| Amethyst Autos Limited | Wholesale & retail | 2025 |
| Amnesty Estelle Ltd | Information & communication | 2022 |
| Amorc Services Limited | Information & communication | 1992 |
| Anahi Collection Limited | Wholesale & retail | 2014 |
| Analogy Consulting Limited | Professional & scientific | 2023 |
| Anamato Ltd | Information & communication | 2019 |
| Andrew Tiernan Limited | Information & communication | 2010 |
| Aneen Ventures Limited | Wholesale & retail | 2015 |
| Angel's Business Solutions Ltd | Professional & scientific | 2020 |
| Angrove House Limited | Households | 1959 |
| Anidea Limited | Real estate | 2003 |
| Annex Developments Limited | Administrative & support | 2008 |
| Annunciation Limited | Professional & scientific | 2015 |
| Ansell House Management Limited | Households | 2023 |
| Anti-Climb Guards Limited | Manufacturing | 1998 |
| Anylastorders Limited | Hospitality | 2013 |
| Apex Andaman Limited | Professional & scientific | 2011 |
| Apex Asia Property Investors Limited | Real estate | 2011 |
| Apex Electronics Limited | Wholesale & retail | 1990 |
| Aquamour Limited | Wholesale & retail | 2021 |
| Aquavibe Pro Limited | Manufacturing | 2026 |
| Archand Design Limited | Professional & scientific | 2023 |
| Archer Roofing (Kent) Limited | Construction | 2017 |
| Arcray Webmedia Limited | Information & communication | 2000 |
| Ardwolf Limited | Wholesale & retail | 2008 |
| Argos Hill (Gables) Residents Association Limited(The) | Professional & scientific | 1971 |
| Argos Hill Windmill Trust Limited | Administrative & support | 2010 |
| Aritia Ltd | Information & communication | 2021 |
| Arnell Ltd | Construction | 2009 |
| Aros Morfose Barbers Ltd | Other services | 2021 |
| Artytime Community Interest Company | Education | 2018 |
| ASF Tyres (UK) Limited | Wholesale & retail | 2005 |
| Ashdown Appointments Ltd. | Administrative & support | 2010 |
| Ashdown Building Contractors Limited | Construction | 2023 |
| Ashdown Consultancy Services Limited | Construction | 2019 |
| Ashdown Executive Search (UK) Ltd | Administrative & support | 2009 |
| Ashdown Homes (Sussex) Limited | Construction | 2017 |
| Ashleigh Gardens Residents Association Limited | Households | 1995 |
| Aspal Country Park Ltd | Hospitality | 2024 |
| Aspen Property Management Ltd | Real estate | 2003 |
| Assassins Thai Boxing Limited | Arts & recreation | 2023 |
| Asset 1 Opsh Limited | Professional & scientific | 2024 |
| Asset 10 OP Limited | Professional & scientific | 2024 |
| Asset 10 Opsh Limited | Professional & scientific | 2024 |
| Asset 2 Opsh Limited | Professional & scientific | 2024 |
| Asset 3 OP Limited | Professional & scientific | 2024 |
| Asset 3 Opsh Limited | Professional & scientific | 2024 |
| Asset 4 OP Limited | Professional & scientific | 2024 |
| Asset 4 Opsh Limited | Professional & scientific | 2024 |
| Asset 5 OP Limited | Professional & scientific | 2024 |
| Asset 5 Opsh Limited | Professional & scientific | 2024 |
| Asset 6 Opsh Limited | Professional & scientific | 2024 |
| Asset 7 OP Limited | Professional & scientific | 2024 |
| Asset 7 Opsh Limited | Professional & scientific | 2024 |
| Asset 8 OP Limited | Professional & scientific | 2024 |
| Asset 8 Opsh Limited | Professional & scientific | 2024 |
| Association of Service Drop-In Centres Ltd | Other services | 2020 |
| Assured Property Maintenance and Renovation Limited | Households | 2018 |
| Aston (Estate Agents) Limited | Real estate | 1978 |
| Atelier (Lewes) Ltd | Construction | 2019 |
| Aterny Agile Services Ltd. | Professional & scientific | 2015 |
| Atlas & Boots Ltd | Information & communication | 2016 |
| Attwood & Sons Properties Limited | Real estate | 2014 |
| Aubury Holdings Limited | Financial services | 2024 |
| Audio Engineer Ltd | Administrative & support | 2018 |
| AUR Investments Limited | Financial services | 2024 |
| Avens Ltd | Health & social care | 1994 |
| Aviou Law Firm Limited | Professional & scientific | 2025 |
| AWR Autos Limited | Wholesale & retail | 2024 |
| AWS International Business Development Limited | Professional & scientific | 2001 |
| Axiom Solutions Limited | Professional & scientific | 2025 |
| Axpm Services Ltd | Agriculture & fishing | 2018 |
| Ayna (UK) Limited | Information & communication | 2005 |
| Ayni Ltd | Education | 2015 |
| Azomemo Ltd | Hospitality | 2023 |
| B & W Electrical Contractors Limited | Administrative & support | 2006 |
| B D Woodgate Limited | Professional & scientific | 2005 |
| B G Motor Services Limited | Wholesale & retail | 2000 |
| B W Woolpack Ltd | Real estate | 2025 |
| B.D. Properties Limited | Real estate | 1995 |
| Babazula Limited | Arts & recreation | 2021 |
| Bacg Analysts Limited | Information & communication | 2010 |
| Baker Associates (Developments) Limited | Professional & scientific | 2000 |
| Baldwin Boxall Communications Limited | Manufacturing | 1982 |
| Baldwin Plastering Limited | Construction | 2015 |
| Bar Group Ltd | Information & communication | 2019 |
| Bark Bites Ltd | Wholesale & retail | 2023 |
| Barney Leisure Ltd | Construction | 2020 |
| Baron Realty Limited | Construction | 2020 |
| Baronsmede Support Services Limited | Health & social care | 2015 |
| Bastion Business Limited | Health & social care | 2021 |
| Batemans Management Company Limited | Real estate | 1997 |
| Battery Recyclers Ltd | Water & waste | 2014 |
| Bay Tree Consultants Ltd | Construction | 2011 |
| BB Neuroscience Ltd | Professional & scientific | 2024 |
| Bbq's & Beyond Limited | Wholesale & retail | 2024 |
| BDR Racing Ltd | Arts & recreation | 2025 |
| Beach Road Botanist Ltd | Households | 2026 |
| Beacon Travel Service Worldchoice Ltd | Administrative & support | 2012 |
| Beacon Tyres & MOT Ltd | Wholesale & retail | 2026 |