| Bespoke Travel Group Limited | Administrative & support | 2026 |
| Best Places Holidays and Travel Limited | Administrative & support | 2012 |
| Beth Whiting Ltd | Health & social care | 2019 |
| Beyond the Ascent Ltd | Arts & recreation | 2021 |
| BF5 Holdings Limited | Financial services | 2025 |
| Bicb Limited | Professional & scientific | 2014 |
| Big Adventure (Education) Limited | Education | 2019 |
| Big Step Solutions Limited | Construction | 2012 |
| Bigland Hall Caravan Park Limited | Hospitality | 1976 |
| Bigland Properties Limited | Financial services | 1974 |
| Biglands Joinery Limited | Construction | 2002 |
| Biketreks Limited | Wholesale & retail | 2002 |
| Biltong Buddy Ltd | Manufacturing | 2025 |
| Biological Dentistry Limited | Health & social care | 2020 |
| Birk Hagg Management Company Limited | Households | 2010 |
| Birks Farm New Hutton Management Company Limited | Households | 2000 |
| BJJ Camps Ltd | Other services | 2021 |
| BKS (Rawsons) Limited | Professional & scientific | 2016 |
| Black Magic Metalworks Ltd | Manufacturing | 2023 |
| Blackdog Landscaping Ltd | Agriculture & fishing | 2022 |
| Blackthorn Close Management Company Limited | Households | 2022 |
| Blade & Rose Limited | Wholesale & retail | 2013 |
| Blencathra Hydro Limited | Energy | 2015 |
| Blossom Tree Property Ltd | Real estate | 2026 |
| BLS Hospitality Limited | Hospitality | 2023 |
| Blue Cooling Engineering Services Limited | Construction | 2026 |
| Blue Cooling Ltd | Manufacturing | 2006 |
| Blue Labrador Limited | Financial services | 2021 |
| Blue Quadrant Coaching Limited | Professional & scientific | 2020 |
| Blue Sett Ltd | Agriculture & fishing | 2020 |
| Blue Star Taxis (Kendal) Limited | Transport & logistics | 2008 |
| Bluestone Worktops Limited | Wholesale & retail | 2015 |
| Boardcrest Ltd | Information & communication | 2010 |
| Bobbin Mill Agricultural Limited | Agriculture & fishing | 2020 |
| Bolton & Holden Property Maintenance Services Ltd | Real estate | 2023 |
| Bombay Bistro Restaurant & Takeaway Ltd | Hospitality | 2025 |
| Bombay Bistro Restaurant and Catering Ltd | Hospitality | 2026 |
| Booksmart Accounting Limited | Professional & scientific | 2021 |
| Bootleggers Kendal Limited | Hospitality | 2024 |
| Border Energi Ltd | Professional & scientific | 2024 |
| Born in the Lakes Ltd | Wholesale & retail | 2024 |
| BOW Enterprises Limited | Other services | 2018 |
| Bowfell Consulting Limited | Professional & scientific | 2014 |
| Bowness Bay Brewing Limited | Manufacturing | 2011 |
| Bowness Bay Investments (Holdings) Limited | Financial services | 2016 |
| Bowness Bay Investments Limited | Real estate | 2016 |
| Box Tree Management Company Limited | Households | 2005 |
| Boyd CMC Limited | Construction | 2022 |
| BPR Limited | Construction | 2023 |
| Bracken Hill Farms Limited | Professional & scientific | 2009 |
| Brackens Roofing & Building Company Limited | Construction | 1997 |
| Brancaster Homecare Limited | Health & social care | 2008 |
| Brand Sales Solutions Limited | Professional & scientific | 2021 |
| Branda Official Ltd | Wholesale & retail | 2021 |
| Brandreth Foods Ltd | Manufacturing | 2020 |
| Brandwood Moor Limited | Agriculture & fishing | 2011 |
| BRC Linen & LET Management Ltd | Wholesale & retail | 2026 |
| BRF 26 Ltd | Professional & scientific | 2026 |
| Brian Capstick Welding Limited | Manufacturing | 2001 |
| Brian Edward Limited | Arts & recreation | 1999 |
| Brian Ramwell Classic Interiors Limited | Manufacturing | 2004 |
| Brice Music Ltd | Arts & recreation | 2021 |
| Brigantia Stone Services Limited | Wholesale & retail | 2024 |
| Brigg House Barn Management Company Limited | Real estate | 2022 |
| Bright and Shine BSK Ltd | Administrative & support | 2017 |
| Bright Red FOX Creative Ltd | Professional & scientific | 2024 |
| Brighter Futures Educational Limited | Real estate | 2017 |
| Britican Design & Build Ltd | Construction | 2002 |
| BRITTON2026 Ltd | Hospitality | 2026 |
| BRM Holding Co Limited | Financial services | 2026 |
| Broom Close Residents Association Limited | Households | 1997 |
| Broombys Ltd | Real estate | 2025 |
| Broughton & Beech Ltd | Health & social care | 2014 |
| Brown & Co (Kendal) Limited | Professional & scientific | 2011 |
| Brown and Rigg Trading Ltd | Wholesale & retail | 2024 |
| Browns IT Ltd | Information & communication | 2021 |
| Bryan Bland Joinery Limited | Construction | 2002 |
| BTN Electrical Contractors Limited | Construction | 2006 |
| Bubble and Squeak Dog Spa Limited | Agriculture & fishing | 2024 |
| Build Stroy Ltd | Construction | 2022 |
| Building Systems Services Ltd | Administrative & support | 2026 |
| Bumpsters Limited | Wholesale & retail | 2008 |
| Burga Properties Limited | Financial services | 2025 |
| Burlington Property Management Limited | Real estate | 2013 |
| Burnscunningham Ltd | Hospitality | 2017 |
| Burton Property Management Company Limited | Real estate | 2007 |
| Burton Villas Management Ltd | Households | 2013 |
| Busybase Limited | Professional & scientific | 1976 |
| Butcherco Ltd | Wholesale & retail | 2020 |
| Butterfield & Butterfield Ltd | Real estate | 2018 |
| Butterfield Business Services Ltd | Administrative & support | 2023 |
| Byroms Furnishings (Kendal) Limited | Extraterritorial | 2013 |
| C & E Nelson Limited | Manufacturing | 2021 |
| C J Askew Limited | Construction | 2011 |
| C J Miller Limited | Education | 2020 |
| C P Catering Equipment Ltd | Wholesale & retail | 2002 |
| C S Mortgage Solutions Limited | Extraterritorial | 2019 |
| C S Retirement Solutions Limited | Extraterritorial | 2019 |
| C S Wealth Solutions Limited | Financial services | 2019 |
| C W Alarms & Electrical Ltd | Construction | 2017 |