| Cvbay Limited | Administrative & support | 2006 |
| CVC Car & Commercial Body & Trim Repairs Ltd | Manufacturing | 2007 |
| CW Car Care Limited | Wholesale & retail | 2024 |
| CW Hair Ltd | Other services | 2024 |
| CW Tiling and Bathrooms Limited | Construction | 2024 |
| CWG Sheetmetal Ltd | Manufacturing | 2013 |
| CWI 002 Ltd | Financial services | 2023 |
| Cwit Business Services Ltd | Information & communication | 2025 |
| CWS Electrical Services Ltd | Construction | 2016 |
| Cxpsy Labs Limited | Information & communication | 2025 |
| CY Partners LLP | | 2008 |
| CY Partners Recruitment Ltd | Administrative & support | 2011 |
| Cyber Edge PVT Ltd | Wholesale & retail | 2025 |
| Cyber Guard Consulting Limited | Information & communication | 2022 |
| Cyber Shelter Limited | Professional & scientific | 2017 |
| Cyberflux Limited | Information & communication | 2026 |
| Cyberqube EOT Limited | Extraterritorial | 2022 |
| Cyberqube Limited | Information & communication | 1984 |
| Cybit Group Limited | Financial services | 2018 |
| Cybit Limited | Information & communication | 1991 |
| Cybit South Limited | Information & communication | 1998 |
| CYC (NE) Ltd | Hospitality | 2025 |
| Cycle Centre Newcastle Limited | Wholesale & retail | 2014 |
| Cyclelogical (Newcastle) Limited | Wholesale & retail | 2004 |
| Cygnet Developments Limited | Real estate | 2025 |
| Cyrus Newcastle Ltd | Wholesale & retail | 2020 |
| Cyrus Pattinson Boxing Academy CIC | Arts & recreation | 2025 |
| Cystel Limited | Information & communication | 2018 |
| Cytology Services Limited | Health & social care | 2021 |
| Czar Properties Limited | Real estate | 2002 |
| Czbeatsprods Limited | Information & communication | 2025 |
| CØH Visuals Limited | Information & communication | 2023 |
| D & B Assets Ltd | Professional & scientific | 2015 |
| D & D Book-Keeping & Accountancy Ltd | Professional & scientific | 2010 |
| D & D Clean Ltd | Administrative & support | 2012 |
| D & J Plumbing and Heating Limited | Construction | 2006 |
| D & JJ Limited | Real estate | 2013 |
| D & L Trading Warehouse Ltd | Wholesale & retail | 2021 |
| D & M (Newcastle) Limited | Real estate | 2013 |
| D & R Property Renovation Ltd | Construction | 2026 |
| D a Jones TV Broadcast Ltd | Information & communication | 2020 |
| D a K Heating Limited | Construction | 2020 |
| D a K Heating Services Limited | Construction | 2026 |
| D B Property Foundations Ltd | Real estate | 2017 |
| D Barrett Consulting Services Ltd | Information & communication | 2024 |
| D Burns Interiors Ltd | Construction | 2022 |
| D Carr Construction Ltd | Construction | 2015 |
| D E Reay Services Ltd | Professional & scientific | 2014 |
| D G a Project Management Limited | Professional & scientific | 2009 |
| D G Young Limited | Real estate | 2018 |
| D G Young Property Management Ltd | Real estate | 2021 |
| D Green Electrical Ltd | Construction | 2025 |
| D H Thompson Ltd | Financial services | 2016 |
| D Horst Driving School Limited | Education | 2025 |
| D J L Electricalservices Limited | Construction | 2014 |
| D K & L R Davison Ltd | Health & social care | 2015 |
| D M K Retailers Ltd | Wholesale & retail | 2026 |
| D N Taylor Ltd | Construction | 2023 |
| D Nesting Solutions Limited | Real estate | 2023 |
| D P (North East) Limited | Construction | 2020 |
| D Rainbow Offshore Limited | Construction | 2019 |
| D Robson & Associates Limited | Real estate | 2004 |
| D Robson Property Management Limited | Real estate | 2004 |
| D S Henderson Consulting Ltd | Information & communication | 2014 |
| D Sopp Consultancy Limited | Professional & scientific | 2023 |
| D T Buchan Limited | Professional & scientific | 2007 |
| D T W Estates Ltd | Real estate | 2025 |
| D W Projects Limited | Extraterritorial | 1993 |
| D&B Rentals Ltd | Real estate | 2018 |
| D&C Couriers Ltd | Transport & logistics | 2020 |
| D&D Construction North East Limited | Construction | 2020 |
| D&D RAW and More Ltd | Wholesale & retail | 2024 |
| D&D Retail and Services Ltd | Wholesale & retail | 2024 |
| D&G Ceilings & Partitions Ltd | Construction | 2017 |
| D&G Forster Property Developers Limited | Construction | 1996 |
| D&G Motor Engineers Ltd | Wholesale & retail | 2013 |
| D&L Maintenance Ltd | Construction | 2025 |
| D&L Woricker Ltd | Health & social care | 2017 |
| D&M Lighthouse Healthcare Limited Limited | Health & social care | 2019 |
| D&S Joinery Services Ltd | Construction | 2019 |
| D&Tbs Ltd | Professional & scientific | 2024 |
| D&W Cronin Properties Limited | Real estate | 2017 |
| D'Addario UK Limited | Wholesale & retail | 2009 |
| D'Monik Ltd | Information & communication | 2014 |
| D-Lab Electronics Ltd | Professional & scientific | 2020 |
| D. a. Catering Limited | Hospitality | 2014 |
| D. Collard Limited | Wholesale & retail | 1984 |
| D. J. H. Agencies Ltd | Administrative & support | 2010 |
| D. T. Ward Limited | Construction | 2007 |
| D.A.K. Tipper Hire Limited | Transport & logistics | 2003 |
| D.B. Joinery & Construction Ltd | Construction | 2022 |
| D.G.Chalk Limited | Real estate | 1950 |
| D.M Scaffolding Ltd | Construction | 2026 |
| D.M.B. Contractors Limited | Wholesale & retail | 1983 |
| D.O.L Ventures Ltd | Wholesale & retail | 2026 |
| D.R. Wood & Sons Limited | Transport & logistics | 1956 |
| D.S.P&R Ltd | Construction | 2023 |
| D.T.D. Paintless Dent Removals Ltd | Wholesale & retail | 2005 |
| D2 Youth Zone Ltd | Other services | 1995 |
| D3 (Childcare) Limited | Real estate | 2018 |