| Assetscape Limited | Information & communication | 2014 |
| Atlas Installations and Maintenance Limited | Construction | 2016 |
| Attract Mode Ltd | Information & communication | 2018 |
| Audit and Business Services Ltd | Professional & scientific | 2012 |
| AUM2737 Ltd | Professional & scientific | 2020 |
| Authud Limited | Information & communication | 2024 |
| Avalon Design Lighting Limited | Manufacturing | 2004 |
| Aviabuild Training Partners Ltd | Education | 2024 |
| AW Design Services Ltd | Professional & scientific | 2018 |
| AWP Properties Limited | Real estate | 2025 |
| Axelro Ltd | Information & communication | 2015 |
| Axis Design Engineering Ltd | Professional & scientific | 2014 |
| AYR Waste Management Group Limited | Financial services | 2025 |
| AYR Waste Management Limited | Water & waste | 2012 |
| Ayrshire Waste Management Limited | Water & waste | 2012 |
| Ayrshire Waste Solutions Ltd | Professional & scientific | 2000 |
| B.M. Polyco Limited | Manufacturing | 1978 |
| BAH Humbug Trading Ltd | Agriculture & fishing | 2019 |
| Bailey Builders Limited | Construction | 1998 |
| Bairsto Consulting Services Ltd | Professional & scientific | 2025 |
| Baker Electrical Solutions Ltd | Construction | 2020 |
| Ballast Phoenix Limited | Manufacturing | 2017 |
| Bammo Solutions Ltd | Professional & scientific | 2024 |
| Band 6 Properties Limited | Households | 2026 |
| Barber Cunnington Property Limited | Real estate | 2020 |
| Bardwell Mortgage Solutions Ltd | Financial services | 2016 |
| Barford Site Dumpers Ltd | Extraterritorial | 2010 |
| Barlow&Co Ltd | Professional & scientific | 2025 |
| Barretts Pubs Ltd | Hospitality | 2009 |
| BCS Fabrications Limited | Professional & scientific | 2013 |
| BE YOU Trition Limited | Other services | 2018 |
| Beak Studio Limited | Professional & scientific | 2021 |
| Bearstone Financial Ltd | Information & communication | 2010 |
| Beaumont Publishing Limited | Extraterritorial | 1996 |
| Beaverit Ltd | Information & communication | 2024 |
| Beeby Management Limited | Professional & scientific | 2020 |
| Beebys Limited | Administrative & support | 1989 |
| Beech Plastering Ltd | Construction | 2022 |
| Bella House Limited | Financial services | 2022 |
| Bembridge Consultancy Solutions Limited | Financial services | 2002 |
| Bembridge Risk & Resilience Limited | Professional & scientific | 2024 |
| Benlay Properties Limited | Real estate | 2023 |
| Bennetts Residential Properties Ltd | Real estate | 2023 |
| Bentley Building Ltd | Construction | 2012 |
| Berfeld Limited | Construction | 2015 |
| Bespoke Catering Vehicles Ltd | Manufacturing | 2025 |
| Best Food (UK) Limited | Real estate | 2003 |
| Bewit Limited | Professional & scientific | 2023 |
| Beyond the Blue Property Investments Ltd | Real estate | 2019 |
| Big Bananas Media Ltd | Information & communication | 2021 |
| Big Blue Clothing Limited | Wholesale & retail | 2014 |
| Big Spedition Ltd | Transport & logistics | 2024 |
| Bigfoot Leisure Limited | Arts & recreation | 2014 |
| Bipo Limited | Professional & scientific | 2007 |
| Birch Garden Services Ltd | Administrative & support | 2026 |
| Black Mountain Investments Ltd | Energy | 2025 |
| Blake Roofing Services Limited | Construction | 2022 |
| Blue Phoenix Group Limited | Manufacturing | 2017 |
| Blue Phoenix Limited | Manufacturing | 1996 |
| Blue Suit Property Ltd | Construction | 2024 |
| BMM Services (Lincs) Ltd | Professional & scientific | 2018 |
| BNU Raina Knyaginya Ltd | Education | 2021 |
| Bocon Ltd | Transport & logistics | 2021 |
| BOG Dog Running Limited | Wholesale & retail | 2021 |
| Bold Soul Brands Ltd | Wholesale & retail | 2025 |
| Booker Accounting Solutions Ltd | Professional & scientific | 2021 |
| Boss Cabins Limited | Manufacturing | 2009 |
| Boston Lock Cafe Limited | Hospitality | 2018 |
| Bourn Convenience Store Limited | Wholesale & retail | 2024 |
| Bourne 2 Hire Cars Ltd | Administrative & support | 2019 |
| Bourne 2 Hire Ltd | Administrative & support | 2013 |
| Bourne Accommodation Limited | Extraterritorial | 2010 |
| Bourne Arts and Community Trust Limited | Other services | 1999 |
| Bourne Bookshop Limited | Wholesale & retail | 2022 |
| Bourne Cabs Ltd | Transport & logistics | 2025 |
| Bourne Chicken Hub Ltd | Hospitality | 2026 |
| Bourne Decorating Services Ltd | Construction | 2022 |
| Bourne Earwax Clinic Ltd | Health & social care | 2025 |
| Bourne Electrical and Plumbing Supplies Limited | Wholesale & retail | 2010 |
| Bourne Golf Centre Limited | Arts & recreation | 2008 |
| Bourne Grammar School | Education | 2011 |
| Bourne Kebabs Ltd | Hospitality | 2024 |
| Bourne Skip Hire and Recycling Limited | Water & waste | 2002 |
| Bourne Sourcing Ltd | Real estate | 2024 |
| Bourne to Shop Ltd | Wholesale & retail | 2022 |
| Bourne Toys Ltd | Wholesale & retail | 2022 |
| BOURNE2STORE Limited | Transport & logistics | 2015 |
| Bowmans Workshop Ltd | Manufacturing | 2022 |
| BP2023 Limited | Administrative & support | 2005 |
| Bracknell Roofing South Limited | Construction | 2022 |
| Branch Bros. Limited | Wholesale & retail | 1967 |
| British Boer and Meat Goat Association | Other services | 2022 |
| Brooke Lodge Residents Management Company Limited | Real estate | 2005 |
| Brooks Brickworks Ltd. | Construction | 2004 |
| Bruce the Builder UK Limited | Construction | 2024 |
| Brunswald Properties Limited | Construction | 2015 |
| Bruny Limited | Real estate | 2010 |
| BSH Recycling Limited | Real estate | 2017 |
| Bull Agri Ltd | Wholesale & retail | 2018 |
| Burtons Automotive Ltd | Wholesale & retail | 2023 |