| Belle Toute Lighthouse Company Ltd | Hospitality | 2008 |
| Belmont Services Club Ltd | Hospitality | 2025 |
| Bennetts Pet Foods Limited | Manufacturing | 1980 |
| Bentley Fields Residents Management Company Limited | Households | 2019 |
| Benzi Construct Limited | Construction | 2021 |
| Bernerwoulds Ltd | Health & social care | 2026 |
| Bessel Studio Lighting Limited | Wholesale & retail | 2010 |
| Best Investment Holdings Ltd | Real estate | 2025 |
| Best-Chem Limited | Extraterritorial | 1999 |
| Bethany Iris Beauty Ltd | Other services | 2026 |
| Bevan Industries Limited | Other services | 2022 |
| Beyond Shelter UK Community Interest Company | Hospitality | 2025 |
| Bfrx Ltd | Wholesale & retail | 2025 |
| BGH Plumbing and Heating Ltd | Construction | 2019 |
| Bicester Residents Management Company Limited | Households | 2017 |
| Big Adventures Theatre Company Limited | Arts & recreation | 2000 |
| Big Fish Takeaway Limited | Hospitality | 2015 |
| Biml Limited | Hospitality | 2024 |
| Biophilic Construction UK Limited | Construction | 2025 |
| Bippity Boppity BOO Cleans Limited | Administrative & support | 2023 |
| Birch FIX Limited | Construction | 2017 |
| Birches View (South Wingfield) Residents Management Company Limited | Households | 2022 |
| Biri Ltd | Transport & logistics | 2018 |
| Bishops Bars Ltd | Hospitality | 2024 |
| Bismts Limited | Wholesale & retail | 2025 |
| Bissell Holdings Ltd | Financial services | 2021 |
| BK Coding Ltd | Professional & scientific | 2025 |
| BKB (Bathroom Kitchen Boiler) Installations Ltd | Construction | 2025 |
| Black Caviar Club Ltd | Hospitality | 2020 |
| Black Heart Entertainment Ltd | Arts & recreation | 2025 |
| Blackfordby Barns Limited | Households | 2020 |
| Blackfordby Inns Ltd | Real estate | 2013 |
| Blackham Gardens (Boldmere) Management Company Limited | Households | 2023 |
| Blackstairs Property Ltd | Real estate | 2023 |
| Blackwood Leisure Vehicles Limited | Wholesale & retail | 2004 |
| Blaengwawr Management Company Limited | Households | 2023 |
| Blakes Bistro and Wine Bar Ltd | Hospitality | 2025 |
| Blaze Fire and Security Limited | Construction | 2023 |
| Bleaklow Holdings Limited | Financial services | 2021 |
| Bliss Professional Services Limited | Professional & scientific | 2025 |
| Block 3 Ltd | Information & communication | 2016 |
| Bloomfield Capital Ltd | Professional & scientific | 2026 |
| Bloomfield Holdings Ltd | Financial services | 2026 |
| Bloomin Cards Ltd | Manufacturing | 2022 |
| Bloomline Limited | Wholesale & retail | 2025 |
| Bloor Engineering Ltd | Professional & scientific | 2022 |
| Bloor Holdings Limited | Construction | 1986 |
| Bloor Homes Limited | Construction | 1987 |
| Bloor Investments Limited | Professional & scientific | 2012 |
| Bloor Potteries Limited | Manufacturing | 1993 |
| Bloor's Private Hire Limited | Extraterritorial | 2003 |
| Blossom Oils Ltd | Manufacturing | 2017 |
| Blue Oak Rural Contracting Limited | Agriculture & fishing | 2025 |
| Blue Pill Consulting Ltd | Information & communication | 2015 |
| Blue Skies Care Group Ltd | Health & social care | 2023 |
| Blue Tuesday Ltd | Administrative & support | 2016 |
| Bluebell Meadows (Netherthong) Management Company Limited | Households | 2024 |
| Blueberry Breaks Limited | Real estate | 2025 |
| Blueberry Group Ltd | Wholesale & retail | 2025 |
| Bluedog Employment Services Ltd | Administrative & support | 2026 |
| Blueglove Cleaning Service Ltd | Administrative & support | 2025 |
| Bluemark Projects (Kenilworth) Limited | Construction | 2011 |
| Bluemark Projects Limited | Construction | 2009 |
| BOA Motors Ltd | Wholesale & retail | 2024 |
| Board Buddies Ltd | Administrative & support | 2026 |
| Boardman Industrial Estate Management Company Limited(The) | Construction | 1983 |
| Bombay Spice Restaurant Limited | Hospitality | 2014 |
| Bond’S Accountancy Limited | Professional & scientific | 2024 |
| Bonneville Limited | Professional & scientific | 1988 |
| Bonte Limited | Wholesale & retail | 2023 |
| Bookkeeping & Accounts Ltd | Professional & scientific | 2025 |
| Bookkeeping Connect Limited | Professional & scientific | 2007 |
| BOP Safety Associates Ltd | Professional & scientific | 2023 |
| Bora Solutions Ltd | Public administration | 2019 |
| Borne Overland Limited | Wholesale & retail | 2019 |
| Bosveld Services Limited | Mining & quarrying | 2013 |
| Bouncy Days Ltd | Arts & recreation | 2025 |
| Boundary Carpets & Flooring Limited | Construction | 2017 |
| Bozdogan&Wilson Global Ltd | Wholesale & retail | 2025 |
| Brackenfield View (Wessington) Management Company Limited | Households | 2020 |
| Bradcare Limited | Other services | 2007 |
| Braddan House Management Limited | Households | 2007 |
| Bradsit Delivery Limited | Information & communication | 2025 |
| Bramble Wood Day Nursery Ltd | Health & social care | 2018 |
| Bramley Fields (Southwell) Management Company Limited | Households | 2025 |
| Bransford Green Residents Management Company Limited | Households | 2018 |
| Branston ROW Limited | Households | 2014 |
| Bredenley Investment Holdings Limited | Professional & scientific | 1978 |
| Brett Holdings Ltd | Financial services | 2024 |
| BRI Developments Ltd | Construction | 2023 |
| BRI Quantity Surveying Ltd | Professional & scientific | 2023 |
| Brickyard Court Management Company Limited | Households | 2005 |
| Bridge View (Wheaton Aston) Management Company Limited | Households | 2022 |
| Bridgefoot Developments Limited | Health & social care | 2006 |
| Bridges Developments Limited | Construction | 2009 |
| Bridle Meadows (Luddington) Management Company Limited | Households | 2021 |
| Bright Side Partnership Limited | Professional & scientific | 2017 |
| Bring ME My Motor Ltd | Transport & logistics | 2026 |
| Brizelea Investment Holdings Limited | Professional & scientific | 1978 |
| Brooks Garage (Castle Gresley) Limited | Wholesale & retail | 1964 |