| Brunel Court Management Company (South West) Limited | Households | 2006 |
| Brunel Heating Limited | Construction | 2019 |
| Brunel Medical Services Limited | Health & social care | 2010 |
| Brunel Mews Saltash Management Company Limited | Households | 2006 |
| Brunel Property Investments SW Limited | Real estate | 2024 |
| Brunning Host Limited | Hospitality | 1999 |
| Brunswick Limited | Real estate | 2006 |
| Brunswick Parr Limited | Real estate | 2025 |
| Bryant Commercial Survey Services Ltd | Administrative & support | 2017 |
| Bryant Interiors (Plymouth) Limited | Professional & scientific | 2015 |
| BSB Refinishing Limited | Other services | 2017 |
| BTB Couriers Limited | Transport & logistics | 2001 |
| Bubbas (Plympton) Ltd | Arts & recreation | 2018 |
| Bubbas (UK) Ltd | Arts & recreation | 2014 |
| Bubi Ventures Limited | Wholesale & retail | 2025 |
| Bucharest Market Plymouth Ltd | Wholesale & retail | 2025 |
| Buckclose Limited | Construction | 1972 |
| Buckland Management Company Limited | Administrative & support | 2006 |
| Buddha Civils & Construction Ltd | Construction | 2022 |
| Buddha Consulting Ltd | Professional & scientific | 2024 |
| Buddha Group Ltd | Financial services | 2022 |
| Buddha Property Ltd | Real estate | 2022 |
| Buddha Utilities Ltd | Construction | 2022 |
| Buddhas Hands Wellness Ltd | Health & social care | 2024 |
| Buddies Childcare CIC | Education | 2011 |
| Budding Ventures Ltd | Other services | 2018 |
| Bude Smoke and Vape Ltd | Wholesale & retail | 2018 |
| Budget Locksmiths (SW) Ltd | Manufacturing | 2025 |
| Buffit Limited | Wholesale & retail | 2024 |
| Buhush Ltd | Hospitality | 2020 |
| Buiildsafe (UK) Ltd | Other services | 2018 |
| Build South West Limited | Construction | 2022 |
| BUILDATRONIX3D Ltd | Manufacturing | 2024 |
| Building + Construction Services (SW) Ltd. | Construction | 2012 |
| Building Brands Marketing Ltd | Other services | 2025 |
| Buildx (Group) Ltd | Construction | 2022 |
| Buildx (SW) Ltd | Construction | 2020 |
| Buildx Properties Ltd | Construction | 2024 |
| Built Right Developments Ltd | Construction | 2025 |
| Builtech Ltd | Construction | 2017 |
| Bull & Bush Limited | Hospitality | 2022 |
| Bulldog Accountancy Services Ltd | Professional & scientific | 2022 |
| Bulldog Engineering Ltd | Professional & scientific | 2019 |
| Bulletproof Brewing Ltd | Manufacturing | 2016 |
| Bulletstage Ltd | Administrative & support | 2018 |
| Bumblebee Commercial Ltd | Real estate | 2020 |
| Burch Offshore Ltd | Professional & scientific | 2019 |
| Burcombe Group SW Limited | Financial services | 2021 |
| Burcombe Haulage Limited | Transport & logistics | 1999 |
| Burdettholdings Limited | Administrative & support | 2025 |
| Burger and Bones BBQ Ltd | Hospitality | 2018 |
| Burgess Electrical Solutions Limited | Construction | 2007 |
| Burleigh Manor Management Company Limited | Households | 1992 |
| Burley Consultants (South West) Limited | Professional & scientific | 2010 |
| Burlington Lane Investments Ltd | Real estate | 2016 |
| Burlington Social Work Services Ltd | Health & social care | 2023 |
| Burnetts Auto Care Limited | Wholesale & retail | 2019 |
| Burrington Way Garage Limited | Wholesale & retail | 2006 |
| Burton Solutions Ltd | Professional & scientific | 2015 |
| Burton's Sentry Ltd | Construction | 2018 |
| Bush Stables Limited | Agriculture & fishing | 2013 |
| Bushra Property Management Ltd | Real estate | 2016 |
| Business Computing and Network Services Limited | Information & communication | 1999 |
| Business Mentors South West Ltd | Professional & scientific | 2005 |
| Business Success HR Ltd | Administrative & support | 2020 |
| Business Success Marketing Ltd | Professional & scientific | 2019 |
| Business Success SW Ltd | Professional & scientific | 2015 |
| Busy Body Care Limited | Professional & scientific | 2000 |
| Busybee Development Ltd | Real estate | 2022 |
| Butterfield Motor Werks Ltd | Wholesale & retail | 2018 |
| Butterflies & Roses Ltd | Wholesale & retail | 2020 |
| Buzz Physique Apparel Limited | Manufacturing | 2019 |
| BW Properties (Plymouth) Limited | Households | 2012 |
| BWA Architecture Limited | Professional & scientific | 2021 |
| BWA Consultants Limited | Administrative & support | 2022 |
| BY Charles Ltd | Manufacturing | 2018 |
| BY the Buy Lets Limited | Real estate | 2019 |
| Bybaefii Ltd | Other services | 2026 |
| BYC Designs UK Limited | Manufacturing | 2021 |
| Bynd Collective Ltd | Information & communication | 2018 |
| C & a New Build Construction Limited | Real estate | 2019 |
| C & a Partnership Ltd | Information & communication | 2018 |
| C & a Plymouth Ltd | Real estate | 2025 |
| C & C (SW) Limited | Energy | 2014 |
| C & D Electrical Plus Limited | Manufacturing | 2012 |
| C & D Nurseries Ltd | Agriculture & fishing | 2025 |
| C & D Telecoms Plus Limited | Information & communication | 2015 |
| C & E Properties Ltd | Real estate | 2022 |
| C & M Services (South West) Limited | Administrative & support | 2011 |
| C & N Snowdon Properties Ltd | Real estate | 2025 |
| C . M . Construction 2020 Limited | Construction | 2019 |
| C 100 Callington Ltd | Hospitality | 2024 |
| C B E (South West) Ltd | Construction | 2006 |
| C C a D S Limited | Professional & scientific | 2003 |
| C D C Groundworks Ltd | Construction | 2008 |
| C F S Engineering Ltd | Construction | 2015 |
| C H Barons Ltd | Construction | 2015 |
| C L B Consultancy Ltd | Information & communication | 2021 |
| C L B Property Services Ltd | Real estate | 2021 |
| C M D Remote Services Limited | Public administration | 2008 |