| AVR Electrical Ltd | Manufacturing | 2025 |
| Awayhome Limited | Administrative & support | 2013 |
| Aztec Electrical (SW) Limited | Construction | 2020 |
| Azzy Kebab Company Limited | Hospitality | 2022 |
| B20 Wessex Limited | Professional & scientific | 2003 |
| Badbury House Consulting Ltd | Professional & scientific | 2020 |
| Baff (2006) Limited | Other services | 2006 |
| Bagnall Roofing Ltd | Construction | 2025 |
| Balance Your Books (South West) Limited | Professional & scientific | 2015 |
| Bar 2 Hire Ltd | Hospitality | 2020 |
| Barbastelle Ltd | Manufacturing | 2018 |
| BARDEN2ZERO Services Limited | Information & communication | 2013 |
| Bassett's Consultancy Ltd | Information & communication | 2016 |
| Bath Heritage Tiling Ltd | Construction | 2021 |
| Bath Hydrotherapy Limited | Professional & scientific | 2017 |
| Bath Leather Goods Limited | Wholesale & retail | 2015 |
| Bath Road Residents Management Company Limited | Real estate | 2008 |
| BDM Structures Ltd | Professional & scientific | 2018 |
| BE Here NOW Tattooing and Yoga Limited | Other services | 2014 |
| Beard Excavations Ltd | Administrative & support | 2024 |
| Beautiful Human Designs Ltd | Wholesale & retail | 2024 |
| Beech Spraying & Decorating Limited | Construction | 2021 |
| Bella and Ollie Art Ltd | Professional & scientific | 2026 |
| Bella Productions Ltd | Wholesale & retail | 2025 |
| Bellstone Consultancy Group Limited | Professional & scientific | 2010 |
| BEN David Limited | Construction | 2013 |
| Benchmark Building Solutions Ltd | Construction | 2018 |
| Bennetts Bathrooms Limited | Construction | 2017 |
| Bernard Morley Limited | Professional & scientific | 2021 |
| Bernie Inc Ltd | Manufacturing | 2024 |
| Berryfield Services Ltd | Agriculture & fishing | 2022 |
| Best Beverage Procurment Limited | Wholesale & retail | 2019 |
| BGL Rieber Limited | Wholesale & retail | 1987 |
| Bhaji Bites Ltd | Administrative & support | 2019 |
| Biba HSE Consultancy Ltd | Professional & scientific | 2026 |
| Big TEK Ltd | Information & communication | 2015 |
| Bike and Bean Limited | Hospitality | 2021 |
| Bisnit Limited | Wholesale & retail | 2023 |
| BJB Home Improvements Limited | Construction | 2006 |
| Black Sheep Timber Framing Ltd | Construction | 2005 |
| Blackhawk Services Ltd | Professional & scientific | 2015 |
| Blast Clean Systems UK Limited | Extraterritorial | 2014 |
| Blindspot Driving Limited | Education | 2025 |
| Bluemay International Limited | Wholesale & retail | 2001 |
| Bluemay Limited | Manufacturing | 1973 |
| Bluemay Multicap Limited | Extraterritorial | 1986 |
| Bluemay Weston Limited | Manufacturing | 1999 |
| BM Logistics Solutions Ltd | Transport & logistics | 2023 |
| BMA Properties ( South West) Ltd | Construction | 2022 |
| BMT Stone Carving and Fixing Limited | Manufacturing | 2017 |
| Bobatee Ltd | Hospitality | 2024 |
| Boilercare Wilts Limited | Construction | 2025 |
| Bolter's Woodburner Installations Limited | Construction | 2025 |
| Boomerang Land & Properties Ltd | Arts & recreation | 2009 |
| Bordomax Ltd | Hospitality | 2020 |
| Bound Rings Ltd | Wholesale & retail | 2025 |
| Bowerhill Machinery Services Ltd | Manufacturing | 2018 |
| Bowerhill Management Company Limited | Households | 2013 |
| Bowlamania Limited | Wholesale & retail | 2011 |
| BP Bodyworks Ltd | Wholesale & retail | 2014 |
| Brampton Financial Management Ltd | Financial services | 2006 |
| Breakthrough Trowbridge | Health & social care | 2009 |
| Bridges Carpentry Ltd | Construction | 2023 |
| Bright Ideas Electrical and Design Ltd | Construction | 2016 |
| Brighter Futures Counselling C.I.C. | Health & social care | 2025 |
| British Assistive Technology Association Limited | Other services | 2010 |
| Broad Lane Industrial Park Limited | Energy | 2012 |
| Broad Lane Yard Ltd | Real estate | 2018 |
| Brokenhouse Consulting Ltd | Information & communication | 2011 |
| Brooks Carpentry Ltd | Construction | 2024 |
| Brooksie-Net Ltd | Information & communication | 2020 |
| Broughton Court (Melksham) Management Company Limited | Households | 2018 |
| Broughton Farms Ltd | Agriculture & fishing | 2017 |
| Broughton Farms Property Limited | Agriculture & fishing | 2023 |
| Broughton Group Limited | Financial services | 2023 |
| Broughton Storage Limited | Transport & logistics | 2018 |
| Broughton Transport Solutions Ltd | Transport & logistics | 2011 |
| Brunel Engineering Services Limited | Wholesale & retail | 2009 |
| Brush & Bond Ltd | Arts & recreation | 2025 |
| Bryant Brickwork Ltd | Construction | 2026 |
| Buffalo Bolts Limited | Extraterritorial | 1986 |
| Bupton Land Limited | Professional & scientific | 2010 |
| Bupton Project Management Limited | Construction | 2012 |
| BV Engineering Services Limited | Professional & scientific | 2025 |
| C S Property Melksham Ltd | Professional & scientific | 2011 |
| C-Pen Limited | Wholesale & retail | 2023 |
| Cabot Trading Ltd | Wholesale & retail | 2025 |
| Callies Mate Wine Ltd | Wholesale & retail | 2024 |
| Camera DEN Limited | Professional & scientific | 2007 |
| Canon Properties Melksham Ltd | Real estate | 2015 |
| Carbon Reduction Solutions Limited | Professional & scientific | 2023 |
| Carmatch UK Limited | Wholesale & retail | 1998 |
| Carols Cabs Limited | Transport & logistics | 2014 |
| Caron Nosek Limited | Wholesale & retail | 2003 |
| Caseinhand Limited | Information & communication | 2011 |
| Castellum Healthcare Limited | Health & social care | 2023 |
| Cayrus World of Finishing Ltd | Wholesale & retail | 2014 |
| CC Technologies Ltd | Information & communication | 2021 |
| Cedar and Stone Properties Ltd | Real estate | 2026 |
| Centreline Resourcing Ltd | Administrative & support | 2020 |