| Bright Support Services Limited | Administrative & support | 2019 |
| Brighthaven Stays Ltd | Real estate | 2025 |
| Brightlite Electrical Services Limited | Construction | 2001 |
| Brileo Ltd | Construction | 2018 |
| Brilliant Focus Limited | Professional & scientific | 2024 |
| Brinkley Roofing Limited | Construction | 2014 |
| Brisons Carpentry Limited | Construction | 2012 |
| Britam International Limited | Transport & logistics | 1997 |
| Britcore Solutions Limited | Administrative & support | 2023 |
| Brits Treats Ltd | Wholesale & retail | 2013 |
| BRK Engineering Company Limited | Real estate | 1986 |
| BRM Haulage Limited | Transport & logistics | 2018 |
| Bronze & White Limited | Real estate | 2024 |
| Bronzed and Beautiful Beauty Salon Limited | Other services | 2015 |
| Brook Farm Livery Limited | Arts & recreation | 2008 |
| Brookman Capital Limited | Real estate | 2015 |
| Brookman Property Limited | Real estate | 2023 |
| Broomhill Care Group Ltd | Administrative & support | 2018 |
| Browicks Construction Ltd | Construction | 2023 |
| Brownes Logistics Ltd | Transport & logistics | 2025 |
| Broxbourne Station Cars Ltd | Transport & logistics | 2003 |
| Bruce Welton Ltd | Construction | 1999 |
| Brufc Supporters Group Limited | Arts & recreation | 2015 |
| BSK Financial Ltd | Financial services | 2026 |
| BSS Refresh Ltd | Information & communication | 2012 |
| BTL Bardfield Limited | Wholesale & retail | 2020 |
| Buckingham Coatings Limited | Construction | 2016 |
| Building Register Limited | Information & communication | 2025 |
| Building Safety Consulting Limited | Professional & scientific | 2024 |
| Bull & Co Accountancy Services Ltd | Professional & scientific | 2026 |
| Bulletware Games Ltd | Information & communication | 2025 |
| Bullnose Bull Terriers Limited | Agriculture & fishing | 2015 |
| Burbridge 2000 Limited | Manufacturing | 1990 |
| Burgoyne Steel Consultancy Ltd | Manufacturing | 2024 |
| Burnt Orange Construction Ltd | Construction | 2017 |
| Burrito Boys Ltd | Administrative & support | 2016 |
| Burroak Limited | Construction | 2008 |
| Burton's Mill Stalham Management Ltd | Real estate | 2008 |
| Burtons Mill Stalham Freehold Limited | Real estate | 2025 |
| BUS4US Ltd | Transport & logistics | 2010 |
| Bushett Rise Ltd | Households | 2021 |
| Business Activities Limited | Hospitality | 2019 |
| Butterfly Transfers Limited | Extraterritorial | 2013 |
| BUYACAR4LESS Ltd | Wholesale & retail | 2026 |
| Buzz CRM Ltd | Information & communication | 2023 |
| Buzz Flight Here Travel Limited | Transport & logistics | 2026 |
| Bwownies Ltd | Manufacturing | 2021 |
| BY Brew Ltd | Professional & scientific | 2022 |
| BY Sophie Treats Ltd | Manufacturing | 2024 |
| Bytide Capital Ltd | Real estate | 2026 |
| C & D Services (UK) Limited | Wholesale & retail | 2007 |
| C & V Consultancy Services Ltd | Information & communication | 2018 |
| C & V Solutions Limited | Health & social care | 2015 |
| C Gallagher Property Ltd | Real estate | 2021 |
| C J Foods Trading Limited | Wholesale & retail | 2014 |
| C J Wiffen Construction Limited | Construction | 2021 |
| C J Yates Construction Limited | Construction | 2010 |
| C J Yates Ltd | Construction | 2021 |
| C P Diesel Limited | Wholesale & retail | 2023 |
| C Saward Electrical Contractors Limited | Construction | 2006 |
| C&C Podiatry Limited | Other services | 2022 |
| C&D Carpentry and Construction Ltd | Construction | 2018 |
| C&F Medical Ltd | Health & social care | 2025 |
| C&G Maintenance Services Limited | Construction | 2005 |
| C&S Hair Limited | Other services | 2012 |
| C.& V.Swift,Limited | | 1936 |
| C.Gallagher Developments Ltd | Construction | 2020 |
| Cable Connect Services Ltd | Construction | 2022 |
| Cableship Limited | Real estate | 2013 |
| Cabotlane Ltd | Construction | 2017 |
| Caferen Limited | Hospitality | 2016 |
| Café IB Company Limited | Financial services | 2015 |
| Call CAB Braintree Ltd | Transport & logistics | 2025 |
| Calokiro Limited | Arts & recreation | 2016 |
| Cambium Investments Limited | Financial services | 2021 |
| Cambridge Burger Company Limited | Hospitality | 2022 |
| Cambridge Mind Limited | Administrative & support | 2019 |
| Cambridge Summon Consultancy Ltd | Professional & scientific | 2017 |
| Cameron Specialty Holdco Limited | Financial services | 2025 |
| Cameron Specialty Insurance Limited | Financial services | 2022 |
| Cami Communications Ltd | Professional & scientific | 2013 |
| Campion Equestrian Construction Ltd. | Construction | 2020 |
| Cancersure Ltd | Health & social care | 2023 |
| Cannderwood Investments Ltd | Real estate | 2024 |
| Cano Catering Ltd | Hospitality | 2024 |
| Canopan Limited | Hospitality | 2017 |
| Capital and Counties Electrical Ltd | Construction | 2018 |
| Capital M Marketing Ltd | Administrative & support | 2022 |
| Capital Plant Limited | Manufacturing | 2001 |
| Capital Release Ltd | Wholesale & retail | 2024 |
| Capital Valley Products Limited | Wholesale & retail | 2025 |
| Capris Holdings UK Limited | Information & communication | 2015 |
| Capybara 88 Limited | Hospitality | 2026 |
| Car Charging Limited | Energy | 2020 |
| Car REG Promo Limited | Other services | 2017 |
| Cara Business Services Limited | Wholesale & retail | 2013 |
| Carbon Electrical Limited | Construction | 2013 |
| Care ARK Ltd | Education | 2025 |
| Care Drycleaning and Tailoring Ltd | Other services | 2013 |
| Careco (UK) Limited | Wholesale & retail | 2009 |