| Barker & Jones Property Limited | Real estate | 2018 |
| Barker Street Centre Limited | Arts & recreation | 2020 |
| Barkers Hairdressing Suppliers Limited | Wholesale & retail | 1977 |
| Barking for a Walk Ltd | Wholesale & retail | 2021 |
| Barn OWL Building Limited | Construction | 2025 |
| Barn OWL Properties Limited | Construction | 2015 |
| Barn Productions Limited | Information & communication | 2014 |
| Barnards Coatings Ltd | Manufacturing | 2017 |
| Barnby Grounds Maintenance Ltd | Administrative & support | 2024 |
| Barndeen Investments Limited | Professional & scientific | 2010 |
| Barndeen Restaurants Limited | Professional & scientific | 2010 |
| Barnes Business Ltd | Real estate | 2020 |
| Barnes Law Limited | Agriculture & fishing | 2014 |
| Barnes Marine Units Limited | Manufacturing | 1977 |
| Barnes Property Services Ltd | Construction | 2026 |
| Barnes Rural Finance Ltd | Financial services | 2025 |
| Barnett Builders Ltd | Construction | 2025 |
| Barnett's Cleaning Solutions Ltd | Wholesale & retail | 2021 |
| Barney Consultancy Ltd | Administrative & support | 2018 |
| Barney Murray Music Ltd | Information & communication | 2023 |
| Barnham Broom Golf Club Limited | Hospitality | 1976 |
| Barnham Broom Limited | Professional & scientific | 1986 |
| Barnham Broom Management Company Limited | Administrative & support | 1980 |
| Barnham Broom NC Limited | Financial services | 2024 |
| Barningham Farms,Limited | Agriculture & fishing | 1942 |
| BARNS4BUSINESS Limited | Wholesale & retail | 2002 |
| Barnsley Norse Limited | Other services | 2011 |
| Barnstorm TV Ltd | Information & communication | 2013 |
| Barnwell Print Limited | Manufacturing | 1999 |
| Baronista Ltd | Wholesale & retail | 2025 |
| Barrack Lane & Ivry Street PCN Limited | Health & social care | 2023 |
| Barrack ST Development NR3 Limited | Construction | 2026 |
| Barrack Street Developments Limited | Real estate | 2023 |
| Barracuda Baths Ltd. | Manufacturing | 2016 |
| Barrant Limited | Real estate | 2016 |
| Barratt & Cooke GSI Nominees Limited | Professional & scientific | 1989 |
| Barratt & Cooke Nominees Limited | Professional & scientific | 1978 |
| Barratt & Cooke Trustees Limited | Professional & scientific | 1992 |
| Barrcode Ltd | Information & communication | 2022 |
| Barrelfield Distribution Limited | Professional & scientific | 2003 |
| Barrett Engineering Ltd | Administrative & support | 2015 |
| Barrett's UK and European Removals Ltd | Transport & logistics | 2024 |
| Barrie Seviour Transport Ltd | Transport & logistics | 2014 |
| Barrington Energy International Limited | Other services | 2017 |
| Barrington Energy Limited | Other services | 2021 |
| Barrington Farm Social Enterprise Limited | Extraterritorial | 2011 |
| Barrington Solar Ltd | Construction | 2023 |
| Barrons of Costessey Ltd | Hospitality | 2016 |
| Barrow Breck Ltd | Other services | 2013 |
| Barrow Close Investments Limited | Real estate | 2016 |
| Barrum Homes Limited | Real estate | 2019 |
| Barry Jarvis Limited | Professional & scientific | 2011 |
| Barsham Barns (Norfolk) Limited Liability Partnership | | 2003 |
| Bartco (UK) Limited | Manufacturing | 2013 |
| Bartech Technical Services Limited | Administrative & support | 2008 |
| Barter Hill Consulting Limited | Professional & scientific | 2020 |
| Barter Hill Partnership Limited | Professional & scientific | 2003 |
| Bartholomews (Great Yarmouth) Limited | Wholesale & retail | 2001 |
| Bartlettings Ltd | Real estate | 2014 |
| Barton & Co Estates Ltd | Real estate | 2015 |
| Barton Catering Ltd | Hospitality | 2019 |
| Barton Property Group Limited | Real estate | 2018 |
| Bartram Holdings Limited | Financial services | 2021 |
| Bartram's of Norwich Limited | Real estate | 2024 |
| Barts Tech Ltd | Wholesale & retail | 2025 |
| BAS Accountancy Limited | Professional & scientific | 2026 |
| BAS Training Ltd | Arts & recreation | 2019 |
| Base Building Solutions Limited | Construction | 2013 |
| Basecamp Brews Ltd | Wholesale & retail | 2015 |
| Basecamp Technology Limited | Information & communication | 2024 |
| Based Labs Ltd. | Information & communication | 2023 |
| Basegenic Ltd | Professional & scientific | 2018 |
| Basement Brown Limited | Hospitality | 2012 |
| Basfords Ltd | Manufacturing | 2001 |
| Basha Pharma Ltd | Health & social care | 2022 |
| Basher Watts Racing Syndicates 7 Limited | Arts & recreation | 2025 |
| Basic Packaging Limited | Professional & scientific | 2009 |
| Basically Sound Limited | Wholesale & retail | 2006 |
| Basil Club Ltd | Hospitality | 2023 |
| Basis Current Engineering Ltd | Information & communication | 2017 |
| Basit Property Services Limited | Real estate | 2023 |
| Baskerville Worldwide Sourcing Limited | Professional & scientific | 2010 |
| Baslow Holdings | Financial services | 2024 |
| Bastin Commercial Ltd | Real estate | 2014 |
| Bata Property Limited | Real estate | 2019 |
| Batchelor Electrical Services Ltd | Construction | 2017 |
| Batelle Ltd | Administrative & support | 2020 |
| Bateman Civil Engineering Limited | Extraterritorial | 2009 |
| Bateman Groundworks (Holdings) Limited | Financial services | 2019 |
| Bateman Groundworks Limited | Construction | 1997 |
| Bateman Groundworks Trustees Limited | Financial services | 2025 |
| Batemans Carpets Limited | Wholesale & retail | 2007 |
| Bath Consultancy Ltd | Information & communication | 2025 |
| Bathurst Cooper Ltd | Professional & scientific | 2025 |
| Battersea PIE Station (Covent Garden) Limited | Hospitality | 2009 |
| Battery Minerals Ltd | Manufacturing | 2024 |
| Battle Hospitality Ltd | Hospitality | 2023 |
| Bauer & Cottrell Limited | Professional & scientific | 2006 |
| Baurencly Ltd | Financial services | 2025 |
| Bauwelle Ltd | Manufacturing | 2025 |