| Brandon TBJ Ltd | Transport & logistics | 2025 |
| Brickwork Direct Limited | Construction | 2003 |
| Bright Path Physiotherapy Ltd | Other services | 2025 |
| Brightercartoon Limited | Information & communication | 2012 |
| Brit Bath Ltd | Construction | 2024 |
| Broadside Marketing Limited | Extraterritorial | 2017 |
| Broadway Engineering Services NE Limited | Administrative & support | 2021 |
| Brohann Construction Ltd | Construction | 2011 |
| Bromarsh Court Limited | Real estate | 2005 |
| Brother's Fresh Ltd | Wholesale & retail | 2024 |
| Brow WOW UK Ltd | Other services | 2023 |
| Brown Vehicle Repairs Limited | Wholesale & retail | 2021 |
| Brownlow 64 Limited | Extraterritorial | 2014 |
| Browns Childcare Ltd | Education | 2026 |
| Browns Cyber Solutions Ltd | Information & communication | 2026 |
| Browns Estate Sales Limited | Real estate | 2026 |
| Browns Letting Agents Limited | Real estate | 2026 |
| Browns Plumbing & Heating Services Ltd | Construction | 2026 |
| Browns Properties (NE) Limited | Households | 2019 |
| Browns Sales Limited | Real estate | 2021 |
| Bryanwood Ltd | Construction | 2024 |
| BT Cleaning NE Ltd | Administrative & support | 2025 |
| Buddy and Friends Ltd | Other services | 2025 |
| Buddy's Pet Supplies Limited | Wholesale & retail | 2025 |
| Budget Buses Limited | Transport & logistics | 2017 |
| Bullseye Darts Academy Limited | Education | 2025 |
| Bullseye Leisure Sports Limited | Wholesale & retail | 2024 |
| Bunker Financial Services Ltd | Financial services | 2026 |
| Burge Surtees Associates Limited | Information & communication | 2005 |
| Burger Bar South Shields Ltd | Hospitality | 2024 |
| Burn Commissioning Services Limited | Professional & scientific | 2024 |
| Burnsmith Limited | Professional & scientific | 1871 |
| BUS & Truck Training Ltd | Education | 2026 |
| BW Echo Ltd | Health & social care | 2025 |
| BW FM Services Limited | Construction | 2025 |
| BW Mech Services Ltd | Manufacturing | 2022 |
| BW Virtual Ltd | Wholesale & retail | 2023 |
| BWD Maintenance Limited | Construction | 2019 |
| C & B Electrical Limited | Construction | 2008 |
| C & K Little Threads Ltd | Wholesale & retail | 2026 |
| C D S Kitchens Ltd | Construction | 2019 |
| C G Brennan Limited | Construction | 2022 |
| C H Guitars Limited | Arts & recreation | 2013 |
| C Hilton Offshore Services Ltd | Construction | 2026 |
| C J Todd Education Management Ltd | Professional & scientific | 2015 |
| C J Y Telecoms Ltd | Construction | 2019 |
| C M Young FIC Limited | Financial services | 2024 |
| C M Young Holdings Limited | Financial services | 2024 |
| C Mason Ltd | Hospitality | 2026 |
| C Vaughan Locums Ltd | Professional & scientific | 2020 |
| C W Charlton Ltd | Real estate | 2023 |
| C Williams Refurbs Ltd | Construction | 2025 |
| C&M Contracting Ltd | Construction | 2015 |
| C&T Outfitting Ltd | Construction | 2017 |
| C.C. Property Management Limited | Real estate | 2006 |
| C.U. Inspection Services PTE Ltd | Administrative & support | 2022 |
| Cabesco's Ltd | Hospitality | 2025 |
| Cafe Aneesas Ltd | Hospitality | 2026 |
| Cafe at the Corner Ltd | Hospitality | 2018 |
| Cafe at the House Limited | Hospitality | 2015 |
| Cafe Boldon Limited | Hospitality | 2021 |
| Cafe India North Ltd | Hospitality | 2023 |
| Caffe MIO Limited | Hospitality | 2012 |
| Café 42 Ltd | Hospitality | 2018 |
| CAL507 Coaching Ltd | Health & social care | 2026 |
| Cala Transport Limited | Transport & logistics | 2025 |
| Call 2 Clean Ltd | Administrative & support | 2021 |
| Call on Kevin Ltd | Transport & logistics | 2021 |
| Cambridge Court (Bishop Auckland) Management Company Limited | Real estate | 2011 |
| Camden Clinic Ltd | Other services | 2024 |
| Camden Clinicians Ltd | Health & social care | 2025 |
| Campbell Homes (NE) Limited | Real estate | 2018 |
| Campbell Wedding Cars Ltd | Other services | 2009 |
| Campbell's Fruit & VEG Limited | Wholesale & retail | 2015 |
| Cancer Connections Limited | Health & social care | 2006 |
| Cando Design Limited | Professional & scientific | 2017 |
| Canterbury Way (Fellgate) Management Company Limited | Households | 1998 |
| Capital Halal Meat & Grocery South Shields Ltd | Wholesale & retail | 2024 |
| Capricorn One Ltd | Extraterritorial | 2020 |
| Car Electrical (UK) Limited | Wholesale & retail | 2010 |
| Car Parts Express (NE) Limited | Wholesale & retail | 2015 |
| Caraway Holdings Ltd | Administrative & support | 2024 |
| Carcannon UK Ltd | Administrative & support | 2009 |
| Careplay Solutions Ltd | Wholesale & retail | 2026 |
| Cargotech Installations Ltd | Manufacturing | 2025 |
| Carl's Carvery's Limited | Hospitality | 2015 |
| Carrsevco Ltd | Other services | 2016 |
| Carruthers and Sons,Limited | | 1947 |
| Cartemy Ltd | Information & communication | 2026 |
| CAS Hire Ltd | Administrative & support | 2020 |
| Cask Lounge Limited | Hospitality | 2019 |
| Cask Properties Ltd | Real estate | 2022 |
| Cast TEC Limited | Wholesale & retail | 2002 |
| Castle Hill Expert Witness Services by Julia Parvia Ltd | Health & social care | 2026 |
| Castle Tees Ltd | Manufacturing | 2023 |
| Catalage Limited | Professional & scientific | 2014 |
| Catalin Iordan Logistics Limited | Transport & logistics | 2025 |
| Caterminch Limited | Financial services | 2019 |
| CB Fitness Limited | Arts & recreation | 2022 |
| CB MAX Ltd | Construction | 2025 |