| Brimax Services Ltd | Wholesale & retail | 2021 |
| Brimorta Ltd | Real estate | 2025 |
| Brinklow Close Management Company Limited | Real estate | 2015 |
| Brit Removals Ltd | Transport & logistics | 2026 |
| Britax Childcare Group Limited | Professional & scientific | 2003 |
| Britax Childcare Holdings Limited | Professional & scientific | 2005 |
| Britax Childcare Investments Limited | Professional & scientific | 1963 |
| Britax Childcare Limited | Professional & scientific | 2000 |
| Britax Childcare Pensions Trust Limited | Financial services | 2006 |
| Britax Excelsior Limited | Manufacturing | 1934 |
| Britax Group Limited | Professional & scientific | 2010 |
| British FLY Reels Limited | Transport & logistics | 1993 |
| Brochet Limited | Information & communication | 1996 |
| Broddie's Ltd | Wholesale & retail | 2022 |
| Brogans Paranormal Seekers Ltd | Administrative & support | 2024 |
| Brooker Electronics Solutions Ltd | Manufacturing | 2021 |
| Brooklands Driving Ltd | Education | 2019 |
| Brooks, Crownhill Patternmakers Limited | Manufacturing | 1962 |
| Brookwood Events Limited | Administrative & support | 2012 |
| Browny Logistics Ltd | Transport & logistics | 2020 |
| Brucha UK Ltd | Wholesale & retail | 2025 |
| Brunel Integrated Engineering Limited | Professional & scientific | 2026 |
| Brunos Coffee Shop Ltd | Hospitality | 2020 |
| Brzostek Property Ltd | Real estate | 2019 |
| BSC Power Engineering Ltd | Manufacturing | 2022 |
| BT Housing Ltd | Real estate | 2024 |
| Bucks&Doe Hairdressing Limited | Other services | 2021 |
| Buddys Autos Ltd | Professional & scientific | 2019 |
| Bull & Co. Solicitors LLP | | 2015 |
| Bull by the Horns Limited | Professional & scientific | 2013 |
| Bulpitt Print Limited | Manufacturing | 1998 |
| Bumbah Ltd | Other services | 2023 |
| Buno Enterprise Limited | Health & social care | 2022 |
| Burden-Brown Property Management Ltd | Real estate | 2021 |
| Burgers & Co Andover Ltd | Hospitality | 2021 |
| Burgon Environmental Solutions Ltd | Professional & scientific | 2012 |
| Burgos Pet World Ltd | Wholesale & retail | 2016 |
| Burlison Ltd | Information & communication | 2005 |
| Bushnell Groundworks Ltd | Construction | 2009 |
| Business Ascent Consulting Ltd | Education | 2014 |
| Butler Financial Solutions Ltd | Financial services | 2026 |
| Butterflies Home Care Ltd | Health & social care | 2011 |
| Butterflies Speech, Language & Communication Services Limited | Health & social care | 2022 |
| Bvlr Limited | Wholesale & retail | 2021 |
| Byteful Tech Ltd | Information & communication | 2025 |
| Bytehogs Limited | Information & communication | 2020 |
| C & M D.I.Y Centre Ltd | Wholesale & retail | 2007 |
| C and K Contractors Ltd | Construction | 2021 |
| C C & SON Construction Ltd | Construction | 2014 |
| C H Property Services Ltd | Construction | 2026 |
| C J Flooring (Andover) Limited | Wholesale & retail | 2021 |
| C P E Hooper (Agriculture) Ltd | Agriculture & fishing | 2023 |
| C. Guilford Limited | Extraterritorial | 2010 |
| C.A. Stevens and Sons (Transport) Limited | Wholesale & retail | 1978 |
| C.C.C Biohazard Specialists Ltd | Administrative & support | 2026 |
| C.E.S Hospitality Ltd | Hospitality | 2025 |
| C.S. Hunt & SON (Enham) Limited | Agriculture & fishing | 1958 |
| C13 Fitness Ltd | Arts & recreation | 2023 |
| Caelum Training Limited | Transport & logistics | 2014 |
| Caffe Espresso Bar Ltd | Hospitality | 2003 |
| Cali Fitness UK Limited | Arts & recreation | 2024 |
| Calver Parties Ltd | Hospitality | 2023 |
| Camberdent Ltd. | Health & social care | 2009 |
| Cambridge Sciences Limited | Manufacturing | 2011 |
| Camigo Travel Ltd | Administrative & support | 2024 |
| Camistar New Build Construction Ltd | Wholesale & retail | 2024 |
| Canter Group Ltd | Professional & scientific | 2025 |
| Capes Farms Limited | Agriculture & fishing | 2021 |
| Caprighia Ltd | Information & communication | 2026 |
| Cara (Topco) Limited | Financial services | 2018 |
| Carbon Sink Ltd | Extraterritorial | 2024 |
| Cardew & Co. (Oxford) Limited | Wholesale & retail | 1983 |
| Cardew Holdings Limited | Professional & scientific | 2015 |
| Cardons Direct Ltd | Wholesale & retail | 2019 |
| Careful Carriers Ltd | Transport & logistics | 2024 |
| Carewise Innovations Ltd | Information & communication | 2023 |
| Cargojet Limited | Transport & logistics | 2026 |
| Cargowise Global Limited | Wholesale & retail | 2024 |
| Cargowise Solutions Limited | Wholesale & retail | 2015 |
| Cariad Properties Ltd | Real estate | 2016 |
| Caring Clearances Ltd | Water & waste | 2020 |
| Carisma Private Hire Ltd | Transport & logistics | 2015 |
| Carpenters Court Vincent Drive M.C. Limited | Households | 2008 |
| Carr's Corner Management Company Limited | Real estate | 2016 |
| Carrera Sport Ltd | Wholesale & retail | 2012 |
| Carrott Interiors Limited | Construction | 2025 |
| Carter Executive Recruitment Ltd | Administrative & support | 2020 |
| Cartridge and Personalized Print World (Andover) Ltd | Wholesale & retail | 2012 |
| Carvo Ltd | Wholesale & retail | 2025 |
| Casl UK Ltd | Wholesale & retail | 2009 |
| Castle Mews Apartments Ltd | Hospitality | 2022 |
| Castledown FM Ltd | Information & communication | 2008 |
| Castrejo Ltd | Extraterritorial | 2018 |
| Cat-Uxo Ltd | Information & communication | 2012 |
| Catchmentai Limited | Information & communication | 2025 |
| Cathedral Freehold Limited | Households | 2007 |
| Cawp Ltd | Professional & scientific | 2022 |
| CB Aesthetics Limited | Other services | 2024 |
| CBN Lettings Limited | Real estate | 2023 |
| CC 4 (2011) Limited | Professional & scientific | 2010 |