| Brucciani (Carlisle) Limited | Wholesale & retail | 2004 |
| Bruce Murray Land Agency Limited | Professional & scientific | 2023 |
| Bruno Monteiro Limited | Transport & logistics | 2014 |
| Bryan Morley Electrical Limited | Construction | 2003 |
| Bryngwyn Limited | Agriculture & fishing | 2018 |
| Bryson JOB Evaluation Ltd | Administrative & support | 2025 |
| Bsblh Limited | Hospitality | 2025 |
| Bseenbsafe Limited | Wholesale & retail | 2009 |
| BSP Accountancy Services Ltd | Professional & scientific | 2018 |
| Bspoqe (Carlisle) Ltd | Wholesale & retail | 2020 |
| Bspoqe Group Limited | Wholesale & retail | 2020 |
| BT & S Investments Ltd | Hospitality | 2025 |
| BTI Netplus Ltd | Information & communication | 2009 |
| Buckleberry Hotels Ltd | Hospitality | 2014 |
| Budden Group Ltd | Real estate | 2025 |
| Budget Blinds Carlisle Limited | Wholesale & retail | 2015 |
| Budget Buy Tyres Ltd T/As Tyres R US Carlisle Ltd | Wholesale & retail | 2011 |
| Budget Exhaust and Tyre Centre Limited | Wholesale & retail | 2025 |
| Build RS (Cumbria) Limited | Construction | 2026 |
| Building Belle Ltd | Real estate | 2023 |
| Building TEC Limited | Construction | 2001 |
| Buildings 4 U Limited | Wholesale & retail | 2023 |
| Builditwithus Limited | Construction | 2025 |
| Buildupwithus Limited | Construction | 2025 |
| Bull Propco Ltd | Real estate | 2025 |
| Bullamore Systems Limited | Health & social care | 2015 |
| Bulman Building Ltd | Construction | 2025 |
| Bulman Farming Company | Agriculture & fishing | 2021 |
| Bump N Scuff Repairs Limited | Wholesale & retail | 2002 |
| Burbain Property Group Ltd | Real estate | 2025 |
| Burcher Jennings Pricing Consultants Limited | Professional & scientific | 2021 |
| Burge Halston Limited | Construction | 2011 |
| Burnett & Black Limited | Real estate | 2014 |
| Burnett House Management Company Limited | Real estate | 2000 |
| Burnetts Limited | Professional & scientific | 2002 |
| Burnetts Solicitors LLP | | 2019 |
| Burnetts Trust Corporation Limited | Financial services | 2022 |
| Burrows Industrial Roofing Limited | Construction | 1999 |
| Bushido Support Services Community Interest Company | Information & communication | 2014 |
| Business 2 Door Ltd | Professional & scientific | 2018 |
| Business Accelerator (UK) Limited | Professional & scientific | 2008 |
| Business Operational Services Limited | Transport & logistics | 1996 |
| Busy BEE NW Ltd | Administrative & support | 2018 |
| Butler Accountancy Services Limited | Professional & scientific | 2001 |
| Butterfield Close (Brigham) Limited | Households | 2016 |
| Butterfly (Finance) Limited | Financial services | 2017 |
| Butterfly Group Healthcare Limited | Health & social care | 2014 |
| Butterworth Property Services Limited | Extraterritorial | 2014 |
| BY Molly&Izzie Ltd | Wholesale & retail | 2018 |
| Byers Brothers Cumbria Limited | Manufacturing | 1980 |
| Byers Brothers Limited | Manufacturing | 2021 |
| Byfleet Village Football Club Ltd | Arts & recreation | 2025 |
| C & a Graham Farm Limited | Agriculture & fishing | 2024 |
| C & D Debt Recovery Limited | Administrative & support | 2024 |
| C & D Joinery Limited | Construction | 2020 |
| C & J Flooring Ltd | Construction | 2024 |
| C & K Herd Consultancy Ltd | Financial services | 2025 |
| C & M Motors (Cumbria) Ltd | Wholesale & retail | 2023 |
| C & V Dixon | Financial services | 2019 |
| C Carruthers & SON Ltd | Construction | 2010 |
| C Davidson Contractors Limited | Other services | 2020 |
| C F Services (U.K.) Limited | Construction | 2013 |
| C J City Properties Limited | Real estate | 2004 |
| C J Mair Consulting Limited | Administrative & support | 2017 |
| C J Stalker Limited | Transport & logistics | 2014 |
| C K Steelwork & Cladding Limited | Construction | 2021 |
| C Nichol (Construction) Ltd | Construction | 2020 |
| C Nicholson Cumbria Ltd | Transport & logistics | 2022 |
| C P Knight Holdings Ltd | Construction | 2018 |
| C R Kendall Groundworks Ltd | Construction | 2021 |
| C Watt Consultancy Limited | Professional & scientific | 2020 |
| C Wright Holdings Ltd | Financial services | 2024 |
| C&D Auction Marts Limited | Administrative & support | 2015 |
| C&D Express Logistics Company Ltd | Transport & logistics | 2025 |
| C&D Rural Ltd | Real estate | 2023 |
| C&T London Ltd | Administrative & support | 2017 |
| C. D. Atack Ltd | Hospitality | 2022 |
| C.A.E.S. Holdings Limited | Manufacturing | 2016 |
| C.A.E.S. Limited | Manufacturing | 1972 |
| C.Docherty Logistics Ltd | Transport & logistics | 2025 |
| C.E.G.H.J.N. (UK) Limited | Arts & recreation | 2019 |
| C.P.M. (15-20) Limited | Real estate | 2015 |
| C.U.F.C. Holdings Limited | Extraterritorial | 1992 |
| CA Story Limited | Construction | 2014 |
| CA Tanning and Recovery Ltd | Other services | 2025 |
| CA Travel Cumbria Limited | Transport & logistics | 2026 |
| CA Wheels Limited | Wholesale & retail | 2021 |
| Ca-Events Limited | Administrative & support | 2009 |
| CA1 Sport Limited | Wholesale & retail | 2006 |
| CA2 Barbers Ltd | Other services | 2023 |
| CA2 Cumbria Store Limited | Wholesale & retail | 2026 |
| CA2 Denton Vapespot Limited | Wholesale & retail | 2026 |
| CA4 Properties Ltd | Real estate | 2025 |
| CA5 Estates Ltd | Real estate | 2025 |
| Cabbage & Curtainrail (Cumbria) Limited | Wholesale & retail | 2018 |
| CACHE4 IT Solutions Limited | Information & communication | 2015 |
| Caddy's Fish & Chips Ltd | Hospitality | 2023 |
| Cafe Central Carlisle Ltd | Hospitality | 2018 |
| Cairn Beck Management Limited | Real estate | 2018 |
| Cairn Mill RTM Company Limited | Real estate | 2011 |