| Avenue Management Company (Leigh) Limited | Real estate | 2007 |
| Avista Care Limited | Health & social care | 2014 |
| Avista Lakeland Properties Limited | Real estate | 2023 |
| Awaken Business Sustainability Ltd | Administrative & support | 2025 |
| Ayesha Brow & Beauty Ltd | Other services | 2025 |
| B & H Motors Limited | Wholesale & retail | 2002 |
| B W Scott Limited | Wholesale & retail | 2003 |
| B&K Mayson Contracting Services Ltd | Construction | 2019 |
| B. Rourke Plasterer Ltd | Construction | 2002 |
| B.T. and J. Developments Limited | Real estate | 2007 |
| BA & LW Properties Ltd | Real estate | 2022 |
| Barr & Sons Limited | Real estate | 2020 |
| Barrnon Defence Limited | Professional & scientific | 2020 |
| Barrnon Media Limited | Information & communication | 2020 |
| Barry Scott Limited | Construction | 2016 |
| Barston Enterprises Limited | Professional & scientific | 2015 |
| Basicly Ltd | Information & communication | 2025 |
| Beauty in the Barn Limited | Other services | 2018 |
| Beckermet Estates Limited | Real estate | 1996 |
| Beckstone Law Limited | Professional & scientific | 2017 |
| Beckstone Properties Limited | Real estate | 2021 |
| Beehive Limited(The) | Real estate | 1910 |
| Behzad Barbers Ltd | Other services | 2025 |
| Beleclare Ltd | Health & social care | 2022 |
| Belvedere Dental Practice Company Limited | Health & social care | 2010 |
| Bennetts LPM Limited | Administrative & support | 2015 |
| Berkshire Competitions Ltd | Other services | 2023 |
| Best Kebab Workington Ltd | Hospitality | 2016 |
| Bethany House Limited | Health & social care | 2002 |
| Bethany Sullivan Hair Ltd | Other services | 2025 |
| Bethany's Hair and Beauty Limited | Other services | 2018 |
| Bethshan Nursing Home Limited | Health & social care | 2009 |
| Better Tomorrow Brands Ltd | Manufacturing | 2023 |
| Bewley Motorsport Limited | Arts & recreation | 2023 |
| BHS Construction Services Limited | Construction | 2008 |
| BIA Engineering Ltd | Administrative & support | 2015 |
| BID Writters Limited | Administrative & support | 2022 |
| BIN Blaster Cumbria Ltd | Administrative & support | 2025 |
| Bismillah Balti Limited | Hospitality | 2015 |
| Bitedelight Limited | Hospitality | 2023 |
| Blinco Engineering Limited | Other services | 2013 |
| Blue Switch Marketing Ltd | Information & communication | 2014 |
| Blue Tokay Limited | Arts & recreation | 2010 |
| Bluemotion-E Limited | Wholesale & retail | 2025 |
| BM 2026 Ltd | Education | 2026 |
| Bodyflex 2025 Ltd | Arts & recreation | 2025 |
| Bodywork Biomechanics & Massage Ltd | Health & social care | 2019 |
| Boilertech - North West Ltd | Construction | 2024 |
| Bonny Meadows Management Company Limited | Households | 2023 |
| Bonscombe Management Services Limited | Professional & scientific | 2026 |
| Book Developments Limited | Extraterritorial | 2014 |
| Boomer Tech UK Ltd | Information & communication | 2025 |
| Bowers Garage Ltd | Wholesale & retail | 2000 |
| Boxer Security Ltd | Administrative & support | 2025 |
| Braniff & Davidson Opticians Limited | Health & social care | 2001 |
| Branthwaite Hall Agricultural Limited | Real estate | 1996 |
| Branthwaite Hall Developments Limited | Other services | 2002 |
| Brassac Ltd | Administrative & support | 2020 |
| Breylorann Limited | Professional & scientific | 2014 |
| Brian Fulton Limited | Manufacturing | 2001 |
| Brian Morris Logistics Ltd | Transport & logistics | 2026 |
| Brickolini Ltd | Real estate | 2021 |
| Bricks & Mortar (Cumbria) Limited | Real estate | 2008 |
| Bridge END Solutions Limited | Professional & scientific | 2009 |
| Bridge the GAP Sales Ltd | Education | 2026 |
| Brightside Events Limited | Hospitality | 2024 |
| Brigrove (Five) Limited | Real estate | 2003 |
| Brigrove (SIX) Limited | Real estate | 2006 |
| Brigrove Limited | Real estate | 2001 |
| Britton-Hillary Ltd | Other services | 2011 |
| Buchanan Property Developments (Cumbria) Limited | Real estate | 2024 |
| Buckley Trading Ltd | Agriculture & fishing | 2018 |
| Bulldog Drainage Ltd | Other services | 2017 |
| Burney & Sons Property Ltd | Real estate | 2025 |
| Buy Land Plant Trees CIC | Agriculture & fishing | 2020 |
| C & E Builders Limited | Construction | 2003 |
| C & GS Property Limited | Real estate | 2022 |
| C & T Quality Homes Limited | Construction | 2003 |
| C D Restorations Limited | Wholesale & retail | 2023 |
| C G Property Investments (Cumbria) Limited | Hospitality | 2020 |
| C H Steel Fabrication Limited | Manufacturing | 2003 |
| C Hodgson Roofing Limited | Construction | 2021 |
| C Horsley Limited | Agriculture & fishing | 2009 |
| C M Driving Services (Cumbria) Ltd | Transport & logistics | 2019 |
| C Tubman Consulting Limited | Professional & scientific | 2024 |
| C&R Property Connect Ltd | Real estate | 2025 |
| Caffreys Training Centre Ltd | Education | 2023 |
| Caine Consulting Engineers Ltd | Professional & scientific | 2007 |
| Cambridge Open College Ltd | Education | 2015 |
| Camille Cape Wellbeing Limited | Health & social care | 2025 |
| Campbell-Gray Limited | Professional & scientific | 2016 |
| Candlestick Properties Ltd | Real estate | 2025 |
| Candy Cabs Cumbria Limited | Manufacturing | 2023 |
| Capricorn Garden Services Limited | Administrative & support | 2015 |
| Car Vault Lillyhall Ltd | Wholesale & retail | 2025 |
| Carnegie Workington Ltd | Hospitality | 2014 |
| Carrold Hill Ltd | Financial services | 2022 |
| Cartridge 2 Print Limited | Wholesale & retail | 2014 |
| CAS Inspections Limited | Professional & scientific | 2023 |
| Caspian Cumberia Limited | Hospitality | 2025 |