| Biowood Recycling Limited | Water & waste | 2012 |
| Birchley Estates Limited | Real estate | 2020 |
| Birdweb Limited | Professional & scientific | 2018 |
| Birmingham and Midlands Plumbing and Drainage Limited | Construction | 2017 |
| Birmingham AV Ltd | Wholesale & retail | 2020 |
| Birmingham Bonder Ltd | Health & social care | 2026 |
| Birmingham Building Contractors Limited | Construction | 2014 |
| Birmingham Case Makers Limited | Manufacturing | 2012 |
| Birmingham Hand Surgery Ltd | Health & social care | 2019 |
| Birmingham Osteopathy Ltd | Health & social care | 2019 |
| Birmingham Road Ltd | Hospitality | 2025 |
| Birmingham Road Utilities Ltd | Real estate | 2025 |
| Birmingham Security Management Company Limited | Administrative & support | 2021 |
| Birmingham Student House Ltd | Real estate | 2016 |
| Bismillah Building Ltd | Real estate | 2025 |
| BIT Monkey Ltd | Information & communication | 2026 |
| Bizmiella Ltd | Wholesale & retail | 2021 |
| BL Electrical Solutions Ltd | Construction | 2026 |
| BL Racing Ltd | Arts & recreation | 2024 |
| Black Country Coaches Club CIC | Education | 2020 |
| Black Country Gymnastics Ltd | Arts & recreation | 2025 |
| Black Country Homes Ltd | Real estate | 2026 |
| Black Country Innovation and Technology Ltd | Information & communication | 2026 |
| Black Dog Safety Ltd | Administrative & support | 2015 |
| Black Pear Weaving Limited | Manufacturing | 2025 |
| Black Penny Group Services Limited | Construction | 2021 |
| Black Rabbit Autos Ltd | Wholesale & retail | 2026 |
| Black Street Retail Ltd | Wholesale & retail | 2026 |
| Blackberry Events Ltd | Administrative & support | 2011 |
| Blackmere Holdings Limited | Professional & scientific | 2025 |
| Blackpark Estates Limited | Construction | 2025 |
| Blackrock Property Solutions Ltd | Households | 2024 |
| Blackstar OIL Corporation Ltd | Transport & logistics | 2025 |
| Blackstar VAT Services Limited | Professional & scientific | 2009 |
| Blackwell Adventure | Arts & recreation | 1980 |
| Blackwell Community Hall CIC | Other services | 2021 |
| Blackwell Golf Club,Limited | Arts & recreation | 1922 |
| Blair Property Management Ltd | Real estate | 2021 |
| Blaker Property Development Ltd | Real estate | 2023 |
| Bliss RAE & Company Limited | Information & communication | 2014 |
| Blitzx Solutions Ltd | Professional & scientific | 2025 |
| Bloody Vapes Limited | Wholesale & retail | 2023 |
| Bloom Brand Limited | Wholesale & retail | 2026 |
| Bloom Maternity Ltd | Health & social care | 2026 |
| Bloomhaus Limited | Wholesale & retail | 2026 |
| Bloomsbury Family and Forensic Psychology Ltd | Health & social care | 2024 |
| Blossom Care Properties Limited | Financial services | 2017 |
| Blue Book Holdings Limited | Financial services | 2025 |
| Blue Dog Property 3 Limited | Real estate | 2015 |
| Blue Dog Property Ltd | Real estate | 2012 |
| Blue DOT Quantity Surveying Ltd | Professional & scientific | 2023 |
| Blue Flamingo Creative Solutions Limited | Manufacturing | 2018 |
| Blue Frog Construction Limited | Construction | 2026 |
| Blue Giraffe Childcare (Bromsgrove) Limited | Wholesale & retail | 2014 |
| Blue Lagoon Heritage Ltd | Extraterritorial | 2010 |
| Blue Marlin Trucking Limited | Transport & logistics | 2020 |
| Blue Stag Technologies Limited | Other services | 2016 |
| Blue Text Limited | Hospitality | 2018 |
| Blue Wolf Estates Ltd | Real estate | 2026 |
| Blueberry Windows & Conservatories Ltd | Construction | 2008 |
| Bluechip CNC Limited | Manufacturing | 2009 |
| Bluemoon Technologies Limited | Information & communication | 2022 |
| Blueprint CDM Ltd | Professional & scientific | 2023 |
| Blueprint Vision Ltd | Information & communication | 2025 |
| Bluevolution Limited | Other services | 2021 |
| Bluewater International LLP | | 2020 |
| Bluewaters Canine Centre Ltd | Other services | 2018 |
| Bluewood Management Limited | Arts & recreation | 2024 |
| Blugu Ltd | Information & communication | 2006 |
| Blushome Limited | Administrative & support | 2018 |
| Blythswood Limited | Professional & scientific | 1996 |
| BOB Biomechanics Limited | Professional & scientific | 2016 |
| Bodenium Ltd | Professional & scientific | 2020 |
| Body & Soul Well Being Ltd | Other services | 2007 |
| Body Shop Limited (the) | Real estate | 1969 |
| Boldcraft Limited | Energy | 1991 |
| Bollands Accountants Limited | Professional & scientific | 2011 |
| Boltspire Limited | Wholesale & retail | 2026 |
| Bona Law Limited | Administrative & support | 2010 |
| Bonds Studios Ltd | Wholesale & retail | 2023 |
| Bonnie Dog Productions Limited | Arts & recreation | 2026 |
| Bonzo and Sons Limited | Professional & scientific | 2021 |
| BOO MM Limited | Financial services | 2013 |
| Boom Films Limited | Information & communication | 2016 |
| Boot Stays Ltd | Real estate | 2024 |
| Boot Surveying Services Limited | Professional & scientific | 2016 |
| Boss Group Homes Ltd | Real estate | 2023 |
| Bossvark Consulting Ltd | Public administration | 2023 |
| Bosworth Cladding Services Limited | Construction | 2026 |
| BOT Solutions 1 Ltd | Education | 2025 |
| Both/And Productions Limited | Arts & recreation | 2019 |
| Boulevard Bromsgrove Management Company Ltd | Construction | 2026 |
| Bound Four Limited | Information & communication | 2025 |
| Boundless - Artful Wellbeing CIC | Health & social care | 2025 |
| Bournescaffoldingservices Ltd | Construction | 2022 |
| Bowen Landscape Management Ltd | Agriculture & fishing | 2019 |
| Box Positive C.I.C. | Arts & recreation | 2018 |
| Boxer Facilities Management Ltd | Administrative & support | 2010 |
| Boxer Group Services Limited | Administrative & support | 2022 |
| Bracadale Limited | Real estate | 1976 |