| GLO Rentals Ltd | Real estate | 2026 |
| GLO Sunbed Hire Limited | Other services | 2018 |
| GLO Tanning Lounge Limited | Other services | 2018 |
| Global Freight (N.I.) Ltd | Transport & logistics | 2012 |
| Global N.D.T. Inspections Limited | Construction | 2014 |
| GM Construction (N.I.) Limited | Construction | 2020 |
| GM QA Ltd | Professional & scientific | 2024 |
| GM Walltracking Banbridge Ltd | Construction | 2013 |
| GMF Property Management Ltd | Real estate | 2024 |
| Golden Bridge Banbridge Ltd | Hospitality | 2025 |
| Golfkeel Ltd | Real estate | 2025 |
| Goodland Limited | Construction | 2016 |
| Gordon Watson Agencies Limited | Wholesale & retail | 2011 |
| Gordons Chemists Holdings (Northern Ireland) Ltd | Wholesale & retail | 2021 |
| Gordons Property Management Ltd | Real estate | 2026 |
| Gosford Developments Limited | Real estate | 2014 |
| Grace Generation | Other services | 2012 |
| Graham Plant Painting Ltd | Wholesale & retail | 2019 |
| Granville Limited | Real estate | 2019 |
| Green Bean (N.I.) Limited | Wholesale & retail | 1998 |
| Green Heating Solutions Ltd | Construction | 2022 |
| Green Marine Ireland Ltd | Construction | 2018 |
| Greenfield Development Group Ltd | Construction | 2017 |
| Grenadier Investment Management Limited | Financial services | 2017 |
| Greyford Holdings Ltd | Financial services | 2025 |
| Groom in Your Room Ltd | Other services | 2013 |
| Ground Electrical Ltd | Energy | 2018 |
| GT Total Renovations Ltd | Construction | 2026 |
| GWA Supplies Limited | Wholesale & retail | 2011 |
| Gym Kraft Limited | Arts & recreation | 2025 |
| H and O. DC Ltd | Construction | 2023 |
| Hadden Homes Limited | Real estate | 2019 |
| Hadm Ltd | Construction | 2019 |
| Haemoband Surgical Ltd | Manufacturing | 2000 |
| Hagan Medical Services Ltd | Health & social care | 2024 |
| Hallsmill Properties Ltd | Real estate | 2014 |
| Handley Heating Services Limited | Extraterritorial | 2004 |
| Harsen&Co. Limited | Construction | 2025 |
| Hawthorne Consulting Limited | Professional & scientific | 2012 |
| Hayes E-Commerce Ltd | Wholesale & retail | 2023 |
| Hb&R Ltd | Hospitality | 2023 |
| Helix Hearing Ltd | Wholesale & retail | 2026 |
| Henry Promotions Limited | Professional & scientific | 2024 |
| HHS (NI) Ltd | Transport & logistics | 2013 |
| Highmoon Developments Limited | Real estate | 2006 |
| Hill Road Commercials Ltd | Wholesale & retail | 2020 |
| Hilldale Services IRL Limited | Agriculture & fishing | 2013 |
| Hillview Developments (N.I.) Ltd | Construction | 2021 |
| Hire IT Access and Equipment Ltd | Administrative & support | 2025 |
| HJW Properties Limited | Real estate | 2016 |
| Holleran Holdings Ltd | Financial services | 2017 |
| Home-Start Banbridge | Health & social care | 2013 |
| Homes for Life (NI) Limited | Construction | 2015 |
| Homeworld Property Services Ltd | Construction | 2016 |
| Hoof Shop Ltd | Wholesale & retail | 2024 |
| Horsepower Contracts Ltd | Construction | 2025 |
| Houston Stores Limited | Professional & scientific | 2013 |
| Hunter Sinton LLP | | 2020 |
| Huntly Stores Ltd | Wholesale & retail | 2023 |
| I M G Construction Ltd | Construction | 2014 |
| IH Car Sales Ltd | Wholesale & retail | 2025 |
| Illuminate Digital N.I Ltd | Professional & scientific | 2025 |
| IMC Building Developments Limited | Financial services | 2025 |
| IMC Glass Ltd | Manufacturing | 2014 |
| Impact I.T for ALL Ltd | Education | 2024 |
| Impero Investments Limited | Administrative & support | 2022 |
| Infinity Adventure Park Ltd | Arts & recreation | 2019 |
| Inis Architects Ltd | Professional & scientific | 2018 |
| Innisfree Property Limited | Real estate | 2026 |
| Innovative Talent Solutions Ltd | Administrative & support | 2021 |
| Inprio Ltd | Real estate | 2018 |
| Insight Consulting (NI) Limited | Information & communication | 2013 |
| Inspira Holdings Ltd | Financial services | 2020 |
| Instyle Carpets Ltd | Wholesale & retail | 2023 |
| Intelligent Home (NI) Limited | Manufacturing | 2012 |
| Investment 24 Ltd | Real estate | 2007 |
| IP Register NI Limited | Professional & scientific | 2026 |
| Irish Linen Guild-The | Professional & scientific | 1968 |
| Iveagh Enterprises Ltd | Real estate | 2012 |
| Iveagh Funeral Services Ltd | Other services | 2020 |
| Iveagh Leisure Ltd | Administrative & support | 2009 |
| Iveagh Ltd | Administrative & support | 2021 |
| Ivex Construction Ltd | Construction | 2012 |
| Ivory Clinic Ltd | Other services | 2020 |
| Izzat Electrical Engineering Limited | Construction | 2025 |
| J & Sons Roofing Ltd | Construction | 2025 |
| J.A.Lyttle Limited | Wholesale & retail | 2024 |
| J.D. O’Hare & Sons Limited | Agriculture & fishing | 2018 |
| J.D. O’Hare Contracting Limited | Construction | 2018 |
| J.F. Tiling & Surface Repairs Ltd | Construction | 2024 |
| J.P. Transport (N.I.) Limited | Transport & logistics | 2016 |
| J29 Project Ltd | Other services | 2018 |
| Jacni Ltd | Financial services | 2025 |
| JAO Contracts Ltd | Construction | 2016 |
| Jayne Murray PR Ltd | Professional & scientific | 2019 |
| JBT Subtrading Limited | Hospitality | 2014 |
| JC Donald (Farms) Limited | Agriculture & fishing | 2020 |
| JC Donald Ltd | Agriculture & fishing | 2018 |
| Jerks Property Ltd | Real estate | 2024 |
| JES N.I. Ltd | Real estate | 2026 |