| B Wright & Sons Ltd | Construction | 2013 |
| BA Homes & Investments Limited | Real estate | 2026 |
| Backlight Ltd | Arts & recreation | 2018 |
| BAD News Delivered Ltd | Manufacturing | 2022 |
| Badgers Artisan Foods Limited | Manufacturing | 2017 |
| Bailey's Sports Bar Limited | Hospitality | 2024 |
| Bakht Group Corporation Ltd | Wholesale & retail | 2023 |
| Bamrad Limited | Arts & recreation | 2020 |
| Bandit Investments Limited | Real estate | 2025 |
| Barbers.Cc Limited | Other services | 2018 |
| Bard Electrics Limited | Construction | 2000 |
| Barnettwinter Limited | Education | 2017 |
| Barnicoat Ltd | Public administration | 2011 |
| Barrett's of ST. Neots Limited | Real estate | 1938 |
| Barrington Asset Management Limited | Financial services | 2024 |
| Barrington Transport Limited | Transport & logistics | 2013 |
| BAS MAX Engineering Limited | Professional & scientific | 2022 |
| Bass Trading Ltd | Financial services | 2024 |
| Bavington-Lloyd Traders Ltd | Wholesale & retail | 2024 |
| Bazzy Trading Ltd | Wholesale & retail | 2025 |
| BB Heating Services Ltd | Construction | 2026 |
| BBM (Berry Business Moggerhanger) Ltd | Extraterritorial | 2013 |
| BBR 2009 Ltd. | Real estate | 2014 |
| BE Acousticx Limited | Professional & scientific | 2020 |
| BE Yellow Ltd | Professional & scientific | 2017 |
| Beam of Light CIC | Health & social care | 2021 |
| Beaufort Gardens (ST. Neots) Management Company Limited | Households | 2008 |
| Beauty by Khushi Ltd | Other services | 2023 |
| Beccl Property Development Ltd | Construction | 2018 |
| Belgic Square Management Company Limited | Real estate | 2004 |
| Bell Great Paxton Ltd | Hospitality | 2024 |
| Bell Tower Homes Ltd. | Construction | 2000 |
| Belongian Ltd | Real estate | 2019 |
| Benchmark Civil Engineering Ltd | Construction | 2018 |
| Benco UK Ltd | Real estate | 2025 |
| Benji&Daisy Ltd | Wholesale & retail | 2025 |
| Bennett Lorusso Property Agents Limited | Real estate | 2006 |
| Berrisford Lettings Ltd | Real estate | 2020 |
| Bertie's Cheesecake Ltd | Manufacturing | 2024 |
| Bespoke Beginnings Ltd | Other services | 2025 |
| Best Furnishing Limited | Wholesale & retail | 2014 |
| Best Market Cafe Limited | Hospitality | 2015 |
| Betabox Computers Limited | Wholesale & retail | 2014 |
| Bethel Residential Properties Limited | Real estate | 2020 |
| Better Brickwork Ltd | Construction | 2017 |
| Betty Bumbles Vintage Tea Room Limited | Hospitality | 2018 |
| Bevgas Limited | Hospitality | 2007 |
| Bewick Holdings Ltd | Construction | 2004 |
| Bewick Homes Limited | Construction | 1994 |
| Bgan Limited | Professional & scientific | 2023 |
| BH Communications Limited | Information & communication | 2015 |
| BI Management Consultants Limited | Information & communication | 2008 |
| Biffab Maintenance Services Ltd | Manufacturing | 2019 |
| Big Sound PR Limited | Professional & scientific | 2014 |
| Big Switch Marketing Ltd | Professional & scientific | 2024 |
| Biggleswade & Hitchin AA Limited | Agriculture & fishing | 2002 |
| Bilal Babam Limited | Other services | 2025 |
| Bildz Ltd | Construction | 2023 |
| Bill Sykes Properties Limited | Real estate | 2000 |
| Binney and Sims Design Ltd | Construction | 2013 |
| Bird Lane Management Limited | Households | 1998 |
| Bite AI Ltd | Information & communication | 2026 |
| BJM Pharma Consulting Limited | Professional & scientific | 2015 |
| BKD Motors Ltd. | Wholesale & retail | 2012 |
| Black Cat Digital Media Limited | Information & communication | 2024 |
| Black Cat Radio C.I.C. | Information & communication | 2011 |
| Black Swan Osteopathic Clinics Ltd | Health & social care | 2011 |
| Black Wolf Limited | Manufacturing | 2012 |
| Black Wolf Locksmiths Limited | Administrative & support | 2021 |
| Black+Cheneviere Ltd | Arts & recreation | 2025 |
| Blackdown Rings Kennels & Cattery Limited | Other services | 2023 |
| Blair Legal Limited | Professional & scientific | 2023 |
| BLK Healthcare Ltd | Health & social care | 2024 |
| Block Security Services Limited | Information & communication | 2020 |
| Bloodstone Capital International Asset Management Limited | Financial services | 2025 |
| Bloodstone Capital International Holdings Limited | Financial services | 2025 |
| Bloodstone Corporate Consulting Limited | Professional & scientific | 2025 |
| Bloomford Limited | Financial services | 2025 |
| Blooming Nails Ltd | Other services | 2023 |
| Blossom by Louise Limited | Other services | 2025 |
| Blue Crest Consulting Limited | Professional & scientific | 2026 |
| Bluebell Mountain Ltd | Professional & scientific | 2018 |
| Blueshift Financial Technology Limited | Information & communication | 2021 |
| Blueshift Property Consulting Ltd | Professional & scientific | 2017 |
| Bluesketch Studio Limited | Professional & scientific | 2015 |
| Boardcraft Limited | Manufacturing | 1997 |
| Bobak Ltd | Other services | 2024 |
| Bock 1 Ltd | Extraterritorial | 2023 |
| Boddington Demolition Limited | Water & waste | 2000 |
| Bodyshop Monkey Ltd | Wholesale & retail | 2022 |
| Bones of ST Neots Ltd | Hospitality | 2025 |
| Bonsai Health Ltd | Wholesale & retail | 2025 |
| Bosfor Turkish ST Neots BBQ Ltd | Hospitality | 2024 |
| Boujee Official Ltd | Wholesale & retail | 2019 |
| Boxhere Ltd | Other services | 2024 |
| Brand H Ltd | Health & social care | 2025 |
| Breathe & Smile Ltd | Professional & scientific | 2024 |
| Brick Frog Ltd | Professional & scientific | 2018 |
| Bricks and Mortar Management Ltd | Real estate | 2022 |
| Bridge Invest ST. Neots Ltd | Administrative & support | 2021 |