| 04986380 Limited | Arts & recreation | 2003 |
| 3L&L Limited | Real estate | 2023 |
| 9 Food and Wine Ltd | Wholesale & retail | 2025 |
| A and a Hire Limited | Transport & logistics | 2024 |
| A G S Communications & Services Ltd | Information & communication | 2018 |
| A H Signalling Design Limited | Transport & logistics | 2013 |
| A Turnbull Static Caravan Sales North East Ltd | Hospitality | 2023 |
| A1 Chop Suey Ltd | Hospitality | 2025 |
| A1 Event Hire Ltd | Administrative & support | 2022 |
| A19 Erecting & Site Services Ltd | Administrative & support | 2024 |
| Aall Electrical Services Ltd | Construction | 2019 |
| Aaron Contract Electrical Ltd. | Construction | 2015 |
| Abham Solutions Limited | Transport & logistics | 2016 |
| Ace Electrical Group Ltd | Construction | 2026 |
| AG Watson & Sons Limited | Agriculture & fishing | 2011 |
| AG1.SERV Limited | Extraterritorial | 2026 |
| AIO Business Center Limited | Real estate | 2024 |
| Aiobc Limited | Real estate | 2024 |
| AJ Aluminium Ltd | Manufacturing | 2021 |
| AKM Wind Services Ltd | Construction | 2026 |
| ALL in One Business Centre Limited | Real estate | 2024 |
| ALL Saints Community Centre Ltd | Hospitality | 2023 |
| Alma Care With Passion Ltd | Health & social care | 2024 |
| Alpha Carpentry & Conversions Ltd | Manufacturing | 2020 |
| Altiora Legal Ltd | Administrative & support | 2026 |
| AMC Automation Limited | Professional & scientific | 2021 |
| Amrp Buy to LET Advisory Services Limited | Real estate | 2013 |
| Amrp Holiday Lets Ltd | Hospitality | 2023 |
| Andrew Marshall Residential Properties Ltd | Households | 2006 |
| Andypol Transport Ltd | Transport & logistics | 2021 |
| Anehta Engineering Ltd | Professional & scientific | 2024 |
| Apeiron Endurance Limited | Health & social care | 2024 |
| Apex Security Management Ltd | Administrative & support | 2023 |
| Appletree Building Contractors Ltd | Construction | 2016 |
| Approach TOO CIC | Education | 2015 |
| AR Curam Limited | Construction | 2016 |
| AS Manufacturing Limited | Manufacturing | 2025 |
| Asset Risk Consult Ltd | Professional & scientific | 2020 |
| Autospec Motors Ltd | Transport & logistics | 2016 |
| Azura Property Investments Ltd | Real estate | 2020 |
| B & L Design and Build Ltd | Professional & scientific | 2019 |
| B H Renewables (NE) Ltd | Professional & scientific | 2024 |
| B&L Gray Pubs Ltd | Hospitality | 2026 |
| Bayhaven Limited | Construction | 2000 |
| Bayleaf Ferry Hill Ltd | Hospitality | 2022 |
| Bayleaf Main Street Ltd | Hospitality | 2025 |
| BBM Safety Training Ltd | Education | 2021 |
| Beldon Leisure Limited | Hospitality | 2022 |
| Belle Montagne Ltd | Wholesale & retail | 2018 |
| Bespoke Services (NE) Ltd | Transport & logistics | 2022 |
| Better Roads Limited | Construction | 2025 |
| Bettyswolloks Limited | Wholesale & retail | 2025 |
| Billy LAU Limited | Wholesale & retail | 2006 |
| Bishop Middleham Barn Co Limited | Households | 2019 |
| Blacks Properties Ltd | Real estate | 2021 |
| Blamire Printers Limited | Manufacturing | 1986 |
| Blue Falcon - Mark Robb Ltd | Agriculture & fishing | 2010 |
| Bluesky Business Services Limited | Extraterritorial | 2026 |
| Border Autos Ltd | Wholesale & retail | 2020 |
| Bovicil Ltd | Real estate | 2017 |
| Bowling Home Improvements Ltd | Construction | 2019 |
| Bright Futures Ferryhill CIC | Hospitality | 2023 |
| Brightsigns Agency Ltd | Other services | 2017 |
| Brodi's Pipework Services Ltd | Construction | 2024 |
| Broom Chippy Ltd | Hospitality | 2026 |
| Building and Joinery Services Ltd | Construction | 2026 |
| Buildpro Solution Service Ltd | Construction | 2024 |
| Burnside Logistics North East Ltd | Transport & logistics | 2025 |
| C B Z Utilities Ltd | Construction | 2008 |
| C Beattie and SON Limited | Agriculture & fishing | 2012 |
| C D I Innovative Construction Materials Limited | Wholesale & retail | 2012 |
| Cach Limited | Other services | 2010 |
| Cappuccilabs Ltd | Wholesale & retail | 2026 |
| Carla Trading Ltd | Information & communication | 2025 |
| Casg Group UK Ltd | Wholesale & retail | 2020 |
| Catertech (North East) Limited | Manufacturing | 2008 |
| CBS Media Ltd | Information & communication | 2025 |
| Cctdd Enterprise Ltd | Information & communication | 2025 |
| CD Electrical Mechanical Maintenance Ltd | Transport & logistics | 2019 |
| Centurion Waste Limited | Transport & logistics | 2017 |
| Cesar Logistic Ltd | Transport & logistics | 2014 |
| CGS Properties (NE) Ltd | Real estate | 2024 |
| Chalevee Cleaning Limited | Administrative & support | 2025 |
| Chameleon Spray Systems UK Ltd | Construction | 2021 |
| Charlie Davies Logistics Limited | Transport & logistics | 2025 |
| Cheezy Pizza Ltd | Hospitality | 2025 |
| Chelii Limited | Hospitality | 2025 |
| Chen Smiles Ltd | Health & social care | 2026 |
| Chilton Green Energy Foundation C.I.C. | Administrative & support | 2016 |
| Chilton Pizza Ltd | Hospitality | 2022 |
| Choose Happy Healing Ltd | Extraterritorial | 2021 |
| Chris Boyle Limited | Transport & logistics | 2022 |
| Christina Jewelry and Watches UK Ltd | Wholesale & retail | 2019 |
| CJ Halliday Logistics Ltd | Transport & logistics | 2025 |
| Claws 2 Paws Limited | Professional & scientific | 2014 |
| Cleveland Monumentals Limited | Wholesale & retail | 2013 |
| Coal Contractors Limited | Mining & quarrying | 1951 |
| Coats Properties Ltd | Real estate | 2023 |
| Colin Robinson Limited | Administrative & support | 2010 |
| Colosseum Construction Ltd | Construction | 2016 |