| Build (NW) Limited | Information & communication | 2015 |
| Build Force Property (Chester) Limited | Real estate | 2021 |
| Build MDN Limited | Transport & logistics | 2025 |
| Buildersbuyer Ltd | Wholesale & retail | 2023 |
| Builderwatch Ltd | Administrative & support | 2021 |
| Building Fabric Solutions Limited | Construction | 2019 |
| Building Wildlife Trust | Administrative & support | 2010 |
| Bulut Ltd Group Ltd | Manufacturing | 2023 |
| Bumblebee Growers Ltd | Agriculture & fishing | 2023 |
| Bumblebee Homes Ltd | Real estate | 2020 |
| Bump Start Properties Ltd | Real estate | 2025 |
| Bunbury Agency Limited | Administrative & support | 2003 |
| Bunbury Arms Stoak Ltd | Hospitality | 2024 |
| Bundy's Electrical & Safety Testing Limited | Construction | 2003 |
| Bunica Limited | Real estate | 2019 |
| Burfield FP Holdings Ltd | Financial services | 2022 |
| Burleigh Holistic Therapies Ltd | Health & social care | 2020 |
| Burnoutai Ltd | Information & communication | 2025 |
| Burns Properties Limited | Hospitality | 2013 |
| Burrow Property Limited | Real estate | 2018 |
| Burrow&Co Limited | Professional & scientific | 2019 |
| Burton Electrical Services Limited | Construction | 2025 |
| Bush Fits Ltd | Construction | 2022 |
| Business & Tax Loans Limited | Financial services | 2024 |
| Business Comparison Group Limited | Financial services | 2020 |
| Business Comparison Ltd | Professional & scientific | 2016 |
| Business Homes (Wakefield) Limited | Real estate | 2004 |
| Business Homes North (West) Limited | Construction | 2005 |
| Business Lists U.K. Limited | Information & communication | 1987 |
| Business Modelling Applications Limited | Extraterritorial | 2022 |
| Business Modelling Associates UK Limited | Professional & scientific | 2013 |
| Business of Emotions Ltd | Professional & scientific | 2000 |
| Business Reform Limited | Professional & scientific | 2011 |
| Business Safety Solutions Limited | Professional & scientific | 2020 |
| Business Sports Consultants Ltd | Arts & recreation | 2018 |
| Business Support Chester Limited | Administrative & support | 2025 |
| Business Transitions Ltd | Professional & scientific | 2026 |
| Busybus Ltd | Administrative & support | 2002 |
| BUT I Buried YOU Limited | Information & communication | 2024 |
| Butah En-Semma Ltd | Hospitality | 2022 |
| Butterbache Ltd | Wholesale & retail | 2024 |
| Buttercups Day Nursery (Flintshire) Ltd | Education | 2011 |
| Butterfly Living Ltd | Real estate | 2025 |
| Bvpr Quantity Surveying Ltd | Professional & scientific | 2025 |
| BWB Rating Limited | Professional & scientific | 2015 |
| Bwtw Limited | Professional & scientific | 2023 |
| BXB Wolsingham Limited | Construction | 2017 |
| BY AMG Limited | Other services | 2025 |
| BY George Marketing Ltd | Professional & scientific | 2016 |
| Bydesign GR. Limited | Professional & scientific | 2025 |
| BYE Pass Management Group Limited | Households | 2024 |
| Bykala Limited | Other services | 2006 |
| Bynevemistry Ltd | Professional & scientific | 2026 |
| Byott Limited | Administrative & support | 2025 |
| C & a Hayling Ltd | Arts & recreation | 2025 |
| C & J Investment Properties Limited | Real estate | 2018 |
| C & M Nicholson Associates Ltd | Professional & scientific | 2018 |
| C & S Care Services Ltd | Other services | 2000 |
| C a Fletcher Holdings Limited | Financial services | 2026 |
| C a Fletcher Investments Limited | Real estate | 2026 |
| C a Heritage Ltd | Professional & scientific | 2019 |
| C Boggia Ltd | Professional & scientific | 2026 |
| C D & a Services Ltd | Wholesale & retail | 2016 |
| C E Legal Limited | Professional & scientific | 2014 |
| C G Racing Ltd | Arts & recreation | 2024 |
| C J Payne(Home Improvements) Ltd | Construction | 2007 |
| C Salt Property Limited | Real estate | 2026 |
| C Thompson and SON Transport Limited | Transport & logistics | 2020 |
| C&K Consultancy Ltd | Arts & recreation | 2020 |
| C&K Trading London Limited | Hospitality | 2020 |
| C&L Rzepinski Ltd | Wholesale & retail | 2021 |
| C. Fatboys Ltd | Hospitality | 2022 |
| C.A. Morgan Limited | Construction | 1999 |
| C.C.A. (U.K.) Advisory Services Limited | Professional & scientific | 1979 |
| C.E.P.D. Limited | Education | 2012 |
| C.R.F. Swimming Pools Limited | Construction | 2003 |
| C3 Customer Solutions Ltd | Professional & scientific | 2005 |
| C3I (Europe) Limited | Other services | 2004 |
| C3X Ltd | Construction | 2024 |
| C6 Consulting Ltd | Professional & scientific | 2025 |
| CAB Enterprise Limited | Wholesale & retail | 2021 |
| Cabin on the Lake Limited | Hospitality | 2007 |
| Cablify Limited | Information & communication | 2024 |
| Cabuk Cars Limited | Transport & logistics | 2017 |
| Cadagio Ltd | Other services | 2014 |
| Cadence Core Consultancy Ltd | Information & communication | 2025 |
| Cadify Limited | Extraterritorial | 2009 |
| Cadre Bond Limited | Administrative & support | 2024 |
| Cadwaladr Sons Ltd | Agriculture & fishing | 2013 |
| Cadwallader Homes Limited | Construction | 2023 |
| CAE Mynach (Treuddyn) Management Company Limited | Households | 2023 |
| Caeapps Ltd | Extraterritorial | 2019 |
| Caer Estates Limited | Real estate | 2017 |
| Caer Investments Limited | Real estate | 2023 |
| Cafe Culture Cheshire Limited | Hospitality | 2016 |
| Cafe.Com Coffee Limited | Hospitality | 2013 |
| Caitlin Jane Consultancy Limited | Public administration | 2023 |
| CAJ & Sons Ltd | Households | 2023 |
| Cakin Barbering & Grooming Limited | Other services | 2020 |
| Calco Properties Limited | Real estate | 2006 |