| Beau Heat Limited | Construction | 2023 |
| Beautiful YOU Nails & Beauty Ltd | Other services | 2019 |
| Becher Designs Limited | Arts & recreation | 2004 |
| Becker Rentals Limited | Administrative & support | 1987 |
| Beckett Design & Build (Beds) Ltd | Construction | 2020 |
| Beckett Developments Ltd | Real estate | 2024 |
| BED ROK Construction Limited | Administrative & support | 2026 |
| Bedford Moves Ltd | Information & communication | 2015 |
| Bedfordshire Pro Bathrooms & Tiling Ltd | Construction | 2019 |
| Beds & Bucks Chauffeur Service Ltd | Transport & logistics | 2022 |
| Bedwell Pizza Kebab Ltd | Hospitality | 2025 |
| BEE Field Projects Limited | Agriculture & fishing | 2022 |
| Beechband Ltd | Manufacturing | 2024 |
| Beechwood Homes Contracting Limited | Construction | 2014 |
| Beechwood Homes Estates Ltd | Real estate | 2019 |
| Beechwood Homes Limited | Construction | 1968 |
| Beehive (Hemel Hempstead) Management Company Limited | Real estate | 2012 |
| Beginning, Middle and END Ltd | Information & communication | 2022 |
| Behaviour Bear Ltd | Education | 2024 |
| Behaviour Path Ltd | Education | 2020 |
| Behind the Scenes Recruitment Limited | Administrative & support | 2018 |
| Beige Healthcare Services Limited | Health & social care | 2016 |
| Beirne Consultancy Ltd | Professional & scientific | 2022 |
| Belanobel Ltd | Other services | 2025 |
| Belfry Construction Limited | Construction | 2008 |
| Belinda Norcliffe Casting Limited | Arts & recreation | 2005 |
| Bell & Claw Limited | Hospitality | 2022 |
| Bell Bar Limited | Real estate | 1987 |
| Bell Bar Management Limited | Real estate | 1987 |
| Bell Commercial Properties Limited | Real estate | 2023 |
| Bell Property Rentals Limited | Real estate | 2020 |
| Bella Beauty & Extensions Hertfordshire Ltd | Other services | 2013 |
| Bella Vita Dante Limited | Other services | 2016 |
| Bellanuel Limited | Mining & quarrying | 2022 |
| Belle VUE Dental Practice Ltd | Health & social care | 2007 |
| Belmont & Knott Ltd | Administrative & support | 2016 |
| Belvara Ltd | Manufacturing | 2024 |
| Bemsit UK Limited | Construction | 2019 |
| BEN Twiston-Davies Limited | Administrative & support | 2023 |
| Ben's Accountancy & Tax Ltd | Professional & scientific | 2025 |
| BEN3MOTORS Ltd | Wholesale & retail | 2023 |
| Bendon Advisory Limited | Other services | 2019 |
| Benefiteer Limited | Professional & scientific | 2010 |
| Benesther Estates Limited | Real estate | 2025 |
| Benesther Ltd | Health & social care | 2015 |
| Benington Park Property Developments Ltd | Real estate | 2005 |
| Benington Services Ltd | Construction | 2018 |
| Benjamin & Windsor Ltd | Wholesale & retail | 2022 |
| Bennie Bassett Ltd | Professional & scientific | 2025 |
| Benruth Limited | Information & communication | 2012 |
| Benster Productions Limited | Information & communication | 2002 |
| Bentley Close Holdings Limited | Real estate | 2017 |
| Bentley Close Management Limited | Households | 1989 |
| Bercaru Limited | Transport & logistics | 2018 |
| Berkeley Court (Bristol) Management Company Limited | Households | 2004 |
| Berkleys Homes Ltd | Real estate | 2018 |
| Berkshire Vehicle Solutions Limited | Wholesale & retail | 2016 |
| BES Electric Company Ltd | Construction | 2021 |
| Best Builders Ever Limited | Construction | 2025 |
| Best Churros Limited | Hospitality | 2023 |
| Best Electrical and Renewables Limited | Construction | 2024 |
| Best Flow Plumbing and Heating Ltd | Construction | 2021 |
| Best Foot Forward Productions Ltd | Arts & recreation | 2022 |
| Best Secure Limited | Financial services | 2009 |
| Best Start Human Resources Limited | Administrative & support | 2007 |
| Bethel Home Residential Limited | Health & social care | 2023 |
| Bethel Trading Ltd | Health & social care | 2025 |
| Bethesda Care Solutions Limited | Administrative & support | 2025 |
| Better Care and Support Services Ltd | Health & social care | 2020 |
| Better Data Ltd | Information & communication | 2017 |
| Better Hair Transplant Ltd | Information & communication | 2022 |
| Better Removals & Storage Limited | Other services | 2018 |
| Better Removals Ltd | Other services | 2018 |
| Better Together Beverages Ltd | Manufacturing | 2025 |
| Beulah Properties Ltd | Real estate | 2012 |
| Beyond Beach Huts Ltd | Real estate | 2011 |
| Beyond Martial Arts Ltd | Arts & recreation | 2015 |
| Beyond Thought Coaching Ltd | Other services | 2024 |
| BFP Services Limited | Professional & scientific | 2020 |
| BFT Hire Limited | Other services | 2017 |
| BFT Mastclimbing Limited | Administrative & support | 1987 |
| Bgen Limited | Financial services | 2017 |
| BGO Mobile Solutions Limited | Information & communication | 2016 |
| BGR Business Consultancy Services Ltd | Hospitality | 2024 |
| Bgsf Ltd | Hospitality | 2022 |
| Bhagyapvt Ltd | Health & social care | 2022 |
| Bhatia Medical Services Limited | Health & social care | 2021 |
| BHB Developments Ltd | Construction | 2019 |
| BHB Resources Holdings Limited | Financial services | 2021 |
| BI Data Intelligence Limited | Administrative & support | 2019 |
| Bi-Oli Limited | Extraterritorial | 2010 |
| BIB Group Holdings Limited | Financial services | 2007 |
| Biek LLP | | 2021 |
| Bierbar Productions Ltd | Information & communication | 2026 |
| Big AB Engineering Ltd | Information & communication | 2023 |
| Big Boss Pizza Hemel Ltd | Hospitality | 2025 |
| Big Cheese International Limited | Real estate | 2002 |
| Big City Conferences Limited | Administrative & support | 2015 |
| Big City Consultants Limited | Professional & scientific | 2017 |
| Big Minibus Limited | Transport & logistics | 2010 |