| Northumberland Electrical Solutions Limited | Construction | 2013 |
| Northumberland Pride Limited | Other services | 2018 |
| Northumbria Rentals Ltd | Real estate | 2026 |
| Northumbria Waste Recycling Ltd | Water & waste | 2024 |
| Northumbrian Citizens Advice Bureau | Information & communication | 2013 |
| Northumbrian Engineering Soulutions Ltd | Manufacturing | 2021 |
| Northumbrian Groundwork Services Limited | Construction | 2020 |
| Northumbrian Ice Cream Company Limited | Manufacturing | 1994 |
| Northumbrian Realty Limited | Real estate | 2025 |
| Nosherwan Enterprises Limited | Hospitality | 2025 |
| NSD Investments Limited | Financial services | 2023 |
| NST Welding (UK) Limited | Wholesale & retail | 1996 |
| NTP Halo Limited | Administrative & support | 2015 |
| Nurtch Ltd | Hospitality | 2022 |
| Nurun Nessa (NE) Ltd | Hospitality | 2025 |
| Ocean 168 Ltd | Hospitality | 2013 |
| Ocho Property Rentals Ltd | Real estate | 2024 |
| Offshore Mechanical Engineering Limited | Administrative & support | 2019 |
| OGH Services Ltd | Professional & scientific | 2026 |
| ON Site Tyre Repairs Limited | Wholesale & retail | 2007 |
| Oplum Limited | Information & communication | 2021 |
| Optima Strive Ltd | Professional & scientific | 2025 |
| Opus Global Tech Ltd | Extraterritorial | 2020 |
| Ormesby Road Holidays Limited | Real estate | 2021 |
| OUT There Environments Ltd | Professional & scientific | 2021 |
| Outdoor Living Systems Ltd | Construction | 2023 |
| Outlines Design Limited | Professional & scientific | 2015 |
| Outrams Garage Ltd | Extraterritorial | 2018 |
| P I B Trans Ltd | Transport & logistics | 2018 |
| P Rusby Consultancy Ltd | Education | 2025 |
| Paddock Investment Properties Ltd | Real estate | 2024 |
| Paige’S Beauty Lounge Ltd | Other services | 2023 |
| Pallister & Co Ltd | Water & waste | 2012 |
| Party Point Ltd | Arts & recreation | 2025 |
| Past to Present Construction Ltd | Construction | 2020 |
| Pavo HC Limited | Hospitality | 2025 |
| Pawfect Dog Walks Ltd. | Other services | 2015 |
| Pawfectly Natural Limited | Wholesale & retail | 2023 |
| PAX Mediation Limited | Professional & scientific | 2012 |
| Pdsr Pharma Consulting Ltd | Professional & scientific | 2024 |
| Perception Deception Limited | Information & communication | 2012 |
| Persistence Motor Trade Ltd | Wholesale & retail | 2023 |
| Pets and Paws Limited | Wholesale & retail | 2024 |
| Pettigrew Properties Ltd | Real estate | 2025 |
| PF Fitting and Bolting Services Ltd | Extraterritorial | 2024 |
| Phillips Commissioning Services Limited | Professional & scientific | 2003 |
| Phillips Design Limited | Manufacturing | 2001 |
| Pink Rose Ashington Limited | Hospitality | 2025 |
| Pipes & Wire (NE) Ltd. | Construction | 2013 |
| Pitman Food Ltd | Hospitality | 2026 |
| PMX Decor Ltd | Construction | 2025 |
| PNV Inspiration Limited | Wholesale & retail | 2026 |
| Pokerealm TCG Ltd | Wholesale & retail | 2025 |
| Polar Krush Group Limited | Professional & scientific | 2018 |
| Portland Highway Consultants Ltd | Professional & scientific | 2016 |
| Portland Paving & Groundworks Ltd | Construction | 2019 |
| Power and Heat Ltd | Professional & scientific | 2025 |
| Power, Utilities Project Management Services Ltd | Professional & scientific | 2023 |
| Powered by Vision Limited | Information & communication | 1999 |
| Premteq Ltd | Information & communication | 2021 |
| Primeaxis Hub Ltd | Wholesale & retail | 2025 |
| Pro-Pave Surfacing Ltd | Administrative & support | 2023 |
| Proactive Office Solutions Ltd | Real estate | 2025 |
| Probooks Accountants Ltd | Professional & scientific | 2025 |
| Product Valley Ltd | Wholesale & retail | 2025 |
| Project Advisors International (U.K.) Ltd. | Administrative & support | 2003 |
| Project U Fitness Trading Ltd | Arts & recreation | 2019 |
| Prthiksha Ltd | Manufacturing | 2025 |
| Punch-Drunk Group Limited | Hospitality | 2024 |
| Pure Pressure - Exterior Solutions Ltd | Administrative & support | 2025 |
| Pushh Ltd | Wholesale & retail | 2025 |
| PWG Connections Group Limited | Construction | 2025 |
| PWG Connections Ltd | Construction | 2007 |
| PWG Investments Limited | Financial services | 2025 |
| QCD Precision Limited | Manufacturing | 2017 |
| Quality Matters Consultancy Limited | Professional & scientific | 2026 |
| Quantum Personal Computers Ltd | Manufacturing | 2019 |
| R & D Homes Newcastle Ltd | Real estate | 2017 |
| R a Events (NE) Limited | Arts & recreation | 2025 |
| R Masters Joinery Ltd | Manufacturing | 2020 |
| R. Thornton & Co. Ltd. | Construction | 1992 |
| RA Monster Events Ltd | Arts & recreation | 2024 |
| Racking Safety Solutions Limited | Manufacturing | 2011 |
| Rail Holdings Limited | Administrative & support | 2004 |
| Rail Properties Limited | Real estate | 2019 |
| Railway Electrification & Maintenance Engineers Limited | Construction | 2016 |
| Rainbow Properties North Ltd | Households | 2021 |
| Randhawa Blocks Ltd | Real estate | 2025 |
| Randhawa Junction Ltd | Wholesale & retail | 2025 |
| Range Plumbing & Heating Ltd | Construction | 2011 |
| Rawardengineering Ltd | Wholesale & retail | 2025 |
| Raytec Limited | Manufacturing | 2005 |
| Rcharlton Relational Solutions Ltd | Information & communication | 2026 |
| Rearnthai Massage & Spa Ltd | Other services | 2024 |
| RED4 Developments Limited | Construction | 2021 |
| RED4 Properties Limited | Real estate | 2025 |
| Rental Properties North Ltd | Households | 2021 |
| Renée's Bar Ltd | Hospitality | 2026 |
| Repurposeful CIC | Wholesale & retail | 2022 |
| Reviver Limited | Wholesale & retail | 2026 |