| Bold Earth Limited | Administrative & support | 2011 |
| Bollands Investco Limited | Real estate | 2019 |
| Bolton Premier Limited | Wholesale & retail | 2024 |
| Bombshell Design Ltd | Professional & scientific | 2021 |
| Bonasystems Europe Ltd | Manufacturing | 2008 |
| Boolinor Ltd | Information & communication | 2026 |
| Booth Inspection Limited | Professional & scientific | 2012 |
| Botak Medcare Ltd | Health & social care | 2025 |
| Bourne END Lettings LLP | | 2018 |
| Bowen Family Holdings Ltd | Real estate | 2019 |
| Bowen Family Partnership LLP | | 2019 |
| Brabant Productions Limited | Information & communication | 2018 |
| Brabiner Services Ltd | Professional & scientific | 2008 |
| Bradley Psychological Service Ltd | Health & social care | 2017 |
| Branch Property Holdings Ltd | Real estate | 2019 |
| Branch Property Partnership LLP | | 2019 |
| Brans Services Ltd | Professional & scientific | 2022 |
| BRD Northern Ltd | Professional & scientific | 2026 |
| Brett Property Assets LLP | | 2023 |
| BRG Family Partnership LLP | | 2018 |
| BRG Property Limited | Real estate | 2015 |
| Bridge Building Solutions Limited | Construction | 2024 |
| Bridge House Developments (NE) Limited | Construction | 2024 |
| Bridlington DP Ltd | Wholesale & retail | 2016 |
| Bright Hill Ltd | Construction | 2021 |
| Bright Hill NO 1 Ltd | Construction | 2021 |
| Bright Hill Properties Ltd | Real estate | 2018 |
| Bright Hill Properties Partnership LLP | | 2019 |
| Bright Star Property Partnership LLP | | 2017 |
| Bristol Housing & Support Ltd | Hospitality | 2007 |
| Briteprint Signs & Engraving Ltd | Manufacturing | 2012 |
| Britton Homes LLP | | 2020 |
| Brogan Family Partnership LLP | | 2018 |
| Brompton Homes (North East) Ltd | Real estate | 2015 |
| Brookfield and Bunting (Management) Limited | Households | 1975 |
| Brooklyn Property Limited | Real estate | 2018 |
| Brow Junction Ltd | Other services | 2021 |
| Browns Project Consulting Limited | Construction | 2023 |
| Bsjj Limited | Professional & scientific | 2022 |
| BT Inspection Ltd | Professional & scientific | 2024 |
| Btem Limited | Professional & scientific | 2021 |
| Buddys Cafe Limited | Hospitality | 2024 |
| Budget Roofing & Plastic’S Ltd | Construction | 2025 |
| Burn Road Investments Ltd | Construction | 2018 |
| Busy Woman Ltd | Arts & recreation | 2025 |
| Byte Digital Ltd | Information & communication | 2012 |
| BZH Ltd | Health & social care | 2023 |
| C & J Strong WP Ltd | Administrative & support | 2024 |
| C & R Utilities Ltd | Energy | 2010 |
| C & T Utilities Limited | Construction | 2019 |
| C a Smith & J M Hancock Properties Limited | Real estate | 2019 |
| C Bovill WP Ltd | Administrative & support | 2024 |
| C J Motor Solutions Ltd | Financial services | 2025 |
| C M C Supplies Limited | Wholesale & retail | 2002 |
| C P Estates Limited | Real estate | 2000 |
| C P Performance Limited | Wholesale & retail | 2021 |
| C.Us Operations Ltd | Wholesale & retail | 2022 |
| Cabin Folk Ltd | Professional & scientific | 2022 |
| Cable Properties and Investments Limited | Real estate | 2005 |
| Cablenova Ltd | Wholesale & retail | 2023 |
| CAFE18 Ltd | Hospitality | 2025 |
| CAG Family Partnership LLP | | 2021 |
| Cain Property Investments Ltd | Real estate | 2021 |
| Cake IT Ltd | Wholesale & retail | 2022 |
| Cakes Bakes & Shakes Desserts Billingham Ltd | Wholesale & retail | 2025 |
| Calcad Ltd | Professional & scientific | 2014 |
| Calm Within Community Interest Company | Health & social care | 2023 |
| Cambrian Escape (2025) Limited | Hospitality | 2025 |
| Cameron Hall Commercial Ltd | Construction | 2022 |
| Cameron Hall Developments Limited | Construction | 1976 |
| Cameron Hall Holdings Limited | Extraterritorial | 2020 |
| Cameron Hall Homes Limited | Construction | 2015 |
| Campbell & Hall Engineering Limited | Manufacturing | 2002 |
| Cant Group Ltd | Wholesale & retail | 2025 |
| Canter Property Investments Ltd | Real estate | 2021 |
| Canter Property Partnership LLP | | 2021 |
| Canweb Ltd | Real estate | 2019 |
| Car Glass North East Ltd | Wholesale & retail | 2004 |
| Car Technics (NE) Ltd | Wholesale & retail | 2023 |
| Carasmile Dent Ltd | Wholesale & retail | 2023 |
| Carbonetrix Limited | Professional & scientific | 2024 |
| Carerx Limited | Wholesale & retail | 2023 |
| Cargo Tech Limited | Transport & logistics | 2017 |
| Carpenter Partnership LLP | | 2023 |
| Carpet Land Contracts Ltd | Wholesale & retail | 2011 |
| Carro Consortium Ltd | Professional & scientific | 2024 |
| Carro of Wynyard Ltd | Professional & scientific | 2013 |
| Carryvibe Ltd | Wholesale & retail | 2026 |
| Carson Family Holdings Ltd | Real estate | 2017 |
| Carson Family Partnership LLP | | 2017 |
| Cartwright IT Consultants Ltd | Information & communication | 2019 |
| Castle Construction North West Limited | Construction | 2018 |
| Castle Eden Studios Ltd | Real estate | 2011 |
| Caswells Vending Limited | Hospitality | 2017 |
| Catalytic Technologies Ltd | Administrative & support | 2010 |
| Cavendish (Northern) Limited | Manufacturing | 1982 |
| Cavendish (Northern) Property Developments Limited | Real estate | 2002 |
| Cavtrack Limited | Information & communication | 2025 |
| CCT Demolition Limited | Administrative & support | 2019 |
| CD Electrical & Mechanical Ltd | Construction | 2023 |