| Bentley Programme Controls Limited | Other services | 2017 |
| Bentoni Holdings Ltd | Administrative & support | 2025 |
| Berkeley Swiss Ltd | Real estate | 2018 |
| BEST4 Group Limited | Wholesale & retail | 2001 |
| BEST4 UK Ltd | Wholesale & retail | 2021 |
| BEST4VAPES Ltd | Wholesale & retail | 2021 |
| Bestfostering Ltd | Health & social care | 2025 |
| Beyond OUR Kingdom Ltd | Wholesale & retail | 2021 |
| Beyti Limited | Hospitality | 2025 |
| BFC Properties Ltd | Construction | 2023 |
| BGN DRY Ice Blasting Ltd | Administrative & support | 2025 |
| Big Cat Limited | Professional & scientific | 2014 |
| Big Tele Ltd | Information & communication | 2022 |
| Big Wave Sourcing Ltd | Wholesale & retail | 2016 |
| Bignosefoods Ltd | Manufacturing | 2020 |
| Bigtel Ltd | Information & communication | 2025 |
| BIN Washed Ltd | Administrative & support | 2020 |
| Bioworld International Limited | Manufacturing | 2014 |
| Birch & Berry Limited | Real estate | 2023 |
| Biskel Properties Ltd | Real estate | 2026 |
| Bisla Property Services Limited | Real estate | 2009 |
| Bison Investments Limited | Financial services | 2019 |
| Bixhill Properties Limited | Real estate | 2026 |
| Bizzing Limited | Information & communication | 2010 |
| BK Nova Ltd | Wholesale & retail | 2026 |
| BKM Design Services Ltd | Manufacturing | 2010 |
| Blackwell Refurbishment Ltd | Real estate | 2024 |
| Blaine Smith Limited | Construction | 2003 |
| Blakemore Properties Limited | Real estate | 2021 |
| Blare Enterprises Ltd | Information & communication | 2023 |
| Blissy Cleaning Services Ltd | Real estate | 2024 |
| Blitz Mark Ltd | Transport & logistics | 2015 |
| Blockside Properties Ltd | Real estate | 2001 |
| Blooming Lovely Ltd | Other services | 2023 |
| Blue Angle Properties Limited | Real estate | 2021 |
| Blue Apex Limited | Transport & logistics | 2006 |
| Blue EYE Vision Limited | Information & communication | 2009 |
| Blue Sky Estate Agents Limited | Real estate | 2024 |
| Blue Wolf Planning Ltd | Construction | 2020 |
| Blum Decals Limited | Wholesale & retail | 2025 |
| BOB Eaton Studio Ltd | Arts & recreation | 2025 |
| BOB Jackson & SON Ltd | Construction | 2011 |
| Bokoroko Limited | Extraterritorial | 2024 |
| Bold Soul Services Limited | Health & social care | 2021 |
| Bolster Lifestyle Ltd | Manufacturing | 2023 |
| Bond Engineering (Turned Parts) Limited | Manufacturing | 1984 |
| Bond Street Distillery Ltd. | Manufacturing | 2017 |
| Bond Street Garage Ltd | Wholesale & retail | 2024 |
| Bond Street Trophies Limited | Administrative & support | 2007 |
| Bondestin Solutions Ltd | Financial services | 2026 |
| Boode U.K. Limited | Construction | 1989 |
| Bora Maintenance Limited | Professional & scientific | 2018 |
| Boreal Tree Care & Environmental Ltd | Professional & scientific | 2023 |
| Bosanco Ltd | Transport & logistics | 2014 |
| Bosworth Plastics Limited | Manufacturing | 1997 |
| Botany Bay Garden Services Ltd | Administrative & support | 2025 |
| Boulton Moor (Derby) Management Company Limited | Households | 2016 |
| Bowood Care Homes Limited | Health & social care | 2014 |
| Boyslade Garage Limited | Wholesale & retail | 2007 |
| BP Auto Sales and Recovery Ltd | Wholesale & retail | 2021 |
| BR Electrical Controls Ltd | Manufacturing | 2009 |
| Bradgate Park (Hinckley) Management Company Limited | Households | 2006 |
| Bradley Ellis Racing Limited | Other services | 2014 |
| Bradwards Limited | Wholesale & retail | 2002 |
| Brake Pipe Flaring Tools Limited | Manufacturing | 2010 |
| Brambles Vintage Interiors Limited | Wholesale & retail | 2019 |
| Brand New Glasses Limited | Wholesale & retail | 2013 |
| BRAND786 Ltd | Information & communication | 2012 |
| Brave Lynx Limited | Professional & scientific | 2025 |
| Bravo Holdings Limited | Real estate | 2016 |
| Brayon Limited | Manufacturing | 2017 |
| Brealey Foster & Co Limited | Professional & scientific | 2022 |
| Brian List Plumbing & Heating Limited | Construction | 2017 |
| Brick & Stone Ltd | Other services | 2026 |
| Bricknell Enterprises Limited | Financial services | 2022 |
| Briggs Hillier Design Limited | Professional & scientific | 2000 |
| Brindley Lift Truck Services Limited | Administrative & support | 1978 |
| Brio Media Ltd | Extraterritorial | 2018 |
| Broadoak RTM Company Limited | Households | 2016 |
| Brockhouse Property Maintenance Limited | Construction | 2010 |
| Bromwich Decorating Services Ltd | Construction | 2025 |
| Brook Precision Ltd | Manufacturing | 2014 |
| Brookbern (Contracts) Limited | | 1982 |
| Brookfield Signs & Graphics Limited | Manufacturing | 2000 |
| Brookhill Farm (Barwell) Limited | Agriculture & fishing | 2010 |
| Brookstone Creative Ltd | Information & communication | 2015 |
| Brookvale Limited | Professional & scientific | 1983 |
| Bropam Limited | Wholesale & retail | 2005 |
| Browns Health and Safety Limited | Administrative & support | 2024 |
| BRU Y Rubio (UK) Limited | Wholesale & retail | 2010 |
| Bruntwood Europe Ltd | Real estate | 2003 |
| Brythan House Limited | Education | 2017 |
| BSE Logistics Ltd | Transport & logistics | 2025 |
| Btuk Accommodation Limited | Hospitality | 2018 |
| Btuk Productions Limited | Professional & scientific | 2018 |
| Bubble Finance Hub Limited | Financial services | 2019 |
| Bubbles Active Play and Blue Bubbles Pre-School Limited | Other services | 2015 |
| Buildersbrew Ltd | Manufacturing | 2022 |
| Building Control Training Academy Ltd | Education | 2016 |
| Bulls Head Freehouse Stoney Stanton Limited | Hospitality | 2017 |