| Belheid Limited | Real estate | 2018 |
| Bells Boxing Limited | Arts & recreation | 2026 |
| BERGHOLT1884 Ltd | Professional & scientific | 2025 |
| Bernicia Limited | Real estate | 2001 |
| Best Nurseries Limited | Education | 2014 |
| Best Vision Ltd | Other services | 2021 |
| Besty's Barbers Ltd | Other services | 2023 |
| Bethan Kershaw Ltd | Professional & scientific | 2021 |
| BFS Property Limited | Real estate | 2022 |
| Bhojana Hedworth Curry House Limited | Hospitality | 2023 |
| BID Buddy UK Limited | Administrative & support | 2019 |
| Big Box Consultants Limited | Professional & scientific | 2014 |
| Big Box Management Services Limited | Real estate | 2018 |
| Big Local Jarrow CIC | Administrative & support | 2021 |
| Biscop House Management Company Limited | Extraterritorial | 2007 |
| Bishamon Coatings Ltd | Construction | 2020 |
| BJT Ltd | Other services | 2020 |
| Blacks Corner Tramways Company Ltd | Hospitality | 2022 |
| Blue Sky Design Management Ltd | Professional & scientific | 2023 |
| Bluejay Wellness CIC | Education | 2021 |
| BM Newco 1 2026 Limited | Financial services | 2026 |
| Boccprop Limited | Real estate | 2025 |
| Bodlewell House RTM Company Limited | Households | 2018 |
| Bold Recovery Limited | Health & social care | 2026 |
| Box Accounts Ltd | Professional & scientific | 2013 |
| Box Advisory Services Limited | Administrative & support | 2025 |
| Box Digital Limited | Professional & scientific | 2026 |
| Box Payroll Limited | Professional & scientific | 2025 |
| Box Property NE Limited | Households | 2025 |
| Boxbell Ltd | Construction | 2019 |
| Brawler Clothing Ltd | Wholesale & retail | 2020 |
| Brec (Holdings) Limited | Administrative & support | 2012 |
| Brec (NE) Limited | Manufacturing | 1999 |
| Bridlewhickham Ltd | Hospitality | 2025 |
| Brightlight Management Limited | Real estate | 2003 |
| Brill Driving School Ltd | Education | 2023 |
| Britaero Consulting Ltd | Professional & scientific | 2016 |
| BRL Civil Engineering Ltd | Construction | 2024 |
| Brooks Fire and Security Limited | Administrative & support | 2021 |
| Bros UN Ltd | Real estate | 2022 |
| Brzozowski Holdings Ltd | Financial services | 2025 |
| Bsbb 3 Ltd | Education | 2021 |
| BT Wind Repairs Ltd | Manufacturing | 2023 |
| Building & Facade Solutions Ltd | Wholesale & retail | 2021 |
| Buildout Property Ltd | Construction | 2025 |
| Burham Ltd | Construction | 2017 |
| Burnham Engineering and Controls Limited | Professional & scientific | 2011 |
| Butler Consulting Limited | Professional & scientific | 2023 |
| Butler Property Management Limited | Households | 2025 |
| Buyproducts Ltd | Administrative & support | 2018 |
| Byker Grave Ltd | Arts & recreation | 2023 |
| C Toby Property Limited | Real estate | 2024 |
| Ca&A Homes Limited | Construction | 2024 |
| Cadsolve UK Ltd | Professional & scientific | 2016 |
| Cadxtec Limited | Professional & scientific | 2025 |
| Cala Sales Ltd | Wholesale & retail | 2023 |
| Caldwell Enterprise Limited | Wholesale & retail | 2022 |
| Callforstaff Recruitment Limited | Administrative & support | 2025 |
| Cameo Digital Limited | Administrative & support | 2016 |
| Campbell & Winstanley Partnership Ltd | Real estate | 2007 |
| Canny Wild CIC | Professional & scientific | 2023 |
| Carlton House Properties Limited | Real estate | 2016 |
| Carmichael Nuclear Ltd | Construction | 2019 |
| Carnson Properties Ltd | Real estate | 2024 |
| Carpet and Flooring Warehouse NE Limited | Wholesale & retail | 2024 |
| Carr's Drylining Services Ltd | Construction | 2026 |
| Carter's Convenience Stores Ltd | Wholesale & retail | 2011 |
| Casablanca Publications Limited | Arts & recreation | 2006 |
| CDC Plumbing & Heating Limited | Construction | 2012 |
| CF Electrical (North East) Ltd | Construction | 2021 |
| Chaffinch Windows and Doors Ltd | Construction | 2025 |
| Chelest Cater Limited | Hospitality | 2024 |
| Chelest Leisure Limited | Hospitality | 2021 |
| Chemcare Holdings Ltd | Wholesale & retail | 2020 |
| Chemcare Limited | Wholesale & retail | 2004 |
| Chesterfields of London Limited | Wholesale & retail | 2012 |
| Chris Sykes 511 Limited | Professional & scientific | 2024 |
| CI Wind Limited | Professional & scientific | 2025 |
| City Couriers Group Ltd | Transport & logistics | 2025 |
| CJ Taverns Limited | Administrative & support | 2013 |
| Cjconnolly Services Ltd | Construction | 2025 |
| CK Welding Services Ltd | Manufacturing | 2025 |
| Classic Occasions Limited | Administrative & support | 2024 |
| CLC Investments Limited | Financial services | 2021 |
| Cleaning CK Ltd | Administrative & support | 2020 |
| Cleaning GEM Ltd | Administrative & support | 2025 |
| Clear BID Ltd | Professional & scientific | 2016 |
| Clear Choice Roofing &Upvc Maintenance Limited | Construction | 2025 |
| Cliff & Sons Ltd | Real estate | 2026 |
| CMC Insights Ltd | Information & communication | 2024 |
| Codfella Food Hub Ltd | Hospitality | 2026 |
| Combined Touch Community Interest Company | Other services | 2015 |
| Commissioners Wharf Management Company Limited | Households | 2003 |
| Community Corner Community Interest Company | Wholesale & retail | 2016 |
| Compreserve Ltd | Professional & scientific | 2025 |
| Concam Interiors Ltd | Construction | 2020 |
| Consultingbros Limited | Information & communication | 2024 |
| Contentandco Ltd | Professional & scientific | 2026 |
| Conwaytech Solutions Ltd | Information & communication | 2024 |
| Cooks Hydraulics Ltd | Professional & scientific | 2024 |