| Avondale Records Ltd | Information & communication | 2025 |
| Awan Mobiles Ltd | Wholesale & retail | 2018 |
| Ayris Psychology Services Limited | Education | 2023 |
| Azukari Group Limited | Financial services | 2015 |
| Azukari Ltd | Wholesale & retail | 2011 |
| B & K Thomas (Holdings) Limited | Real estate | 1953 |
| B & K Thomas (Propco) Limited | Real estate | 2025 |
| B & K Thomas Limited | Real estate | 1991 |
| B & M Associates Limited | Information & communication | 1999 |
| B & R Woods Limited | Agriculture & fishing | 2003 |
| B F Aromatherapy Limited | Extraterritorial | 2012 |
| B Simms Engineering Ltd | Manufacturing | 2025 |
| B Simms Imports Ltd | Wholesale & retail | 2026 |
| B3 Solutions Ltd | Professional & scientific | 2006 |
| Baba Cleaning Services Ltd | Administrative & support | 2023 |
| Babolna BIO (UK) Limited | Extraterritorial | 2002 |
| Baby Swim Splash Ltd. | Arts & recreation | 2017 |
| Bakers Lane Management Ltd. | Households | 2012 |
| Bakt Group Ltd | Professional & scientific | 2026 |
| Balande Ltd | Hospitality | 2018 |
| Bankrank Services Limited | Other services | 2022 |
| Barghest Limited | Professional & scientific | 2018 |
| Bark Swimmingly Ltd | Professional & scientific | 2025 |
| Barmade Group Ltd | Information & communication | 2025 |
| Barnes Auto Repairs Ltd | Wholesale & retail | 2019 |
| Barnett Roofing Ltd | Administrative & support | 2011 |
| Barrow Property Lettings Ltd | Real estate | 2023 |
| Barry Randall Limited | Professional & scientific | 2017 |
| Bartels Construction Ltd | Wholesale & retail | 2019 |
| Base 8 Innovations Limited | Information & communication | 2016 |
| Base Formula Limited | Manufacturing | 2003 |
| Base Surveys Ltd | Construction | 2016 |
| Bashy Properties Ltd | Real estate | 2026 |
| BAT10 Limited | Real estate | 2020 |
| Batt Pilates & Sports Medicine Ltd | Health & social care | 2017 |
| Baubles and Bangles Limited | Wholesale & retail | 2014 |
| Baytree Electrical Limited | Manufacturing | 2026 |
| Baztel Ltd | Information & communication | 2013 |
| Bbdec Ltd | Administrative & support | 2024 |
| BE Kaos Limited | Professional & scientific | 2026 |
| BE Your Best YET Ltd | Other services | 2021 |
| Beacon Heights Management Co. (Loughborough) Ltd | Households | 2020 |
| Beam Electrics Limited | Construction | 2024 |
| Beam Stamp Ltd | Wholesale & retail | 2025 |
| Bearley Farm Green Energy Limited | Energy | 2017 |
| Became Ltd | Professional & scientific | 2023 |
| Beer Hub Ltd | Professional & scientific | 2016 |
| Begawan Ltd | Health & social care | 2020 |
| BEJ Broadcast Ltd | Information & communication | 2018 |
| Belfry Holdings Ltd | Financial services | 2023 |
| Bell Housing Limited | Real estate | 2020 |
| Belldart Limited | Extraterritorial | 1995 |
| Belmont Apparel Ltd | Wholesale & retail | 2026 |
| Belvoir Clinical Dental Laboratory Limited | Manufacturing | 2023 |
| Belvoir Equestrian Limited | Wholesale & retail | 2012 |
| Belvoir Equine Ltd | Administrative & support | 2015 |
| Belvoir Equine Veterinary Dental Services Ltd | Professional & scientific | 2022 |
| Belvoir Human Resources Limited | Professional & scientific | 2006 |
| Belvoir Vale IT Ltd | Information & communication | 2024 |
| Belvoir Vale Property Ltd | Real estate | 2020 |
| Belvoir Valley Solutions Limited | Professional & scientific | 2014 |
| Bencor Estates Limited | Construction | 2023 |
| Benskins Investments LLP | | 2016 |
| Bentons (Melton Mowbray) Limited | Real estate | 2013 |
| Bequality Ltd | Professional & scientific | 2018 |
| Bespoke Shutters & Blinds Limited | Manufacturing | 2010 |
| Best CUT Barbers (Melton) Ltd | Other services | 2019 |
| Best Sausage Company Ltd | Hospitality | 2025 |
| BESTSEO4U Ltd | Professional & scientific | 2017 |
| Beti Services Ltd | Transport & logistics | 2025 |
| Better Bargain Melton Ltd | Wholesale & retail | 2025 |
| Beyond Horizons MC Ltd | Information & communication | 2026 |
| BG Footage Ltd | Professional & scientific | 2024 |
| Big Commerce Ltd | Wholesale & retail | 2026 |
| Big Easy Printing Ltd | Manufacturing | 2021 |
| Big Osteopath Limited | Health & social care | 2000 |
| Bilgan Services Limited | Manufacturing | 2023 |
| Bingo Skip Ltd | Water & waste | 2011 |
| Bioly Limited | Professional & scientific | 2020 |
| Birstall Bag's | Health & social care | 2014 |
| Birth Year Watches Ltd | Wholesale & retail | 2018 |
| Biscottis Desserts Ltd | Hospitality | 2025 |
| Bishams (Berkshire) Limited | Wholesale & retail | 2021 |
| BJP Electrical Services Ltd | Construction | 2022 |
| BKW Machinery Ltd | Professional & scientific | 2021 |
| Black Box Developments Limited | Real estate | 2004 |
| Black Dog Music Limited | Wholesale & retail | 2016 |
| Black Dragon Games Ltd | Wholesale & retail | 2021 |
| Black Label Properties Ltd | Real estate | 2026 |
| Black Sapphire Enterprises Ltd | Wholesale & retail | 2018 |
| Black Stream Education Limited | Education | 2019 |
| Black Stream Technologies Limited | Information & communication | 2022 |
| Blencoe’S Property Solutions Ltd | Hospitality | 2026 |
| Blue IMP Games Ltd | Information & communication | 2025 |
| Blue Sun Energy Ltd | Construction | 2015 |
| Bluebelles Bows and Creations Ltd | Wholesale & retail | 2024 |
| Bluejack Productions Ltd | Health & social care | 2011 |
| Blueski Financial Synergy Ltd | Professional & scientific | 2022 |
| Bluestone Care Services Limited | Health & social care | 2025 |
| BME Installations Ltd | Construction | 2025 |