| BC Asset Holdings Ltd | Financial services | 2026 |
| BC Premises Ltd | Real estate | 2025 |
| BC Property Operations Ltd | Real estate | 2026 |
| BC Steelfixing Limited | Construction | 2024 |
| Bcds Homes Limited | Real estate | 2022 |
| Bcel Ltd | Professional & scientific | 2017 |
| Bcis Groundworks Ltd | Construction | 2023 |
| BD Buddy Limited | Information & communication | 2024 |
| BE : 1 Media Limited | Professional & scientific | 2024 |
| BE in Property Limited | Real estate | 2019 |
| BE More Nomad Ltd | Hospitality | 2025 |
| BE Mortgages Ltd | Financial services | 2021 |
| BEA Sweet Limited | Arts & recreation | 2018 |
| Beach House Restaurant Limited | Hospitality | 2025 |
| Beach House Therapy Ltd | Health & social care | 2026 |
| Bean Games Limited | Information & communication | 2024 |
| Bear Creative Agency LLP | | 2020 |
| Bear LOS Ltd | Real estate | 2019 |
| Bear on Film Ltd | Information & communication | 2023 |
| Bearded Builders UK Limited | Construction | 2018 |
| Bearwolf Studios Ltd | Information & communication | 2018 |
| Beasley Media Ltd | Information & communication | 2019 |
| Beau Healthcare Limited | Health & social care | 2013 |
| Beau Interiors Limited | Wholesale & retail | 2004 |
| Beauchamp Built Ltd | Manufacturing | 2022 |
| Beaumont Fencing Ltd | Construction | 2022 |
| Beaumontas Limited | Information & communication | 2009 |
| Beautiful Healthy Home Limited | Wholesale & retail | 2021 |
| Beaver on JOB Limited | Transport & logistics | 2014 |
| Bebb Family Holdings Limited | Real estate | 2024 |
| Becky Bates Creative and Photography Limited | Professional & scientific | 2025 |
| Bedrock Graphics Limited | Manufacturing | 1994 |
| Bedrok Developments Limited | Real estate | 2002 |
| BEE House Proud Ltd | Administrative & support | 2025 |
| Begumbook Limited | Information & communication | 2024 |
| Beke Hall Estates Limited | Construction | 2024 |
| Belfair Builders and Interiors LLP | | 2024 |
| Belfair's Office Limited | Wholesale & retail | 2019 |
| Belfairs Essentials Ltd | Wholesale & retail | 2026 |
| Belfairs Point Management Company Limited | Real estate | 2005 |
| Bella Parties Limited | Arts & recreation | 2008 |
| Bellfinn Consultants Limited | Professional & scientific | 2023 |
| Belliss Investments Limited | Financial services | 2018 |
| Bellygoodness Limited | Manufacturing | 2022 |
| Belong - Fifty Ltd | Professional & scientific | 2025 |
| BEN Gregory Hair Limited | Other services | 2025 |
| BEN Maddison Ltd | Education | 2020 |
| BEN Thomas Ltd | Construction | 2022 |
| Benets Management Ltd | Households | 2025 |
| Benets Property Management Ltd | Households | 2025 |
| Benfleet Brickwork & Construction Ltd | Other services | 2007 |
| Benfleet Nova Limited | Real estate | 2026 |
| Benjamin Clark Engineering Limited | Manufacturing | 2019 |
| Benjamin Mills Limited | Arts & recreation | 2017 |
| Benjys Leigh Limited | Manufacturing | 2022 |
| Bennygreens Limited | Information & communication | 2018 |
| Benpod Holdings Ltd | Real estate | 2026 |
| Benson & Ashley Limited | Wholesale & retail | 1993 |
| Beresford Property Management Ltd | Extraterritorial | 2021 |
| Berkeley Court Management Company (Rochford) Limited | Households | 1987 |
| Berkerley & Co Ltd | Professional & scientific | 2018 |
| Berkley Court (Westcliff) Limited | Households | 1999 |
| Bernard Gooding Associates LLP | | 2010 |
| Berrytree Publishing Ltd | Information & communication | 2017 |
| Bertroy Homes Ltd | Construction | 2016 |
| Bertroy SM Ltd | Real estate | 2026 |
| Bespoke Recruitment (Construction) Limited | Administrative & support | 2001 |
| Bespoke Watch Servicing Ltd | Other services | 2024 |
| Best 4 Advice Ltd | Financial services | 2005 |
| Best of UK (Advisory) Ltd | Professional & scientific | 2025 |
| Best Water Group Limited | Professional & scientific | 2026 |
| Best Water Monitoring Limited | Professional & scientific | 2021 |
| Bet-Chip Limited | Information & communication | 2025 |
| Better Bake London Limited | Wholesale & retail | 2016 |
| Better Learning UK Limited | Education | 2010 |
| Beyond the Setback CIC | Administrative & support | 2025 |
| Beyond Your Limits Ltd | Arts & recreation | 2019 |
| BG Construction Group Ltd | Construction | 2023 |
| BGC & NAC Holdings Ltd | Real estate | 2025 |
| BH Property Solutions Ltd | Real estate | 2020 |
| BH Railway Infrastructure Consultants Limited | Professional & scientific | 2017 |
| Bhadj Trading Limited | Professional & scientific | 2015 |
| Bhalu Limited | Real estate | 2023 |
| Bhhy Properties Ltd | Real estate | 2025 |
| BHJ Trading Properties Limited | Real estate | 2025 |
| Big Red Back ROW Ltd | Other services | 2014 |
| Big Riff Films Limited | Information & communication | 2024 |
| Bike Vault Limited | Manufacturing | 2009 |
| Bikes & Bits Ltd | Extraterritorial | 2024 |
| Billion Brokers Ltd | Financial services | 2023 |
| Billy Adams Boxing Limited | Arts & recreation | 2025 |
| Billy Murphy Art Ltd | Arts & recreation | 2026 |
| Billys Builders Ltd | Construction | 2024 |
| Binuzehwa Ltd | Real estate | 2025 |
| Biochem Pest Control Limited | Administrative & support | 2016 |
| Bite N EAT Ltd | Hospitality | 2022 |
| BK & Co Projects Ltd | Construction | 2019 |
| Bkbg Rentals Limited | Real estate | 2021 |
| Black and Sigi Limited | Manufacturing | 2018 |
| Black Cat Fundraising Ltd | Administrative & support | 2024 |