 2009 |
| Andrew Motors Ltd | Wholesale & retail | 2024 |
| Anex Management and Consulting Ltd | Professional & scientific | 2024 |
| Angle Aesthetics Ltd | Other services | 2020 |
| ANM Home Investments Ltd | Real estate | 2022 |
| Anna D. Lascsik Ltd. | Arts & recreation | 2017 |
| Anns Walk Bletchingley Management Limited | Households | 2007 |
| Annsolutions Ltd | Information & communication | 2023 |
| Ansa Garden Designs Limited | Administrative & support | 2016 |
| Ansel Technology Solutions Ltd | Administrative & support | 2012 |
| Anthony Rowcliffe and SON Limited | Wholesale & retail | 1988 |
| Antique Tree Ltd | Wholesale & retail | 2023 |
| Anxious Flyer Airline Review (Afar) Ltd | Administrative & support | 2024 |
| Anytime Repairs Ltd | Construction | 2023 |
| Aorinda Limited | Real estate | 2020 |
| AP Finance Limited | Financial services | 2026 |
| APA Corporation Ltd | Construction | 2019 |
| Apex Quad Parts Ltd | Wholesale & retail | 2025 |
| API Rhino Limited | Information & communication | 2014 |
| Applecross Building Company Ltd | Construction | 2009 |
| Applewood Mortgages Ltd | Financial services | 2020 |
| Aqua Air Hygiene Solutions (CPS) Limited | Construction | 2017 |
| Aqua Warm Ltd | Construction | 2020 |
| Arabella Property Portfolio 1 Ltd | Real estate | 2020 |
| Arain Ventures Ltd | Real estate | 2024 |
| Arbor Square Associates Limited | Professional & scientific | 2006 |
| Arcadia Gaming Lounges Limited | Arts & recreation | 2025 |
| Archemys Care Services Limited | Health & social care | 2024 |
| Archilton Ltd | Information & communication | 2018 |
| Architecture.Com Ltd | Professional & scientific | 2003 |
| Ardas Logistics Ltd | Transport & logistics | 2026 |
| Ardo Lifts Ltd | Construction | 2021 |
| Areru Ltd | Information & communication | 2025 |
| Arise & Shine Beauty Limited | Hospitality | 2015 |
| ARK Blinds & Awnings Limited | Construction | 2014 |
| Arla Foods Ingredients Amba | | 2004 |
| Arlberg Capital Ltd | Financial services | 2013 |
| Armer Residential Ltd | Real estate | 2025 |
| Armour Fire Solutions Ltd | Construction | 2020 |
| Armourco Consulting Ltd | Professional & scientific | 2015 |
| Armourco Property Limited | Real estate | 2016 |
| ARR Holdings Ltd | Real estate | 2021 |
| Arti Secure Ltd | Financial services | 2025 |
| Arti Security Solution Ltd | Financial services | 2025 |
| Artific Ltd | Information & communication | 2024 |
| Artisan Coffee Co Limited | Manufacturing | 2007 |
| Artisan Coffee V1 Limited | Wholesale & retail | 2019 |
| Artisania Limited | Wholesale & retail | 2012 |
| Aruj Limited | Health & social care | 2020 |
| Arundel Care Group Limited | Health & social care | 2023 |
| Arundel Care Services Holdings Limited | Health & social care | 2015 |
| Arundel Care Services Limited | Health & social care | 2004 |
| Arundel Domiciliary Care Services Limited | Health & social care | 2007 |