| Innvillageaug Ltd | Hospitality | 2023 |
| Innvillagecly Ltd | Construction | 2021 |
| Innvillageebr Ltd | Hospitality | 2021 |
| Innvillageinn Ltd | Hospitality | 2023 |
| Interactive Trading Group Ltd | Information & communication | 2013 |
| Interiors at Work (UK) Ltd | Manufacturing | 2026 |
| Intermodal Innovations Ltd | Professional & scientific | 2023 |
| Intershoot Limited | Wholesale & retail | 2015 |
| Invigilo Investments Ltd | Construction | 2020 |
| Iperform Sports Physiotherapy & Performance Ltd | Health & social care | 2025 |
| Ireland Spray Foam Insulation Ltd | Construction | 2021 |
| Irish Aroma Botanicals Ltd | Manufacturing | 2023 |
| Irish Craft Malts Ltd | Manufacturing | 2024 |
| Irish Dancing for Adults CIC | Education | 2024 |
| Islandreagh Apartment Management (Number 4) Company Limited | Real estate | 2005 |
| IX Network Global Ltd | Information & communication | 2026 |
| J & B Frost Enterprises Ltd | Financial services | 2020 |
| J & L Properties (NI) Ltd | Real estate | 2014 |
| J & L Wilson Developments Limited | Construction | 1989 |
| J & M Farms Ltd | Wholesale & retail | 2013 |
| J & M. Begley (Building Contractors) Limited | Construction | 1983 |
| J & N Mcmanus Ltd | Construction | 2003 |
| J & R Electrical (N.I.) Ltd | Administrative & support | 2011 |
| J E Kelly & Sons Limited | Agriculture & fishing | 2000 |
| J J Meegan Ltd | Professional & scientific | 2017 |
| J Mcaleer & Sons Ltd | Wholesale & retail | 2005 |
| J P Duddy & Sons Limited | Real estate | 1972 |
| J&J Mcenhill Holdings Ltd | Financial services | 2023 |
| J&J Mcenhill Property Ltd | Real estate | 2023 |
| J-Tech Chemicals Ltd | Wholesale & retail | 2023 |
| J. Mckervey & Sons Ltd | Wholesale & retail | 2022 |
| J.B.C. Plastering Limited | Construction | 2014 |
| J.C.M.G. Developments (NTS) Ltd | Construction | 2009 |
| J.G. Fleming LLP | | 2006 |
| J.M.G. Systems Ltd | Manufacturing | 2001 |
| Jack and Jill Community Playgroup | Education | 2004 |
| James Boylan Safety (NI) Limited | Manufacturing | 1958 |
| James Mcnulty & Co Limited | Professional & scientific | 2011 |
| Jamm 2 Ltd | Hospitality | 2019 |
| Jamm Home Bakery (Omagh) Ltd | Hospitality | 2016 |
| Jammrock Limited | Households | 2023 |
| Jana International Ltd | Mining & quarrying | 2024 |
| Janard Properties Limited | Real estate | 2001 |
| JB Barrett Tractors Limited | Wholesale & retail | 2015 |
| JB Plant (Holdings) Ltd | Other services | 2013 |
| JCH Properties Ireland Limited | Administrative & support | 2015 |
| Jcon Construction Ltd | Construction | 2020 |
| JD O'Hagan Consulting Engineers Ltd. | Professional & scientific | 2021 |
| JD Project Developments Ltd | Construction | 2025 |
| JDM (Omagh) | Professional & scientific | 2015 |
| JEA Group Ltd | Wholesale & retail | 2024 |
| JH Agri Engineering NI Ltd | Professional & scientific | 2025 |
| Jhmc Property Ltd | Real estate | 2024 |
| JJ Mcenhill & Associates Ltd | Health & social care | 2023 |
| Jjdenergysolutions Ltd | Wholesale & retail | 2025 |
| JJH Plant Hire Ltd | Construction | 2018 |
| Jjjak Properties Limited | Real estate | 2019 |
| JJS Engineering (Castlederg) Ltd | Professional & scientific | 2016 |
| Jkel Sales Ltd | Arts & recreation | 2025 |
| JL Doyle Property Ltd | Real estate | 2025 |
| JM Hans Properties Ltd | Real estate | 2025 |
| JM Tyres (NTS) Ltd | Wholesale & retail | 2016 |
| JMA Agri Plant Hire Ltd | Administrative & support | 2024 |
| JMD Turbine Limited | Energy | 2016 |
| JMF Surveys Limited | Professional & scientific | 2016 |
| JMG Fabrication Ltd | Manufacturing | 2023 |
| JMG Renewable Solutions Ltd | Professional & scientific | 2026 |
| JMK Omagh Ltd | Construction | 2020 |
| JMM Retail Ltd | Wholesale & retail | 2018 |
| JN Joinery Ltd | Manufacturing | 2021 |
| John Mann & Co. Ltd | Manufacturing | 1999 |
| John Martin Films Ltd | Information & communication | 2023 |
| Johnny Windscreen's Ltd | Wholesale & retail | 2008 |
| Johnston & Nethery Holdings Ltd | Financial services | 2023 |
| Johnston Car Transport Limited | Transport & logistics | 2010 |
| Jordans Quarries Ltd | Mining & quarrying | 2025 |
| Jp's Hot Grill Ltd | Hospitality | 2025 |
| JPC Conlon Ltd | Financial services | 2024 |
| JPD Builders Ltd | Construction | 2020 |
| JPD Contracts (N.I.) Ltd | Construction | 2017 |
| JPD Gortin Limited | Wholesale & retail | 2024 |
| Jpwg Properties Ltd | Real estate | 2024 |
| JRB Motors Ltd | Wholesale & retail | 2015 |
| JS II Ltd | Administrative & support | 2007 |
| JSB Logistics Ltd | Transport & logistics | 2025 |
| Jsms Cattle Ltd | Agriculture & fishing | 2025 |
| JSP Farms Limited | Agriculture & fishing | 2023 |
| JSR Aviary Ltd | Hospitality | 2026 |
| JSR Capital Contracts Ltd | Construction | 2026 |
| JSR Capital Holdings Ltd | Financial services | 2026 |
| JSR Capital Ventures Ltd | Financial services | 2026 |
| JSR Equine Ltd | Agriculture & fishing | 2026 |
| JTS Property Ltd | Real estate | 2020 |
| Julian Cooke Limited | Wholesale & retail | 2017 |
| Just on Hire Ltd | Administrative & support | 2016 |
| JWA Livestock Ltd | Agriculture & fishing | 2021 |
| JWD Farms Limited | Agriculture & fishing | 2016 |
| K - Stone Ireland Limited | Wholesale & retail | 2017 |
| K Dash Ltd | Professional & scientific | 2023 |
| K Mccoy Ltd | Construction | 2013 |