| Asthi Limited | Manufacturing | 2025 |
| Astute Business Consultancy Limited | Professional & scientific | 2001 |
| Atelier Masonry Limited | Construction | 2001 |
| ATR Safari UK Ltd | Administrative & support | 2000 |
| Atticus International Limited | Information & communication | 2016 |
| August Recognition Limited | Information & communication | 2015 |
| Austinracing Limited | Manufacturing | 2015 |
| Auto Carmeleon Limited | Manufacturing | 2015 |
| Automated Retail Technologies UK Limited | Hospitality | 2020 |
| Avery Mind Limited | Education | 2016 |
| Avicenna Centre for Chinese Medicine, LLC | | 2009 |
| Avid PLC | Wholesale & retail | 1992 |
| Awlw Consulting Ltd | Professional & scientific | 2019 |
| B & B Sluicing Solutions Ltd | Health & social care | 2011 |
| B-People Group Ltd | Administrative & support | 2017 |
| Back in Motion (Lewes) Ltd | Health & social care | 2014 |
| BAD Omen Records Ltd. | Information & communication | 2013 |
| Baker Events Trading Ltd | Administrative & support | 2025 |
| Bakerbrown Studio Limited | Professional & scientific | 2002 |
| Bakerwell Limited | Professional & scientific | 2016 |
| Balcombe Place Limited | Hospitality | 2017 |
| Baltic Trader Limited | Wholesale & retail | 2003 |
| Bamford Consultancy Limited | Professional & scientific | 2021 |
| Banner Consulting Ltd | Administrative & support | 2006 |
| Barcombe Bonfire Society Limited | Arts & recreation | 1998 |
| Barcombe Landscapes Limited | Administrative & support | 1994 |
| Barcombe Nurseries LLP | | 2021 |
| Bardakhanova Champkins Limited | Professional & scientific | 2018 |
| Barn Stables (Owners) Limited | Households | 1998 |
| Barons Down Company Limited | Real estate | 1981 |
| Barons Down Residents Association Limited | Households | 1965 |
| Barracuda Recordings Limited | Information & communication | 2015 |
| Bartons of Bawtry Limited | Real estate | 1963 |
| Barwells Independent Financial Management Limited | Professional & scientific | 2012 |
| Barwells Wealth Limited | Financial services | 2026 |
| Base Engineering Limited | Professional & scientific | 2021 |
| Bathing Safety Ltd | Wholesale & retail | 2020 |
| Bathing Safety Southern Ltd | Wholesale & retail | 2020 |
| BB Sports Limited | Arts & recreation | 2017 |
| BCR Partners Limited | Professional & scientific | 2025 |
| Beacon Commodities Limited | Wholesale & retail | 2009 |
| Beacon Down Wines Ltd | Manufacturing | 2016 |
| Beacontown Limited | Information & communication | 1981 |
| Beakus Ltd | Information & communication | 2010 |
| Beancounters of Lewes Limited | Professional & scientific | 2015 |
| Bear Bear Ltd | Real estate | 2021 |
| Beasley Boilers Ltd | Construction | 2021 |
| Beau Nails and Beauty Ltd | Other services | 2014 |
| Beauceron Capital Limited | Real estate | 2024 |
| Beautifix Ltd | Other services | 2018 |
| Beautiful Bunting Limited | Arts & recreation | 2008 |
| Bebop Bikes Ltd | Wholesale & retail | 2025 |
| Bedhampton Holdings Limited | Financial services | 1986 |
| Beer Talking Ltd | Administrative & support | 2023 |
| Beja Sussex Limited | Other services | 2024 |
| Bell Lane, Lewes Management Company Limited | Households | 2020 |
| Belle&Co Ltd | Wholesale & retail | 2020 |
| Bellwether Ltd | Professional & scientific | 2025 |
| Belvoy Group Ltd. | Professional & scientific | 2026 |
| BEN Lovejoy Ltd | Arts & recreation | 2007 |
| Bene Film Locations Limited | Information & communication | 2013 |
| Benjafield Holdings Limited | Construction | 2018 |
| Benson Kitchens Ltd | Construction | 2015 |
| Bentley Inns Ltd | Hospitality | 2022 |
| Bentley Miniature Railway Ltd | Arts & recreation | 2013 |
| Bert Tyler Moore Ltd | Arts & recreation | 2011 |
| Bespoke Kitchens Direct Ltd | Manufacturing | 2021 |
| Best Wishes (West Sussex) Limited | Wholesale & retail | 2011 |
| Between Beyond Ltd | Professional & scientific | 2024 |
| Bevingdean Copse Ltd | Households | 2019 |
| Beyond Green Developments Limited | Professional & scientific | 2007 |
| BG Carpentry Ltd | Construction | 2023 |
| Bhbi Digital Consulting Limited | Information & communication | 2020 |
| Big Brand Beds Limited | Wholesale & retail | 2024 |
| Big Draw Golf Clothing Ltd | Wholesale & retail | 2021 |
| Binsted Farms Limited | Agriculture & fishing | 1957 |
| Biodiversity Research Support Ltd | Professional & scientific | 2023 |
| Biodiversity-Net-Gain-Uk Limited | Real estate | 2024 |
| Biographic Books Limited | Information & communication | 2016 |
| Bircan's Fish Bar Ltd | Hospitality | 2025 |
| Bishops Waltham Montessori School Limited | Education | 2010 |
| Bishopstoke Therapeutics Limited | Health & social care | 2024 |
| BJ Equity Partners Ltd | Real estate | 2025 |
| Bjam Ltd | Professional & scientific | 2011 |
| Black and White Academy Ltd | Education | 2026 |
| Black ANT Ltd | Hospitality | 2021 |
| Black Ship Communications Limited | Arts & recreation | 2012 |
| Blackberry Farm (Sussex) Ltd | Agriculture & fishing | 2017 |
| Blackcap Farms Limited | Financial services | 1998 |
| Blackstone Estate Services Ltd | Construction | 2026 |
| Blackwell Estates Ltd | Construction | 2016 |
| Blank Inside. Limited | Arts & recreation | 2013 |
| Blank Productions | Arts & recreation | 2005 |
| Blaxland Productions Ltd | Administrative & support | 2003 |
| Blee Design Limited | Professional & scientific | 2012 |
| Blind Faith Sempre Ltd | Professional & scientific | 2025 |
| Blink KIT Hire Limited | Information & communication | 2018 |
| Block Services Ltd | Professional & scientific | 2001 |
| Blockbusters Contracts Limited | Water & waste | 1994 |
| Blue and Yellow Investments Limited | Financial services | 2025 |