| Craze Central Limited | Professional & scientific | 2024 |
| Crazy COW Leisure Limited | Hospitality | 2024 |
| Creative Thinking Finance Limited | Professional & scientific | 2023 |
| CRH65 Limited | Professional & scientific | 2015 |
| Criminal Records Services Ltd | Administrative & support | 2006 |
| CRM Logistics Ltd | Transport & logistics | 2018 |
| Crmm Logistics Ltd | Transport & logistics | 2021 |
| Crossco (708) Limited | Construction | 2002 |
| Crossgate Estates Ltd | Real estate | 2003 |
| Crosskey Harrison Limited | Transport & logistics | 2018 |
| Crowley Independent Mortgage Advisors Ltd | Financial services | 2017 |
| Crownjp Ltd | Hospitality | 2025 |
| CRS Home Improvements Ltd | Construction | 2013 |
| CSD Media Limited | Information & communication | 2017 |
| CSN Ferryhill Limited | Arts & recreation | 2025 |
| CSN Holding Ltd | Financial services | 2019 |
| CSW Heating and Plumbing Limited | Construction | 2025 |
| CSW Homes (NE) Limited | Real estate | 2026 |
| CSW Pipeworks Ltd. | Manufacturing | 2017 |
| Cullercoats Property Management Limited | Real estate | 2012 |
| Curry Residential Ltd | Real estate | 2017 |
| Custom Fit Campers Ltd | Manufacturing | 2023 |
| Cutting Edge Recruitment Limited | Administrative & support | 2015 |
| Cw-Bms-Solutions Ltd | Manufacturing | 2018 |
| D & C Plumbing & Heating Limited | Construction | 2004 |
| D International Ltd | Professional & scientific | 2019 |
| D J Management Services Limited | Real estate | 2015 |
| D Pickering Ltd | Wholesale & retail | 2019 |
| D&J North East Limited | Financial services | 2024 |
| DA Property NE Ltd | Real estate | 2026 |
| Daja North East Ltd | Construction | 2024 |
| DAL Design and Build Ltd | Construction | 2025 |
| Dalkinsbakes Ltd | Wholesale & retail | 2025 |
| Dalziel and Ramshaw Group Limited | Real estate | 2026 |
| Dalziel Ventures Ltd | Real estate | 2022 |
| Dampline Ltd | Construction | 2025 |
| Danco Properties Limited | Real estate | 2006 |
| Dandlengraving Limited | Manufacturing | 2025 |
| Danelaw Developments Ltd | Real estate | 2017 |
| Dapa Delta Ltd | Professional & scientific | 2022 |
| Darren Bowman Property Services Ltd | Construction | 2024 |
| Dave Pickup Consulting Limited | Real estate | 2014 |
| Dave Warner Tiling Ltd | Construction | 2012 |
| David Griffiths Painter & Decorator Ltd | Construction | 2021 |
| David S Poole Accountancy Services Limited | Professional & scientific | 2011 |
| David Snaith Limited | Other services | 2013 |
| Davison Courier Service Ltd | Transport & logistics | 2026 |
| Dcpl | Administrative & support | 2021 |
| DE Joinery Limited | Construction | 2026 |
| Dean Riley Ltd | Construction | 2004 |
| Deckeduk Ltd | Construction | 2025 |
| Degen Closer Ltd | Education | 2026 |
| DEK Group NE Ltd | Financial services | 2023 |
| Delicious Deli Sea Road Limited | Hospitality | 2024 |
| Denise ANN Consultancy Ltd | Health & social care | 2025 |
| Denore Trading Limited | Professional & scientific | 2013 |
| Dent-Tek Ltd | Wholesale & retail | 2012 |
| Derwentdale Engineering Limited | Manufacturing | 1986 |
| Design and Build Nation Wide Ltd | Construction | 2026 |
| Destinova Travel Ltd | Administrative & support | 2023 |
| Devonshire Store Ltd | Wholesale & retail | 2025 |
| Dexter B Health & Leisure Limited | Arts & recreation | 2025 |
| Dexter B Leisure Ltd | Arts & recreation | 2019 |
| DF INT Limited | Manufacturing | 2001 |
| Dhillons Fish Grill (Ouston) Ltd | Hospitality | 2024 |
| Dhillons Peri Peri Ltd | Hospitality | 2025 |
| Diamond H Lifting Equipment Ltd | Manufacturing | 2012 |
| Diamond Search & Selection Ltd | Administrative & support | 2025 |
| Digital Safety CIC | Information & communication | 2020 |
| Dipton Care Home Limited | Health & social care | 2009 |
| Distribution Project Services Ltd | Energy | 2022 |
| Diva Designs for YOU Limited | Other services | 2025 |
| Dive Raid UK Limited | Administrative & support | 2014 |
| DJW Trading Ltd | Wholesale & retail | 2024 |
| DKS Retail Trading Limited | Wholesale & retail | 2024 |
| DL Property Sourcing Ltd | Real estate | 2023 |
| DLR North East Ltd | Construction | 2026 |
| DM Essentials Ltd | Wholesale & retail | 2025 |
| DMH Design Ltd | Construction | 2021 |
| DMT Engineering Ltd | Professional & scientific | 2023 |
| Domdom Productions Ltd | Information & communication | 2023 |
| Donnelly Family Holdings UK Ltd | Real estate | 2021 |
| Dons Prop Holdings Limited | Financial services | 2024 |
| Door 25 Properties Ltd | Real estate | 2017 |
| Doras Explorers Ltd | Agriculture & fishing | 2023 |
| DOW Storey Limited | Wholesale & retail | 2010 |
| DR Donnelly Holdings Ltd | Financial services | 2021 |
| Dr.Susan Cooper Ltd | Other services | 2012 |
| Drake Freight Ltd | Transport & logistics | 2018 |
| Drake's Logistics Ltd | Transport & logistics | 2025 |
| Dream Big Children's Play Centre Ltd | Hospitality | 2023 |
| Dream Team Competitions Ltd | Arts & recreation | 2025 |
| Drewmas Building Ltd | Construction | 2019 |
| Drewplough Limited | Hospitality | 2011 |
| Drilling Project Services Limited | Administrative & support | 2012 |
| Drinks Consulting Limited | Professional & scientific | 2009 |
| Drive Electrical Limited | Construction | 2019 |
| Driving Test Solutions Limited | Education | 2019 |
| Drmd Investment Group Ltd | Financial services | 2026 |
| Drop Supps Ltd | Wholesale & retail | 2025 |