| Belo Analytics Ltd | Administrative & support | 2015 |
| Belvedere Opticare Limited | Wholesale & retail | 2025 |
| BEN JOB Ltd | Construction | 2014 |
| Ben-Efit Performance Ltd | Wholesale & retail | 2021 |
| Benicore Ltd | Information & communication | 2017 |
| Beninthemix Ltd | Professional & scientific | 2025 |
| Bennu's Healthcare PVT. Ltd | Health & social care | 2019 |
| Bernoulli Aviation Ltd | Professional & scientific | 2026 |
| Berrylands (Orpington) Residents Company Limited | Households | 1985 |
| Berwick Hill (Brenchley) Limited | Real estate | 2019 |
| Berwick Hill (Lewes) Limited | Real estate | 2018 |
| Berwick Hill Properties (Billingshurst) Limited | Real estate | 2026 |
| Berwick Hill Properties (Guildford) Limited | Real estate | 2020 |
| Berwick Hill Properties Limited | Professional & scientific | 2002 |
| Bespoke Botanicals Preservation Ltd | Manufacturing | 2022 |
| Bespoke Fire Protection Ltd | Construction | 2010 |
| Best Bunk Beds Ltd | Manufacturing | 2011 |
| Best Kitchen Fitting Limited | Construction | 2017 |
| Best Pizza in Town Ltd | Hospitality | 2017 |
| Best Quality Fitting Limited | Construction | 2009 |
| Best Quality Fitting London Ltd | Construction | 2026 |
| Best YOU Educational Services Ltd | Education | 2025 |
| Best Yummy Limited | Hospitality | 2024 |
| Bestcare Launderette Limited | Other services | 2011 |
| Bethany Joelle Consulting Ltd | Professional & scientific | 2026 |
| Bethel Lodge Ltd | Real estate | 2020 |
| Better Aspect Signalling Installation Ltd | Construction | 2015 |
| Better Windows Corporation Ltd | Construction | 1997 |
| Better Windows Installation Services Ltd | Construction | 2008 |
| Beval Btls Limited | Real estate | 2018 |
| Bevan Franklin Ltd | Health & social care | 2020 |
| Bexley & Bromley Roofing Limited | Construction | 2015 |
| Bexleyheath Skips Limited | Extraterritorial | 2008 |
| Beyaz Holding Ltd | Financial services | 2025 |
| Beyond Enterprises Ltd | Wholesale & retail | 2022 |
| Beyond Four Walls Limited | Professional & scientific | 2019 |
| Beyond Heating Ltd | Construction | 2011 |
| BEZ Idakula Music Ltd | Information & communication | 2023 |
| BF Plumbing and Heating Ltd | Construction | 2022 |
| BGO 1 Limited | Wholesale & retail | 2011 |
| BH Property Ventures Ltd | Real estate | 2026 |
| Bhadra Ventures Ltd | Financial services | 2022 |
| BHC Property Maintenance Limited | Manufacturing | 2020 |
| BHZ Investment Limited | Real estate | 2003 |
| BI Visual Analytics Limited | Information & communication | 2025 |
| Big Arch Ltd | Arts & recreation | 2023 |
| Big Clean Company Limited | Administrative & support | 2025 |
| Big Little Ideas Ltd | Professional & scientific | 2011 |
| Big Red Feet Ltd. | Wholesale & retail | 2011 |
| Bigjalebi Ltd | Wholesale & retail | 2020 |
| Bilacraft Limited | Real estate | 2009 |
| Bilen Kebab Ltd | Hospitality | 2026 |
| Bilingual Little People Ltd | Administrative & support | 2017 |
| Billthebuilder Ltd | Manufacturing | 2026 |
| BIO Live Aestetics Limited | Other services | 2026 |
| Biomedical Business Partners Limited | Professional & scientific | 2002 |
| Birch Court Properties Ltd | Households | 2013 |
| Birch Residents Company Limited | Households | 1972 |
| Birds Away Falconry Services Ltd | Professional & scientific | 2024 |
| Birkdale Ventures Limited | Real estate | 2024 |
| Birkinshaw Associates Ltd | Professional & scientific | 2015 |
| Birt & Tang Ltd | Manufacturing | 2002 |
| Bishop Climate Ministry Ltd | Wholesale & retail | 2024 |
| Bishop Property Estates Ltd | Real estate | 2023 |
| BIT Cloud Ltd | Construction | 2018 |
| Biznest Hub Ltd | Administrative & support | 2025 |
| Bizzkickz Ltd | Wholesale & retail | 2025 |
| BJ Vault Ltd | Wholesale & retail | 2025 |
| BK & AK Properties Limited | Real estate | 2020 |
| Black Grape Ltd | Information & communication | 2014 |
| Black Hole Bins Ltd. | Water & waste | 2026 |
| Black Sea Cereal Co Limited | Wholesale & retail | 2024 |
| Blackbroke Limited | Real estate | 1980 |
| Blackbrook Consulting Limited | Administrative & support | 2014 |
| Blackgold Consulting Ltd | Administrative & support | 2019 |
| Blackspace Ltd | Professional & scientific | 2026 |
| Blackthorn Grove (Orpington) Management Limited | Households | 2016 |
| Blakebuild Ltd | Construction | 2020 |
| Blakemores 1982 Limited | Hospitality | 2017 |
| Blakes Bakes Ltd | Manufacturing | 2025 |
| Blazing Chicken Ltd | Hospitality | 2026 |
| Blessing K Operative Ltd | Administrative & support | 2018 |
| Bleu Plant and Access Limited | Construction | 2024 |
| Bleuy Acquisitions Ltd | Real estate | 2021 |
| Bling Boutique Ltd | Wholesale & retail | 2025 |
| Bliss Nails and Beauty Limited | Other services | 2026 |
| Blisslove Media Limited | Information & communication | 2013 |
| BLM Films Limited | Information & communication | 2014 |
| Bloom Care Kids Ltd | Health & social care | 2026 |
| Bloom Nail Lounge Ltd | Other services | 2026 |
| Bloomhandmade Ltd | Wholesale & retail | 2022 |
| Blossom Years Limited | Education | 2009 |
| Blow LDN Ltd | Other services | 2021 |
| Blu-Lite Electrical Services Limited | Construction | 1991 |
| Blue Beat Media Consultancy Limited | Professional & scientific | 2023 |
| Blue Box Estates Limited | Administrative & support | 2022 |
| Blue Box Self Storage (Coleshill) Limited | Agriculture & fishing | 2015 |
| Blue Box Self Storage (Midlands) Limited | Administrative & support | 2011 |
| Blue Box Self Storage (North) Limited | Administrative & support | 2013 |
| Blue Eyes Solutions Ltd | Wholesale & retail | 2014 |