| Basecamp Property Ltd | Real estate | 2026 |
| Bashun Logistics Limited | Wholesale & retail | 2025 |
| Basildon Cake Boxes Limited | Wholesale & retail | 2024 |
| Basildon Motoring Centre Limited | Wholesale & retail | 1971 |
| Basildon Moulding Co Limited(The) | | 1962 |
| Basildon Stone Limited | Administrative & support | 2006 |
| Baskervilles Limited | Professional & scientific | 1997 |
| Bassi Estates Ltd | Real estate | 2004 |
| Bassons Limited | Professional & scientific | 2004 |
| BAT Engineering Limited | | 1965 |
| Bathroom Technology Limited | Wholesale & retail | 2003 |
| Batians E-Tech Limited | Professional & scientific | 2007 |
| Battle Heating Ltd | Construction | 2005 |
| Battlewheel Limited | Real estate | 1993 |
| Bawtrees LLP | | 2007 |
| Baxtermead (Northern) Limited | Extraterritorial | 2004 |
| Bayless Consultancy Solutions Limited | Information & communication | 2007 |
| Bayley International Limited | Administrative & support | 2000 |
| Baylis Food & Wine Ltd | Wholesale & retail | 2015 |
| Baytrade Nexus Ltd | Wholesale & retail | 2025 |
| Baytree Transport Limited | Transport & logistics | 2005 |
| Bayview Management (Essex) Limited | Households | 2020 |
| Bayze Trading Ltd | Wholesale & retail | 2020 |
| BB Healthcare Solutions Ltd | Health & social care | 2015 |
| Bcbt Limited | Administrative & support | 2007 |
| Bcdl Consultants Limited | Information & communication | 1999 |
| Bdac Surveying Limited | Professional & scientific | 2004 |
| BDM Agency Ltd | Administrative & support | 2024 |
| BE OUR Property Ltd | Real estate | 2022 |
| BE Unique for Less Limited | Wholesale & retail | 2017 |
| Beadle Housing Limited | Real estate | 2020 |
| Beamdual Limited | | 1986 |
| Bearfield Properties Limited | Real estate | 2000 |
| Beaumont Consultancy Services Limited | Professional & scientific | 2006 |
| Beauty Created Limited | Manufacturing | 2004 |
| Beauty Shine Ltd | Wholesale & retail | 2023 |
| Beauty Spot App Ltd | Other services | 2021 |
| Beauty Street Limited | Other services | 2021 |
| Beckmarnao Limited | Administrative & support | 2025 |
| Beckwith & SON (Engineering) Limited | Manufacturing | 1995 |
| Becontree Heating & Plumbing Merchants Ltd | Wholesale & retail | 2006 |
| Becontree Plant Hire Limited | Administrative & support | 1976 |
| Beecham Research Ltd. | Information & communication | 1991 |
| Beechmead Limited | Transport & logistics | 2007 |
| Beechwood Carpentry Limited | Construction | 2004 |
| Beechwood Estates (UK) Limited | Construction | 1998 |
| Beefim House Limited | Wholesale & retail | 2025 |
| Beetoch Limited | Wholesale & retail | 2018 |
| Beighton Developments Ltd | Construction | 2022 |
| Beingfit Ltd | Wholesale & retail | 2025 |
| BEL Grow Copy Ltd | Professional & scientific | 2025 |
| Belari Limited | Professional & scientific | 2008 |
| Belladonna Projects Limited | Information & communication | 2021 |
| Bellax Limited | Real estate | 2025 |
| Belle Casa (Chelmsford) Limited | Administrative & support | 2003 |
| Belle Mode Reve Limited | Manufacturing | 2012 |
| Belle VUE Property Services Limited | Real estate | 1990 |
| Bellhouse Plumbing and Heating Ltd | Construction | 2005 |
| Bellinkine Limited | Health & social care | 2022 |
| Bellsik Properties Limited | Real estate | 2022 |
| Belmont & Usher Ltd | Construction | 2016 |
| Belmont Day Nursery Ltd | Education | 2005 |
| Belmont Solutions Ltd. | Professional & scientific | 2000 |
| Belonia UK Ltd | Wholesale & retail | 2026 |
| Belvedere Warehousing and Distribution Limited | Extraterritorial | 2006 |
| Belwood Homes Limited | Construction | 2002 |
| Bembridge Air Hire Limited | | 1956 |
| Bemysky Ltd | Wholesale & retail | 2021 |
| BEN & EDI Gardening & Landscaping Ltd | Administrative & support | 2019 |
| Benchstore Limited | Extraterritorial | 2007 |
| Bendral Limited | | 1985 |
| Benfleet Physiotherapy Limited | Health & social care | 2007 |
| Bengal Republic Ltd | Hospitality | 2019 |
| Benicraft Estates Ltd | Real estate | 2021 |
| Benicraft Investments Limited | Administrative & support | 2013 |
| Benicraft Limited | Wholesale & retail | 1994 |
| Benicraft Trading Limited | Administrative & support | 2014 |
| Benigna Ministries Collective Limited | Education | 2025 |
| Benjamin Oswald Limited | Water & waste | 2014 |
| Bennet Place Limited | Health & social care | 2024 |
| Benroy & Company Limited | Administrative & support | 2016 |
| Benson-Sedgwick Engineering Limited | Manufacturing | 1924 |
| Bensons Printing Company Limited | Manufacturing | 2003 |
| Bensusan Butt Limited | Extraterritorial | 1999 |
| Bere Osyth Limited | Wholesale & retail | 1972 |
| Berkeley Brokerage Limited | Other services | 1996 |
| Beryl Genius Creations Ltd | Wholesale & retail | 2025 |
| Besh Food Co. Limited | Hospitality | 1997 |
| Bespoke Boutique Essex Ltd | Other services | 2020 |
| Bespoke Design Studio Limited | Wholesale & retail | 2008 |
| Bespoke Interior Design Services Limited | Wholesale & retail | 2000 |
| Bespoke Logistics Limited | Transport & logistics | 2001 |
| Bespoke Solutions Ltd | Professional & scientific | 2014 |
| Best Choice Letting Agents Limited | Construction | 2007 |
| Best for YOU PVT Ltd | Wholesale & retail | 2026 |
| Best Hand Carwash EN Ltd | Administrative & support | 2022 |
| Best Inn Limited | Hospitality | 2010 |
| Bestfood of Rayne Ltd | Hospitality | 2018 |
| Bestpark Consultants Limited | Professional & scientific | 2003 |
| Bethell & Clark Limited | Health & social care | 1981 |