| Apex Woodland & Wildlife Services Ltd | Agriculture & fishing | 2023 |
| Apoko Ltd | Wholesale & retail | 2021 |
| App Innovate Limited | Information & communication | 2013 |
| Applied Business Reviews Ltd | Professional & scientific | 2022 |
| Aqueous Pro Ltd | Professional & scientific | 2024 |
| Aquila Films Ltd. | Information & communication | 1997 |
| Aquila GVS Limited | Administrative & support | 2021 |
| Arandur Accounting Limited | Professional & scientific | 2013 |
| Arborweald Limited | Construction | 2025 |
| ARC Specialist Services Ltd | Administrative & support | 2015 |
| Arcglade Services Limited | Wholesale & retail | 1990 |
| Archivision Ltd | Professional & scientific | 2022 |
| Archway South Construction Limited | Construction | 2025 |
| Aren Homes Ltd | Construction | 2023 |
| Ariel Dynamic Carriers Limited | Transport & logistics | 2023 |
| Arion Consulting Group Limited | Information & communication | 2026 |
| Aroonvale Limited | Households | 1984 |
| Art Resilience Consulting Ltd | Professional & scientific | 2021 |
| Artelier Limited | Arts & recreation | 2007 |
| Arya Court (Eastbourne) Limited | Households | 1986 |
| Arzent Ltd | Information & communication | 2015 |
| AS Bene Ltd | Real estate | 2026 |
| ASA Medcare Limited | Health & social care | 2000 |
| Ascension Cider Co. Limited | Manufacturing | 2017 |
| Asian Middle East Restaurants Ltd | Professional & scientific | 2013 |
| ASPLAN9 Ltd | Wholesale & retail | 2017 |
| Astral Recruitment Limited | Administrative & support | 2007 |
| Atlas 25 Bidco Limited | Financial services | 2025 |
| Atlas 25 Midco 1 Limited | Financial services | 2025 |
| Atlas 25 Midco 2 Limited | Financial services | 2025 |
| Atlas 25 Topco Limited | Financial services | 2025 |
| Aughrim Consultancy Ltd | Administrative & support | 2019 |
| AUP Group Limited | Financial services | 2022 |
| AUP Homes Limited | Real estate | 2022 |
| Auronn Limited | Information & communication | 2022 |
| Autokorrect Ltd | Wholesale & retail | 2024 |
| Avdv Consulting Limited | Administrative & support | 2013 |
| Avenues One Ltd | Other services | 2019 |
| AVF Planning and Design Ltd | Professional & scientific | 2024 |
| AW Spectrum Ltd | Construction | 2021 |
| AWT Eastbourne Ltd | Transport & logistics | 2024 |
| Axis Draughting Solutions Limited | Other services | 2005 |
| Ayus Law Ltd | Professional & scientific | 2025 |
| AZO South East Limited | Hospitality | 2025 |
| B Honey Consulting Ltd | Professional & scientific | 2025 |
| B N Construction UK Limited | Extraterritorial | 2009 |
| BAB Property Ltd | Real estate | 2024 |
| Badygi Limited | Wholesale & retail | 2023 |
| Bargrove RTM Company Limited | Households | 2004 |
| Baro Capital Limited | Financial services | 2023 |
| Barry Technology Ltd | Information & communication | 2013 |
| Battle Groundworks Ltd | Construction | 2025 |
| Battle Landscapes Ltd | Administrative & support | 2022 |
| Baxter Buildings (Eastbourne) LLP | | 2021 |
| BBG Commercial Property Limited | Administrative & support | 2016 |
| BC Developments South East Ltd | Construction | 2012 |
| BC Property South East Ltd | Construction | 2012 |
| Bcqs Ltd | Professional & scientific | 2017 |
| BDE and Co Limited | Financial services | 2025 |
| BDM Plumbing and Heating Ltd | Construction | 2022 |
| BE Pretty Tanned Ltd | Other services | 2025 |
| Beachside Holiday Rentals Ltd | Real estate | 2018 |
| Beachside Holidays Limited | Hospitality | 2023 |
| Beachside Property Sales Ltd | Real estate | 2019 |
| Beachy Head Press Limited | Information & communication | 2020 |
| Bearded Bros Limited | Transport & logistics | 2019 |
| Beauport Building Services Ltd | Construction | 2022 |
| Beautiful Backs Ltd | Wholesale & retail | 2008 |
| Beeches Property Limited | Professional & scientific | 1974 |
| Beechtobeach Ltd | Information & communication | 2012 |
| Beezra Ltd | Other services | 2021 |
| Belfast Professional Accommodation Ltd | Hospitality | 2023 |
| Bella Napoli (East Sussex) Limited | Hospitality | 2020 |
| Belminster Management Limited | Real estate | 2003 |
| Belovd Group Ltd | Professional & scientific | 2025 |
| BEN Westwood Music Ltd | Information & communication | 2026 |
| Benrub Limited | Professional & scientific | 2016 |
| Beormund Limited | Information & communication | 2007 |
| Bernhard Baron Care Home | Health & social care | 1998 |
| Berwick Service Station Limited | Wholesale & retail | 2004 |
| Besent 2 Limited | Real estate | 2003 |
| Besent Limited | Real estate | 2003 |
| Bespoke Handmade Ltd | Manufacturing | 2022 |
| Bespoke Trades Ltd. | Construction | 2011 |
| Beverley Electrical Ltd | Construction | 2015 |
| Beyers Brickwork Limited | Construction | 2020 |
| BF Platforms Ltd | Information & communication | 2026 |
| BGB Commerce Ltd | Manufacturing | 2020 |
| BGM Clubs Limited | Hospitality | 2026 |
| Bickers Bricks Ltd | Wholesale & retail | 2026 |
| Big Kahunas Limited | Wholesale & retail | 2007 |
| Big Sky Project Management Ltd | Professional & scientific | 2021 |
| Bigg-In Words Ltd | Extraterritorial | 2007 |
| BIO Nutrition Health Products Limited | Wholesale & retail | 1988 |
| Bismuth Works Ltd | Information & communication | 2020 |
| Bixi Consulting Limited | Professional & scientific | 2026 |
| Black Opal Supply Solutions Ltd | Professional & scientific | 2019 |
| Blackmetric Business Solutions Limited | Administrative & support | 2012 |
| Blackmore Business Solutions Ltd | Other services | 2022 |
| Blake Trade Ltd | Wholesale & retail | 2023 |