| Mullan Drilling Ltd | Agriculture & fishing | 2017 |
| NC Building Limited | Construction | 2017 |
| Ncep Management Services Limited | Real estate | 2020 |
| NI Cargo Ltd | Transport & logistics | 2025 |
| NI Couriers Ltd | Transport & logistics | 2012 |
| NI Sports Medics Services Ltd | Health & social care | 2026 |
| Nipato Limited | Hospitality | 2015 |
| Nitour Ltd | Wholesale & retail | 2017 |
| NJB Couriers Ltd | Transport & logistics | 2018 |
| Nook Living Ltd | Wholesale & retail | 2017 |
| NOR Consulting Limited | Professional & scientific | 2019 |
| Northern Ireland Water Alpha Limited | Water & waste | 2004 |
| Northside Pallet Warehouse Ltd | Wholesale & retail | 2025 |
| Northview Property Management Ltd | Real estate | 2014 |
| Noya (UK) Ltd | | 2001 |
| Nutts Corner Services Ltd | Wholesale & retail | 2018 |
| Nutts Corner Tyres & Breakdown Services Ltd | Wholesale & retail | 2024 |
| Oaktree Security Services Limited | Administrative & support | 2017 |
| OCD Drinks Inc Limited | Hospitality | 2024 |
| Oliver Edward Mcdaniel Limited | Extraterritorial | 2025 |
| Opal People Solutions Ltd | Administrative & support | 2019 |
| Optimman Ltd | Professional & scientific | 2016 |
| Outline Architectural Services Limited | Professional & scientific | 2019 |
| Oyster Bay Holiday Apartment Dundrum Ltd | Hospitality | 2024 |
| Page Turners Studio Ltd | Information & communication | 2021 |
| Pakenham Community Limited | Arts & recreation | 2019 |
| Paragon Trucks Ltd | Wholesale & retail | 2011 |
| Pathcode Ltd | Information & communication | 2025 |
| Patriot Home of Rock CIC | Hospitality | 2020 |
| Patterson Ring Rolling Ltd | Manufacturing | 2017 |
| Peak Platform Websites Ltd | Information & communication | 2024 |
| Pearl Assosiates Limited | Health & social care | 2024 |
| Pectus Group Ltd | Health & social care | 2020 |
| PEP Therapies Limited | Health & social care | 2019 |
| Pharmameddev Services Ltd | Professional & scientific | 2021 |
| Philip Lucas Consulting Ltd | Professional & scientific | 2009 |
| Photo Booth Marketing Limited | Other services | 2021 |
| Pinnacle Private Health NI Ltd | Health & social care | 2023 |
| PLY Design & Fit Ltd | Professional & scientific | 2016 |
| PMC Deliveryteam (NI) Ltd | Transport & logistics | 2019 |
| Port Commercials Ltd | Manufacturing | 2007 |
| Post Pieces Limited | Arts & recreation | 2019 |
| Powerworx NI Ltd | Professional & scientific | 2022 |
| Premier Laundry Equipment Limited | Wholesale & retail | 2019 |
| Premierfirst Vehicle Rental UK Limited | | 1996 |
| Premium 3A Parks Ltd | Transport & logistics | 2024 |
| Priceblitzuk Ltd | Wholesale & retail | 2020 |
| Priority Costumes Limited | Information & communication | 2025 |
| Project Giant Ltd | Wholesale & retail | 2022 |
| Proseal Conservatories & Windows Ltd | Manufacturing | 2003 |
| Protex Windows Limited | Wholesale & retail | 1989 |
| Quantum AI Consulting Ltd | Information & communication | 2026 |
| Quarry Works Ltd | Construction | 2016 |
| Quell.Io Limited | Information & communication | 2018 |
| QV Solutions NI Ltd | Real estate | 2017 |
| R Best Engineering Ltd | Professional & scientific | 2025 |
| R. L. Trading Ireland Ltd | Other services | 2023 |
| R.J. Lagan Limited | Real estate | 2014 |
| Randox (Alexander Road) Limited | Financial services | 2022 |
| Randox Estates Limited | Real estate | 2018 |
| Randox Farming Limited | Real estate | 2012 |
| Randox Food Diagnostics Limited | Extraterritorial | 2008 |
| Randox Health Checks (NI) Ltd | Health & social care | 2012 |
| Randox Health Limited | Extraterritorial | 2018 |
| Randox Holdings Limited | Manufacturing | 2012 |
| Randox Land Limited | Agriculture & fishing | 2012 |
| Randox Research Environment Limited | Health & social care | 2022 |
| Randox Testing Services Ltd | Extraterritorial | 2012 |
| Randox Toxicology Ltd | Extraterritorial | 2011 |
| Ranna Services Ltd | Hospitality | 2019 |
| Ravara Developments Limited | Construction | 2007 |
| Ravara Properties Limited | Construction | 2002 |
| RC Finance & Leasing Limited | Administrative & support | 2016 |
| RCJ Collins Ltd | Real estate | 2022 |
| RDX Engineering Ltd | Professional & scientific | 2026 |
| REA Sawmills Ltd | Manufacturing | 2014 |
| REA Timber Craft Limited | Manufacturing | 2014 |
| Recycle Engineeering Company Limited | Construction | 1995 |
| Red Stag Catering Limited | Hospitality | 2016 |
| Relinea EOT Limited | Extraterritorial | 2022 |
| Renegade Martial Arts Academy Ltd | Education | 2026 |
| RLC Langford Lodge Limited | Manufacturing | 2017 |
| RM Construction & Civils Ltd | Construction | 2025 |
| Rockdale Enterprises Limited | Information & communication | 2013 |
| Rockhold Lime Ltd | Construction | 2026 |
| RPM Motors (N.I.) Limited | Wholesale & retail | 2020 |
| Røast Coffee and Bakes Ltd | Hospitality | 2024 |
| S Moore Building Contractors Ltd | Construction | 2021 |
| S.A.R.R.G. Limited | Hospitality | 2016 |
| S.W.C. Restaurants Limited | Hospitality | 1995 |
| Safety Haven Ltd | Construction | 2024 |
| Saine Engineering Ltd. | Professional & scientific | 2026 |
| Serviced Apartment Agent Limited | Administrative & support | 2021 |
| SEW in a Box Ltd | Professional & scientific | 2021 |
| Sharons Confectionery Ltd | Wholesale & retail | 2024 |
| Shoreline Medical Ltd | Health & social care | 2025 |
| Signature Architectural Panelling NI Ltd | Construction | 2026 |
| Signstik Limited | Manufacturing | 1998 |
| Silverline Wedding Cars Group NI Ltd. | Transport & logistics | 2025 |
| Simucare Ltd | Manufacturing | 2024 |