| Balmoral Homes Limited | Construction | 2002 |
| Balmoral Property Services Ltd | Other services | 2010 |
| Balmoral Technology Group Ltd | Information & communication | 2016 |
| Balo Services Ltd | Arts & recreation | 2024 |
| BAM Consulting Ltd | Information & communication | 2011 |
| Bamboo Beat Media Ltd | Information & communication | 2017 |
| Bambooco Ltd | Wholesale & retail | 2019 |
| Bamsee MC Tech Ltd | Wholesale & retail | 2018 |
| Banks Roofing Ltd | Construction | 2020 |
| Barber Investments Limited | Financial services | 2022 |
| Barber Papa Ltd | Other services | 2019 |
| Barbers of Send Ltd | Other services | 2023 |
| Barham Services Limited | Professional & scientific | 1992 |
| Barkable Ltd | Wholesale & retail | 2021 |
| Barn Autors Ltd | Wholesale & retail | 2023 |
| Barn Door Asset Management Limited | Real estate | 2018 |
| Barnabas Coaching & Training Ltd | Professional & scientific | 2017 |
| Barnbrook Sinclair Limited | Professional & scientific | 1998 |
| Barnes Fitness Limited | Arts & recreation | 2013 |
| Barnfather Communications Limited | Professional & scientific | 2011 |
| Barns Fields Limited | Other services | 2014 |
| Barratt Moran Ltd | Real estate | 2024 |
| Barry Quinn Ltd | Administrative & support | 2016 |
| Barsc Ltd | Other services | 2021 |
| Barselona Limited | Health & social care | 2005 |
| Bartek Builders Ltd | Construction | 2011 |
| Bartlet Bidco Limited | Manufacturing | 2017 |
| Basaar EU Ltd | Wholesale & retail | 2025 |
| Basalt Construction Solutions Ltd | Wholesale & retail | 2024 |
| Baseltech UK Ltd | Professional & scientific | 2015 |
| Basing Rental Ltd | Real estate | 2019 |
| Basinghall Analytics Ltd | Professional & scientific | 2019 |
| Basinghall Holdings Ltd | Financial services | 2022 |
| Basingstoke Heating and Plumbing Supplies Limited | Wholesale & retail | 2019 |
| Basnah Limited | Wholesale & retail | 2014 |
| Bassetti Ltd | Construction | 2018 |
| BAT OUT of Hell Holdings Limited | Administrative & support | 2007 |
| Bates Estates Group Ltd | Real estate | 2022 |
| Batista Handyman Service Ltd | Manufacturing | 2024 |
| Baurest Ltd | Construction | 2020 |
| Bavex Holdings Limited | Financial services | 2017 |
| Bayanii Limited | Wholesale & retail | 2024 |
| BB Foods UK Ltd | Wholesale & retail | 2009 |
| BBF Fielding Limited | Professional & scientific | 1989 |
| BBK Finance Ltd | Professional & scientific | 2015 |
| BBQ & GAS Property Limited | Financial services | 2021 |
| BBQ and GAS Group Limited | Financial services | 2021 |
| BC Plastering Ltd | Construction | 2023 |
| BCM Kapital Ltd | Construction | 2016 |
| BCP Transport Consultants Ltd | Extraterritorial | 2012 |
| BD Business Ltd | Wholesale & retail | 2015 |
| Bdcore Solutions Limited | Information & communication | 2025 |
| BE Confident Group Limited | Education | 2016 |
| BE Disruptive Ltd | Information & communication | 2015 |
| BE Reactive UK Ltd | Wholesale & retail | 2022 |
| BE Tech Secure Ltd | Information & communication | 2023 |
| BE Vision Services Ltd | Professional & scientific | 2018 |
| Beachcourse Limited | Wholesale & retail | 1997 |
| Beacon(Uk) Limited | Construction | 2023 |
| Beam London Ltd | Professional & scientific | 2010 |
| Beamguard Ltd | Wholesale & retail | 2025 |
| Beanberry Coffee Company Ltd | Manufacturing | 2011 |
| Beansprout Company Limited | Financial services | 2019 |
| Bear Smoke Property Venture Limited | Real estate | 2025 |
| Bearmonkey Consulting Limited | Professional & scientific | 2010 |
| Beat Box Tattoo Ltd | Arts & recreation | 2026 |
| Beautiful Spaces, by David Limited | Water & waste | 2021 |
| Bebe Storage Limited | Other services | 2020 |
| Beck & Blaza Design Ltd | Professional & scientific | 2010 |
| Bedrock Computers Limited | Wholesale & retail | 2021 |
| Bedrock Technologies Limited | Information & communication | 2025 |
| BEE IT Ltd | Information & communication | 2014 |
| Beechwoods Court (Crystal Palace) Limited | Households | 2004 |
| Beef King Woking Ltd | Hospitality | 2024 |
| Beefology Limited | Wholesale & retail | 2025 |
| Bees Boys Limited | Arts & recreation | 2015 |
| Bejj Holdings Limited | Real estate | 2023 |
| Belaissa Ltd | Wholesale & retail | 2018 |
| Belam Property Holdings Limited | Real estate | 2025 |
| Beleu Investments Limited | Real estate | 2011 |
| Beliche Limited | Real estate | 2014 |
| Believe Education Limited | Education | 2017 |
| Bella the Butterfly Limited | Education | 2021 |
| Bellasia Ltd | Real estate | 2022 |
| Belle Idee Ltd | Professional & scientific | 2016 |
| Bellibro Limited | Information & communication | 2007 |
| Bellissimo Bites Ltd | Manufacturing | 2025 |
| Bellmaine Project Services Limited | Information & communication | 2012 |
| Bellu Landscape Ltd | Construction | 2019 |
| BEM Coffee Limited | Hospitality | 2016 |
| BEN Jucos Ltd | Transport & logistics | 2025 |
| Benediva Ltd | Manufacturing | 2025 |
| Beniamin Stan Ltd | Construction | 2017 |
| Benlewisholdings Limited | Wholesale & retail | 2026 |
| Bennetts Financial Consulting Limited | Professional & scientific | 2021 |
| Bensusan Management Group Limited | Professional & scientific | 2021 |
| Bentleys Garage Brookwood Limited | Wholesale & retail | 2012 |
| Berenty Limited | Arts & recreation | 1994 |
| Beretta Associates Limited | Professional & scientific | 1988 |
| Berkshire Aviation Services Limited | Arts & recreation | 1975 |