| Bay Apartments (Lyme Regis) Limited | Households | 2013 |
| Bay Harbour View Limited | Real estate | 1979 |
| Bay Kitchens Ltd | Construction | 2014 |
| Bay Solutions Ltd | Professional & scientific | 2026 |
| BAY4 LLP | | 2010 |
| Bayer Professional Services Ltd | Wholesale & retail | 2025 |
| Baynham-Knight Writing Ltd | Professional & scientific | 2020 |
| Baypoint Surveys Limited | Construction | 2005 |
| Baysal & Co Grooming Ltd | Other services | 2026 |
| Bayside Business Centre Ltd | Real estate | 2013 |
| Bazanela Ltd | Manufacturing | 2022 |
| BB Aviation Services Ltd | Administrative & support | 2018 |
| BB8 Limited | Real estate | 2017 |
| Bbbtl Ltd | Real estate | 2023 |
| BBD Boom Ltd | Other services | 2017 |
| BBJ Limited | Financial services | 2018 |
| Bbusybee Ltd | Wholesale & retail | 2024 |
| BBX Limited | Wholesale & retail | 2013 |
| BBX Media Ltd | Administrative & support | 2020 |
| BC Investco 1 Limited | Other services | 2015 |
| BCF (Blackhill) Ltd | Construction | 2015 |
| BCL U.K. Limited | Transport & logistics | 2020 |
| Bcmsocial Ltd | Hospitality | 2019 |
| Bcos Software Ltd | Information & communication | 2017 |
| BCP Damp Proofing Ltd | Extraterritorial | 2024 |
| BCP Heating Solutions Limited | Construction | 2023 |
| BCP Media Group Limited | Manufacturing | 2018 |
| BCP Taxi Ltd | Transport & logistics | 2022 |
| BCP Trade Center Ltd | Wholesale & retail | 2023 |
| BCS Dorset Ltd | Households | 2019 |
| BCS Logistics Ltd | Mining & quarrying | 2021 |
| BCW Construction & Projects Limited | Construction | 2026 |
| BDL Mouthguards Limited | Professional & scientific | 1999 |
| BDS Global Group Ltd | Financial services | 2025 |
| BE Fearless Limited | Wholesale & retail | 2022 |
| BE Smart Holdings Limited | Wholesale & retail | 2019 |
| BEA Adventurous Ltd | Information & communication | 2022 |
| Beach Bar Diner Ltd | Hospitality | 2017 |
| Beach Coffee Ltd | Hospitality | 2019 |
| Beach Vibe Properties Ltd | Real estate | 2024 |
| Beachbum Inc Limited | Extraterritorial | 2015 |
| BEACHBUM4LIFE Limited | Real estate | 2025 |
| Beachwise CIC | Education | 2025 |
| Beacon Data Consulting Limited | Information & communication | 2026 |
| Beacon Property Group Ltd | Construction | 2025 |
| Beaglehole Electrics Ltd | Construction | 2025 |
| Beakon Mart Ltd | Wholesale & retail | 2025 |
| Beales Properties Ltd | Real estate | 2016 |
| Beaming Futures Kagayaku Miraie Limited | Information & communication | 2025 |
| Bear Architects Limited | Professional & scientific | 2021 |
| Bear Media Studios Ltd | Administrative & support | 2019 |
| Beard Surgeon Ltd | Wholesale & retail | 2021 |
| Beardy BOO Games Limited | Information & communication | 2025 |
| Bearings House Management Company Limited | Households | 2020 |
| Bearman Hair Limited | Other services | 2017 |
| Beast-Competitions Ltd | Arts & recreation | 2025 |
| Beatmatika Ltd | Information & communication | 2020 |
| Beatrice Aidoo Ltd | Wholesale & retail | 2026 |
| Beatriz Patarata Limited | Professional & scientific | 2025 |
| Beatus Properties Limited | Real estate | 2025 |
| Beaufield Developments Ltd | Real estate | 2008 |
| Beaumont Consulting Group Ltd | Professional & scientific | 2025 |
| Beauregard Homes Limited | Real estate | 2021 |
| Beauterior Ltd | Wholesale & retail | 2025 |
| Beautiful INK Limited | Wholesale & retail | 2012 |
| Beauty Buildings Ltd | Real estate | 2021 |
| Beauty Estates Ltd | Real estate | 2023 |
| Beauty Sculpting Room Ltd | Other services | 2021 |
| Beauty Tulips Limited | Wholesale & retail | 2014 |
| Beautyaffairs Afrikana Ltd | Other services | 2024 |
| Bebc Holdings Ltd | Financial services | 2026 |
| Beckett Electrics Limited | Construction | 2009 |
| Becky's Chic Limited | Other services | 2025 |
| Becom Brazil Limited | Wholesale & retail | 2025 |
| Becuz UK Limited | Wholesale & retail | 2025 |
| BEE Better Consulting Limited | Professional & scientific | 2025 |
| BEE Lines Investment Ltd | Real estate | 2020 |
| BEE Mission 500 Community Interest Company | Manufacturing | 2021 |
| BEE Mission Ltd | Agriculture & fishing | 2019 |
| Beebombs Ltd | Wholesale & retail | 2018 |
| Beebranch Limited | Agriculture & fishing | 2025 |
| Beechcroft COM1 Ltd | Real estate | 2021 |
| Beechcroft R1 Ltd | Real estate | 2021 |
| Beechey 11 Ltd | Real estate | 2020 |
| Beechey 11 Management Ltd | Households | 2022 |
| Beechey 11 Sales Ltd | Real estate | 2022 |
| Beelegent Cosmetics Ltd | Wholesale & retail | 2025 |
| Beem Search Limited | Administrative & support | 2019 |
| Beer&Autentica Ltd | Health & social care | 2022 |
| Beerbassador Ltd | Hospitality | 2025 |
| Beetle Group Ltd | Manufacturing | 2025 |
| Begbroke Lane Property Limited | Real estate | 2026 |
| Behaviour Leadership Ltd | Education | 2024 |
| Behold Ltd | Information & communication | 2017 |
| Beig Holdings Ltd | Real estate | 2018 |
| Beig Investments Ltd | Real estate | 2020 |
| Bejouh Limited | Wholesale & retail | 2022 |
| Belachew Engineering Ltd | Professional & scientific | 2025 |
| Belakva Limited | Real estate | 2020 |
| Belfield Homes (Ampfield) Limited | Construction | 2021 |