| Barrow Yeoman Investments Ltd | Real estate | 2021 |
| Bartons Yard Limited | Manufacturing | 2023 |
| Baskett Homes Ltd | Real estate | 2024 |
| Bathrooms and Kitchens Fitted for YOU Limited | Construction | 2020 |
| Bathsheba (Suffolk) Limited | Other services | 2018 |
| Bawdsey Radar Trust | Arts & recreation | 2008 |
| Bawztech Ltd | Information & communication | 2014 |
| Baxter and Baxter Official Ltd | Wholesale & retail | 2018 |
| Bay Tree VA Limited | Administrative & support | 2008 |
| Bayfield Electrical Ltd | Construction | 2006 |
| BE Green Energy Ltd | Construction | 2022 |
| BE Group (Engineering) Ltd | Manufacturing | 2013 |
| Bealings Community CIC | Professional & scientific | 2024 |
| Bear Terrain Ltd | Construction | 2019 |
| Beatty Developments (East Anglia) Limited | Financial services | 1984 |
| Becca Cullum-Green Ltd | Professional & scientific | 2023 |
| Beccles Houses Ltd | Real estate | 2022 |
| Bechmann Limited | Information & communication | 1995 |
| Becky Louise Beauty Clinic Ltd | Other services | 2018 |
| Becky's Limited | Wholesale & retail | 2021 |
| BEE Cafe CIC | Administrative & support | 2024 |
| Beer Properties Ltd | Real estate | 2020 |
| Bellissima Beauty Salon Ltd | Other services | 2019 |
| Belltima Limited | Professional & scientific | 2020 |
| Belnor Farms Limited | Agriculture & fishing | 1948 |
| BEN Childs Building Services Limited | Construction | 2015 |
| BEN Coomber Coaching Limited | Administrative & support | 2025 |
| BEN Hargraves Ltd | Administrative & support | 2026 |
| Benezet Street Limited | Real estate | 2009 |
| Bensfield Mechanical Limited | Construction | 2014 |
| Bentwaters Heating and Plumbing Ltd | Construction | 2013 |
| Bentwaters Parks Limited | Real estate | 1984 |
| Berry Farm Meats Ltd | Wholesale & retail | 2025 |
| Beta BEE Ltd | Manufacturing | 2020 |
| Bettaprint (Woodbridge) Limited | Manufacturing | 2005 |
| Betzbuilt Ltd | Extraterritorial | 1995 |
| Bfitforever Limited | Health & social care | 2015 |
| Bidwins Ltd | Professional & scientific | 2024 |
| Big Sky HR Ltd | Administrative & support | 2015 |
| Biggs Engineering Partnership Ltd | Professional & scientific | 2015 |
| Biltong Properties Ltd | Real estate | 2021 |
| Bingo Barn Ltd | Professional & scientific | 2022 |
| Bishal Properties Ltd | Real estate | 2016 |
| Bishopp & Co Limited | Professional & scientific | 2016 |
| BISTRO@47A Limited | Hospitality | 2024 |
| Bixby Properties Ltd | Real estate | 2019 |
| BK Legal IT Solutions Limited | Information & communication | 2008 |
| BKR (Investments) Ltd | Real estate | 2015 |
| Black Barn Accountants Limited | Professional & scientific | 2008 |
| Black Cat Property Ventures Limited | Hospitality | 2013 |
| Black Cat Research Ltd | Professional & scientific | 2011 |
| Black Dog Chili Company Limited | Extraterritorial | 2013 |
| Black Opal Studios Limited | Information & communication | 2010 |
| Black Rooster Construction Limited | Construction | 2017 |
| Blackrose Consulting Limited | Professional & scientific | 2009 |
| Blackthorn Specialty Ltd | Financial services | 2025 |
| Blink Internet Limited | Information & communication | 2018 |
| Blomvyle Hall Shoot Ltd | Arts & recreation | 2006 |
| Blossom & Bloom Beauty Room Limited | Other services | 2023 |
| Blue Crocus Textiles Ltd | Manufacturing | 2021 |
| Blue Marble Astro Ltd | Information & communication | 2019 |
| Blue Salt FA Limited | Hospitality | 2019 |
| Blue Star Property Limited | Real estate | 2016 |
| Bluemoon Active Ltd | Wholesale & retail | 2023 |
| Blueprint Brands Limited | Professional & scientific | 2025 |
| Bluestone Improvements and Maintenance Ltd | Construction | 2026 |
| Bluette Yachting Limited | Extraterritorial | 2025 |
| Blyth Rise Stays Ltd | Hospitality | 2019 |
| Boasts Industrial Park Lettings Ltd | Real estate | 2025 |
| Bonanza F33C Ltd | Professional & scientific | 2022 |
| Bonobeds Ltd | Manufacturing | 2014 |
| Booking Solutions Limited | Information & communication | 2021 |
| Boomboomtreats Ltd | Wholesale & retail | 2026 |
| Boot Construction (East Anglia) Ltd | Construction | 2015 |
| Boot Consultancy and Developments Limited | Construction | 2014 |
| Boot Property Developments Ltd | Real estate | 2018 |
| Boots 'N' Blades Limited | Manufacturing | 2015 |
| Borroughs Investments Limited | Real estate | 2014 |
| Botanica Plant Collections Ltd | Agriculture & fishing | 2008 |
| Box Worx Ltd | Manufacturing | 2021 |
| Boxtails Limited | Wholesale & retail | 2020 |
| Boydell & Brewer EOT Trustee Limited | Information & communication | 2015 |
| Boydell & Brewer Group Limited | Information & communication | 2003 |
| Boydell & Brewer Limited | Information & communication | 1969 |
| BPA Engineering Suffolk Ltd | Professional & scientific | 2024 |
| Bprd Limited | Financial services | 2024 |
| Bradley & Co Properties Ltd | Real estate | 2024 |
| Bramblebee & Co Interiors Limited | Wholesale & retail | 2025 |
| Bramblebee Cottage Limited | Hospitality | 2025 |
| Brandamba Limited | Information & communication | 2019 |
| BRC Electrical Ipswich Ltd | Construction | 2018 |
| BRC Plumbing Solutions Ltd | Construction | 2021 |
| Breakwater Business Coaching Ltd | Professional & scientific | 2024 |
| Breckland Bridge Limited | Construction | 2014 |
| Breckland Homes (Attleborough) Limited | Construction | 2018 |
| Breckland Homes (Colkirk) Limited | Construction | 2021 |
| Breckland Homes (Mileham) Limited | Construction | 2015 |
| Bredfield Property Limited | Real estate | 2013 |
| Bredfield Village Shop Community Interest Company | Wholesale & retail | 2006 |
| Breezeleaf Limited | Real estate | 1986 |