| Blue Circuit IT Solutions Ltd | Information & communication | 2021 |
| Blue Lapis Consulting Limited | Information & communication | 2025 |
| Blue Marble Analytics Ltd | Information & communication | 2026 |
| Blue Moon Property Holdings Limited | Real estate | 2023 |
| Blue Ocean Code Ltd | Information & communication | 2018 |
| Blue Ocean Solutions Ltd | Financial services | 2022 |
| Blue Raspberry Consulting Limited | Information & communication | 2022 |
| Blue Sky Creations Limited | Professional & scientific | 2007 |
| Blue Sky Management Limited | Real estate | 2026 |
| Blue Sphere Space Limited | Professional & scientific | 2019 |
| Blue Walnut Limited | Professional & scientific | 2012 |
| Blue Welly Events Limited | Hospitality | 2016 |
| Bluebrooke Consulting Limited | Information & communication | 2015 |
| Bluenote Digital Ltd | Professional & scientific | 2026 |
| Bluenote Media Ltd | Professional & scientific | 2021 |
| Blueself Ltd | Professional & scientific | 2014 |
| Bluey Limited | Information & communication | 2020 |
| Bluie West Aviation Limited | Professional & scientific | 2020 |
| Blum Consult Ltd | Professional & scientific | 2015 |
| BLW Project Management Ltd | Professional & scientific | 2026 |
| Boaring Ltd | Hospitality | 2020 |
| Boat Sales Limited | Wholesale & retail | 2024 |
| Boboli Digital Ltd | Information & communication | 2016 |
| Bodhial Limited | Health & social care | 2025 |
| Bodymot Systems Limited | Health & social care | 2008 |
| Boiler Call Services Ltd. | Construction | 2015 |
| Boiling Kettle Limited | Information & communication | 2019 |
| BON AMI Ltd. | Construction | 2002 |
| Bonefish Capital Holdings Ltd | Financial services | 2013 |
| Bonefish Capital Ltd | Real estate | 2013 |
| Bonnie's Beauty Spot Limited | Information & communication | 2013 |
| Bonobo Creative Ltd | Professional & scientific | 2015 |
| Booker Construction Ltd | Construction | 2016 |
| Booker Groundworks Ltd | Construction | 2022 |
| Bookkeeping Bureau Accountancy Services Ltd | Professional & scientific | 2012 |
| Boomboxx Ltd | Professional & scientific | 2023 |
| Boomooroo Ltd | Information & communication | 2023 |
| Borg Automation Ltd | Professional & scientific | 2012 |
| Borg Transmissions Ltd | Professional & scientific | 2012 |
| Borgbon Limited | Information & communication | 2008 |
| Borsuk Software Limited | Information & communication | 2017 |
| Bosair Aviation Support Services Limited | Professional & scientific | 2004 |
| Bosley Conway Ltd | Professional & scientific | 2023 |
| Botanalytica Limited | Professional & scientific | 2024 |
| Bothenwood Farm Limited | Agriculture & fishing | 1952 |
| Boult Property Ltd | Real estate | 2020 |
| Bourne Roofing Solutions Ltd | Construction | 2025 |
| Bournemouth Airport Cars Ltd | Transport & logistics | 2026 |
| Bournemouth Passenger Transport Association Limited | Arts & recreation | 1990 |
| Bournemouth Power and Control Services Limited | Manufacturing | 2015 |
| Boutique in a BUS Limited | Wholesale & retail | 2011 |
| Bowden & Sons Property Ltd | Real estate | 2024 |
| Bower Interiors Limited | Professional & scientific | 2021 |
| Bowkett Inn Ltd | Hospitality | 2023 |
| Bowler Ltd | Professional & scientific | 2018 |
| Bown Consulting and Advisory Ltd | Professional & scientific | 2022 |
| Bowood Homes Guildford Ltd | Construction | 2014 |
| Boxcrowd Ltd | Other services | 2022 |
| Boyle Project Management Ltd | Professional & scientific | 2024 |
| BPW Surveys Limited | Professional & scientific | 2023 |
| Brabus-Performance Ltd | Wholesale & retail | 2025 |
| Brackenhill Consulting Services Ltd | Professional & scientific | 2019 |
| Brackers Limited | Financial services | 2018 |
| Bradbury Medical Communications Limited | Professional & scientific | 2026 |
| Bradley Sheppard Racing Ltd | Wholesale & retail | 2023 |
| Bradmore Limited | Real estate | 1999 |
| Branch Training Ltd | Education | 2025 |
| Brand Buzz Limited | Professional & scientific | 2014 |
| Brand Capital Group Limited | Information & communication | 2017 |
| Brand Flakes Limited | Information & communication | 2019 |
| Brandex Retail Ltd | Wholesale & retail | 2020 |
| Branksome Carpets Limited | Wholesale & retail | 2004 |
| Branksome PUB Co Ltd | Hospitality | 2026 |
| Branksome Wood Mansions and Cottage Residents Association Limited | Households | 1994 |
| Bratwurst UK Limited | Hospitality | 2003 |
| Bravo Alpha Solutions Limited | Information & communication | 2021 |
| Bray Consultancy Services Limited | Professional & scientific | 2019 |
| Brct Supply Services Limited | Information & communication | 2017 |
| Breakbeat Ltd. | Information & communication | 2015 |
| Breakthrough Retreats Ltd | Arts & recreation | 2026 |
| Brecknock Court Management Company Limited | Real estate | 1989 |
| Breeze Electrical Contractors Limited | Construction | 2017 |
| Breeze Property Services Limited | Administrative & support | 2022 |
| Brelia Ltd | Professional & scientific | 2023 |
| Brenlet Ltd | Real estate | 2022 |
| Brennecke Ltd | Information & communication | 2025 |
| Brewcodecafe Limited | Information & communication | 2023 |
| Brewed Software Limited | Information & communication | 2023 |
| Brewers Folly Brewery Ltd. | Manufacturing | 2017 |
| Brian Hennessy Ltd. | Agriculture & fishing | 2003 |
| Brick Galleria Ltd | Arts & recreation | 2015 |
| Bricky Limited | Real estate | 2026 |
| Bridge Precision Engineering Limited | Manufacturing | 2003 |
| Bridgesafe Limited | Administrative & support | 2015 |
| Bridgestyle Ltd | Financial services | 2026 |
| Bright Heart Homecare Services Ltd | Health & social care | 2025 |
| Bright Sky Property Limited | Real estate | 2025 |
| Bright Star Consulting Limited | Professional & scientific | 2025 |
| Brightbarn Systems Ltd | Information & communication | 2022 |
| Brighter Commercials Limited | Real estate | 2025 |