| Belvedere Court 2009 Limited | Households | 2009 |
| BEN Charles Event Tech Ltd | Information & communication | 2025 |
| BEN Phillips Automotive Limited | Professional & scientific | 2017 |
| BEN Waters Limited | Arts & recreation | 2010 |
| Bender International Limited | Construction | 1977 |
| Bennett Family Holdings Ltd | Financial services | 2023 |
| Bennett Partnership (Essex) Ltd | Wholesale & retail | 2015 |
| Bennetts Funeral Directors (Property) Limited | Real estate | 2023 |
| Bentley Golf 2004 Ltd | Arts & recreation | 1984 |
| Bentley Golf and Country Club Limited | Arts & recreation | 1970 |
| Bentley Golf Club Limited | Other services | 2003 |
| Bentley Golf Holdings PLC | Real estate | 2004 |
| Bentley Grove Financial Solutions LLP | | 2009 |
| Bentley Mews Limited | Real estate | 2020 |
| Bentros Limited | Professional & scientific | 2003 |
| Berkeley Townsend Limited | Professional & scientific | 2000 |
| Bermondsey Studios Limited | Real estate | 2025 |
| Bernard Property Sales & Lettings Limited | Real estate | 2025 |
| Bernards Management Company Limited | Administrative & support | 2008 |
| Berryhill Property Group Ltd | Real estate | 2018 |
| Berrywood Estates Limited | Other services | 1994 |
| Bespoke Autostyling Ltd | Wholesale & retail | 2010 |
| Bespoke Glass Structures Ltd | Construction | 2018 |
| Bespoke Office Creative Limited | Wholesale & retail | 2013 |
| Bespoke Vehicle Security Ltd. | Extraterritorial | 2018 |
| Bessie BAE Ltd | Wholesale & retail | 2025 |
| Best Choice Contractor Limited | Construction | 2018 |
| Best Electro Ltd | Wholesale & retail | 2019 |
| Best Equine & Agricultural Fencing Ltd. | Administrative & support | 2022 |
| Best Memorials Ltd | Manufacturing | 2019 |
| Best Star Nails Ltd | Other services | 2020 |
| Better With Property Ltd | Real estate | 2022 |
| Beulah Creations Limited | Professional & scientific | 2011 |
| Beyond Bold Ventures Ltd | Information & communication | 2025 |
| Beyond Creative Homes Limited | Construction | 2020 |
| Beyond Money Limited | Financial services | 2008 |
| BFR Property Ltd | Real estate | 2024 |
| BH Landscapes SW Ltd | Administrative & support | 2025 |
| Bhagavan Muruga Investments Limited | Real estate | 2023 |
| BHL Property’S Ltd | Real estate | 2023 |
| Bhuiya Ltd | Hospitality | 2020 |
| Biab by ABS Ltd | Other services | 2025 |
| Bicknacre Limited | Construction | 2025 |
| Bifold Door Repair Ltd | Construction | 2023 |
| Bifold FIX Ltd | Manufacturing | 2025 |
| Big Property Developments Limited | Real estate | 2016 |
| Billet Land Ltd | Extraterritorial | 2006 |
| Billingshurst House RTM Company Limited | Households | 2024 |
| Billington Sheep Farmers Limited | Agriculture & fishing | 2011 |
| Bilton & Johnson (Building) Co Ltd | Construction | 2004 |
| Bilton & Johnson (Construction) Ltd | Construction | 2021 |
| Bilton & Johnson Holdings Limited | Financial services | 2022 |
| Biochromex Ltd | Professional & scientific | 2017 |
| Bionutra Ltd | Professional & scientific | 2011 |
| Birchgrove Estate Essex Limited | Real estate | 2025 |
| Birchills Estates Ltd | Other services | 2017 |
| Birchills Ltd | Real estate | 2015 |
| Birchills Property Ltd | Real estate | 2016 |
| Bird Lane Field Company Limited | Professional & scientific | 2010 |
| Birley Grange Estate Management Limited | Real estate | 2025 |
| Bishop Stortford Truck Sales Ltd | Wholesale & retail | 2025 |
| Bishopscourt Financial Holdings Limited | Financial services | 1984 |
| Bishopscourt Group Services Limited | Administrative & support | 1985 |
| Bites by L Ltd | Manufacturing | 2025 |
| Bits and Bytes (Essex) Limited | Information & communication | 2008 |
| Bizimage Ltd | Wholesale & retail | 2020 |
| Bjfc Building Services Ltd | Construction | 2014 |
| BJJ Sanctuary Ltd | Administrative & support | 2023 |
| BKB Technical Inspection Services Ltd | Professional & scientific | 2016 |
| BKP Investments Limited | Real estate | 2017 |
| Black FOX Projects Ltd | Construction | 2024 |
| Black Oakwood Ltd | Real estate | 2021 |
| Black Sofa L Limited | Transport & logistics | 2017 |
| Black Swan Resourcing Ltd | Administrative & support | 2021 |
| Blackbarn Advisory Ltd | Financial services | 2026 |
| Blackhawk Recovery Ltd | Wholesale & retail | 2022 |
| Blackmore Design Limited | Professional & scientific | 2005 |
| Blackshaw Homes (Sales and Lettings) Ltd | Real estate | 2009 |
| Blackwall Trading Management Limited | Real estate | 1990 |
| Blackwater Mechanical Ltd | Construction | 2019 |
| Blackwood Crest Ltd | Hospitality | 2025 |
| Blade Filming Ltd | Other services | 2011 |
| Blade Group Ltd | Administrative & support | 2020 |
| Blaggers Records Ltd | Information & communication | 2013 |
| Blake Engineering Consultant Ltd | Professional & scientific | 2019 |
| Blakeney Homes and Estates Limited | Real estate | 2001 |
| Blakeney Lifestyle Limited | Wholesale & retail | 2022 |
| Blbc Ltd | Hospitality | 2021 |
| Blcp Eden 1 Limited | Real estate | 2019 |
| Blcp Eden 2 Limited | Real estate | 2019 |
| Blenheim Square (North Weald) Management Limited | Households | 2010 |
| Bliss Recruits Ltd | Administrative & support | 2021 |
| Blitemedia Ltd | Professional & scientific | 2025 |
| BLM Rail Services Ltd | Professional & scientific | 2011 |
| Bloktek Ltd | Information & communication | 2022 |
| Blondes of Brentwood Limited | Other services | 2016 |
| Bloodline Performance Ltd | Health & social care | 2026 |
| Bloom and Prosper Limited | Professional & scientific | 2021 |
| Bloompage Consulting Limited | Health & social care | 2019 |
| Blooms of Essex Wholesale Ltd | Wholesale & retail | 2019 |