| Burj Capital Ltd | Financial services | 2026 |
| Burj Housing Ltd | Real estate | 2026 |
| Burke Family Holding Company Limited | Financial services | 2021 |
| Burmor Developments 2010 Limited | Construction | 2010 |
| Burmor Group Ltd | Professional & scientific | 2018 |
| Burnhurst Limited | Health & social care | 2009 |
| Burnout Media Limited | Administrative & support | 2015 |
| Burrowmoor Consulting Limited | Real estate | 2006 |
| Bursting With Adventure CIC | Education | 2024 |
| Burton Foods Ltd | Hospitality | 2026 |
| BUS and Coach Repairs Ltd | Wholesale & retail | 2020 |
| Bushfield Surgery Limited | Hospitality | 1999 |
| Business Advice Bureau (Peterborough) Ltd | Professional & scientific | 2021 |
| Business Connector International (UK) Limited | Professional & scientific | 2003 |
| Business Engineering Services Ltd | Information & communication | 2024 |
| Business GPU Ltd | Wholesale & retail | 2025 |
| Business Improvement Solutions Ltd | Professional & scientific | 2025 |
| Business Interiors (GB) Ltd | Manufacturing | 2003 |
| Business Iron Development Ltd | Manufacturing | 2021 |
| Business Link Consultancy Limited | Professional & scientific | 2023 |
| Business Management Software Limited | Information & communication | 1990 |
| Business of Giedrius Limited | Construction | 2024 |
| Business Perpetual Ltd | Administrative & support | 2011 |
| Business Process Consultancy Ltd | Professional & scientific | 2016 |
| Business Productivity Solutions Limited | Information & communication | 2015 |
| Business Utilities Provider Ltd | Wholesale & retail | 2024 |
| Businesswatch Guarding Services Limited | Administrative & support | 2018 |
| Bust Limited | Arts & recreation | 2020 |
| Buster and Punch Limited | Wholesale & retail | 2012 |
| Busy Bunnies Ashfield Ltd | Education | 2024 |
| Busy Bunnies Braybrook Ltd | Health & social care | 2022 |
| Busy Bunnies Hampton Water Ltd | Education | 2022 |
| Busy Bunnies Huthwaite Ltd | Education | 2024 |
| Busy Bunnies Kirkby Ltd | Education | 2024 |
| Busy Bunnies Nurseries Ltd | Education | 2024 |
| Busy Bunnies Nursery Ltd | Education | 2012 |
| Busz-Tom Ltd | Transport & logistics | 2026 |
| Butcher Bayley Architects Limited | Professional & scientific | 2016 |
| Butcher Bayley Developments Limited | Construction | 2026 |
| Butcher Race Engineering Ltd | Professional & scientific | 2020 |
| Butcher to Plate Ltd | Hospitality | 2026 |
| Butler Symonds Ltd | Financial services | 2012 |
| Butler Symonds Trading Ltd | Wholesale & retail | 2023 |
| Butlers Bakes Ltd | Manufacturing | 2025 |
| Butlers Meadow Residents Company Limited | Households | 2000 |
| Buttercross Meadow Somerton Management Company Limited | Households | 2022 |
| Buttercup Barn Farm Holdings Limited | Real estate | 2026 |
| Butterworth Roofing Ltd | Construction | 2025 |
| Buttressed Beast Ltd | Professional & scientific | 2019 |
| Butts Croft Limited | Health & social care | 1984 |
| Buybulk Limited | Construction | 1966 |
| Buymain Limited | | 1988 |
| Buzz RAW Honey Co Ltd | Wholesale & retail | 2025 |
| Buzza Trans Ltd | Construction | 2020 |
| Buzzard Leisure Limited | Administrative & support | 1996 |
| Buzzbees Group Limited | Administrative & support | 2021 |
| BVT Healthcare Ltd | Health & social care | 2023 |
| BW Leasing Limited | Administrative & support | 2017 |
| BW Property Nottingham Ltd | Hospitality | 2024 |
| Bwarehouse Ltd | Real estate | 2021 |
| Bwarehouse Management Ltd | Real estate | 2023 |
| BWP (TV) Limited | Construction | 2001 |
| BY June Howard Limited | Other services | 2019 |
| By.Khansa Ltd | Wholesale & retail | 2026 |
| BYT Solutions Ltd | Wholesale & retail | 2019 |
| Byteignite Services Ltd | Information & communication | 2019 |
| Bytelogic Ltd | Information & communication | 2024 |
| Byteview Solutions Limited | Information & communication | 1997 |
| Byzantium Security Solutions Limited | Administrative & support | 2012 |
| BZH Financial Ltd | Financial services | 2024 |
| C & a Employment Limited | Administrative & support | 2022 |
| C & F Building Services Ltd | Construction | 2015 |
| C & J Motor Rentals Ltd | Wholesale & retail | 2021 |
| C & N Fabrications Limited | Manufacturing | 2010 |
| C & P Motor Services Limited | Wholesale & retail | 2003 |
| C Beauty by Cait Ltd | Other services | 2025 |
| C C Networks Limited | Information & communication | 2019 |
| C D Brace & Sons Limited | Agriculture & fishing | 2012 |
| C E L Leadwork Contracts Limited | Manufacturing | 1991 |
| C F Gill Properties Limited | Financial services | 2010 |
| C F M D Limited | Professional & scientific | 2018 |
| C Grecu Ltd | Transport & logistics | 2020 |
| C I Consultancy and Introductions Ltd | Financial services | 2013 |
| C J Kelly Associates Limited | Professional & scientific | 1997 |
| C J Kelly International Ltd | Professional & scientific | 2014 |
| C J Westcroft Limited | Wholesale & retail | 2015 |
| C J Woollard Electrical Limited | Construction | 2013 |
| C K Bamboo Limited | Manufacturing | 2025 |
| C N Technical Services Limited | Wholesale & retail | 2009 |
| C Normington Plastering Limited | Construction | 2021 |
| C P Rentals Ltd | Administrative & support | 2024 |
| C R Hunter Brickwork Ltd | Construction | 2022 |
| C S Heating Specialists Ltd | Construction | 2019 |
| C Small Solutions Limited | Information & communication | 2015 |
| C Y C Practice Ltd | Health & social care | 2022 |
| C&C Empathy Training Ltd | Other services | 2014 |
| C&G Craft Limited | Wholesale & retail | 2024 |
| C&H Country Homes Ltd | Construction | 2023 |
| C&L Bacon Properties Ltd. | Real estate | 2021 |
| C&M Properties (Lincs) Limited | Real estate | 2024 |