| Benny's Diner (Long Sutton) Ltd | Hospitality | 2013 |
| Bensley Leake Limited | Real estate | 2025 |
| Bentley Builders Norfolk Limited | Construction | 2025 |
| Beresford & Cornwell Holdings Limited | Real estate | 2025 |
| Bermia Ltd | Hospitality | 2026 |
| Berry Brook Properties Ltd | Real estate | 2016 |
| Berrywood Homes Limited | Construction | 2020 |
| Besmart Pro Ltd | Wholesale & retail | 2024 |
| Bespak Europe Limited | Manufacturing | 1998 |
| Bespoke Construction Group Limited | Construction | 2024 |
| Bespoke Development Group Limited | Construction | 2025 |
| Bespoke Estate Group Ltd | Real estate | 2017 |
| Bespoke Harpley Limited | Construction | 2025 |
| Bespoke Hillington Limited | Real estate | 2025 |
| Bespoke Holdings Group Limited | Real estate | 2024 |
| Bespoke Norfolk (Heacham Hall) Limited | Construction | 2023 |
| Bespoke Norfolk Group Limited | Construction | 2018 |
| Bespoke Royston Limited | Construction | 2025 |
| Bespoke Rudham Limited | Construction | 2025 |
| Bespoke Stables and Barns Limited | Manufacturing | 2025 |
| Best at Bars Limited | Hospitality | 2019 |
| Best Palliative Care Services Limited | Health & social care | 2025 |
| Bestneutral Limited | Administrative & support | 1986 |
| Beyleveld Timber Limited | Wholesale & retail | 1995 |
| Beyond the Meadow Limited | Other services | 2021 |
| BGR Vision Limited | Extraterritorial | 2019 |
| Biasbiasbiasbias Limited | Manufacturing | 2023 |
| Big Bang Hire Ltd | Administrative & support | 2026 |
| Bijan Beigi Limited | Health & social care | 2018 |
| Bimble on the Bike Tours Limited | Administrative & support | 2019 |
| Bino Education Limited | Administrative & support | 2017 |
| Biobridge Energy Limited | Extraterritorial | 2026 |
| Bioguardserviceskl Ltd | Administrative & support | 2026 |
| Biokinect Limited | Professional & scientific | 2012 |
| Bioprinter Limited | Information & communication | 2010 |
| Bircham Trees and Landscapes Ltd | Other services | 2013 |
| Bishop's Taxis Limited | Transport & logistics | 2025 |
| Bisquid Promach Ltd | Manufacturing | 2025 |
| Bitsons Ltd. | Hospitality | 2002 |
| BJA Ltd | Financial services | 2022 |
| Black and Organ Motorsports Limited | Arts & recreation | 2025 |
| Black Galleon Ltd | Other services | 2014 |
| Black OWL Ltd | Real estate | 2021 |
| Blackborough END Equestrian Centre LLP | | 2013 |
| Blackfriars Court Limited | Financial services | 2016 |
| Blackfriars Residents Limited | Households | 2007 |
| Blackwell Optimus Ventures Ltd | Professional & scientific | 2026 |
| Blades UK Ltd | Construction | 2003 |
| Blakeney House Ltd. | Hospitality | 2015 |
| Blaze Building and Maintenance Limited | Construction | 2020 |
| Blindcrow Ltd | Information & communication | 2025 |
| BLL Property Group Ltd | Real estate | 2026 |
| Blockprime Residents Management Limited | Households | 1988 |
| Blsg COE Limited | Financial services | 2018 |
| Bluacre Ltd | Construction | 2021 |
| Blue FIN Consultants Ltd | Professional & scientific | 1999 |
| Blue Sky Contracts Limited | Financial services | 2014 |
| Blue Wolf D&C Ltd | Professional & scientific | 2019 |
| Bluebell Cleaning Services Limited | Administrative & support | 2018 |
| Bluebell Support Services Limited | Health & social care | 2015 |
| Bluekite Advisors Ltd | Professional & scientific | 2024 |
| Bluestonedirect Ltd | Wholesale & retail | 2007 |
| BM01BALAN Ltd | Transport & logistics | 2023 |
| BMD Property Investments Ltd | Construction | 2024 |
| BMF Inc Limited | Real estate | 2011 |
| BMR Piling and Foundations Ltd | Construction | 2023 |
| Bnbs Catering Limited | Administrative & support | 2009 |
| BNU Rodna Stryaha - King's Lynn Ltd | Education | 2024 |
| BOA Services Limited | Health & social care | 2016 |
| Bobbetts Property Services Ltd | Construction | 2025 |
| Bobby Hills Limited | Construction | 2021 |
| Bokhara Investments Limited | Financial services | 2024 |
| Bolmeer Limited | Real estate | 2010 |
| Bolt Industrial Engineering Services Limited | Professional & scientific | 2017 |
| Bonza Settle Limited | Professional & scientific | 2007 |
| Book and Go Holidays Ltd | Administrative & support | 2019 |
| Booklife Publishing Limited | Wholesale & retail | 2018 |
| Bookmark Spalding Limited | Wholesale & retail | 2002 |
| Borodex Limited | Real estate | 1984 |
| Boss Barber Studio Ltd | Other services | 2025 |
| Botanic Spaces Limited | Wholesale & retail | 2025 |
| Boucle Boutique Limited | Wholesale & retail | 2023 |
| BOW Brand International Limited | Manufacturing | 1995 |
| BOW Brand Strings Limited | Manufacturing | 2024 |
| Bowes-Vergette Limited | Real estate | 2017 |
| Boxrec Ltd | Other services | 2018 |
| BPH Plumbing and Heating Norfolk Limited | Construction | 2017 |
| BPM Norfolk Limited | Construction | 2013 |
| BPT Retail Services Ltd | Professional & scientific | 2013 |
| Brackenbury Plastering Ltd | Construction | 2026 |
| Bradley Engineering Ltd | Professional & scientific | 2017 |
| Bradshaw & Co Norfolk Ltd | Hospitality | 2026 |
| Bramble Diagnostics Limited | Health & social care | 2025 |
| Brancaster Bay Shellfish Limited | Extraterritorial | 2012 |
| Brancaster Drinks Limited | Wholesale & retail | 2023 |
| Brancaster Garage Limited | Wholesale & retail | 2006 |
| Bravo Builders and Maintenance Ltd | Construction | 2012 |
| Braybrook & Britten Limited | Wholesale & retail | 1995 |
| Breakfast and Brunch Limited | Hospitality | 2025 |
| Breckland & Hall Limited | Financial services | 2019 |