| GM Sealant Solutions Ltd | Construction | 2017 |
| Golden EGG Marketing Limited | Information & communication | 2013 |
| Gordon Estates Management Limited | Real estate | 2015 |
| Gorman Close Land Management Ltd | Households | 2021 |
| Gortmerron Land Management Ltd | Extraterritorial | 2004 |
| Grade 3 Security Limited | Administrative & support | 2014 |
| Graham Trailer Services Ltd | Manufacturing | 2012 |
| Grampian Properties Limited | Real estate | 2005 |
| Grange Manor Antrim Management Ltd | Extraterritorial | 2011 |
| Granted AGA Limited | Information & communication | 2024 |
| Greater Ballyclare Youth for Christ | Other services | 2013 |
| Greenbee Enterprises Ltd | Manufacturing | 2015 |
| Greenhall Court Management (NO. 2) Ltd | Households | 2010 |
| Greenisland Manor Management Company Limited | Extraterritorial | 2000 |
| Greenvale Mews Management Company Ltd | Extraterritorial | 2007 |
| Grey Brow Holdings Limited | Health & social care | 2020 |
| GT Hvac Sales Ltd | Construction | 2010 |
| Guildstone Limited | Real estate | 1971 |
| Gundyco Limited | Extraterritorial | 2025 |
| H&H Wind Murnells Ltd | Energy | 2014 |
| H2YDRO Limited | Construction | 2020 |
| Hagan Homes Limited | Agriculture & fishing | 1988 |
| Halfpenny Gate Lane Management Ltd | Households | 2016 |
| Hamill Mechanical Ltd | Wholesale & retail | 2022 |
| Hammer Tech (NI) Limited | Wholesale & retail | 2007 |
| Handel Export Limited | Professional & scientific | 2021 |
| Hansons Hall Management Ltd | Households | 2019 |
| Harbinson Mews Limited | Extraterritorial | 2001 |
| Harbour Road (Carnlough) Ltd | Households | 2025 |
| Harcon Removals Ltd | Transport & logistics | 2016 |
| Harphall Ltd | Hospitality | 2017 |
| Harri Vent Control Ltd | Manufacturing | 2018 |
| Harryville Inns Ltd | Hospitality | 2017 |
| Haulage Services Limited | Transport & logistics | 2019 |
| Hawthorn Hall Management Ltd | Extraterritorial | 2016 |
| Heatboss Limited | Extraterritorial | 2014 |
| Heatrightservices Ltd | Construction | 2026 |
| HEN House 43 Limited | Hospitality | 2024 |
| Henley Management Company (Cultra) Limited | Households | 2020 |
| High Tower Press Ltd | Information & communication | 2020 |
| Highgrove Meadows (Phase 2) Management Co Ltd | Households | 2018 |
| Hillcrest Management Company (Lurgan) Ltd | Extraterritorial | 2014 |
| Hillcrest Manor Management Company Limited | Extraterritorial | 2004 |
| Hillheadsheds Ltd | Manufacturing | 2012 |
| Hillview Heating & Plumbing Limited | Construction | 2017 |
| Himalayan Curry House Ltd | Hospitality | 2023 |
| Hire-A-Hand Ballyclare Limited | Construction | 2023 |
| HNB Consultants Ltd | Professional & scientific | 2016 |
| Hobbybuilder Coaching Ltd | Health & social care | 2024 |
| Hobson Management Limited | Households | 1998 |
| Holestone Consulting Limited | Information & communication | 2025 |
| Hollow Mills Management Co Ltd | Extraterritorial | 2006 |
| Hollybrook Property Management Company Limited | Extraterritorial | 2004 |
| Hollyburn Management Limited | Extraterritorial | 2006 |
| Holmview Management Company Limited | Extraterritorial | 2007 |
| HOPE365 | Wholesale & retail | 2015 |
| Houston's Coachworks Limited | Manufacturing | 1998 |
| HP82 Ltd | Hospitality | 2016 |
| HT Motors (2019) Ltd | Manufacturing | 2019 |
| Htko Ltd | Hospitality | 2023 |
| Hugh Stevenson's Bakery Limited | Manufacturing | 2019 |
| Huntingdale Developments Limited | Construction | 2023 |
| HVC Group Limited | Energy | 2026 |
| Hyde Park Management Agents Limited | Households | 2005 |
| Hydepark Court Management Limited | Households | 2005 |
| Hydepark Mews Management Company Ltd | Households | 2020 |
| Hyperbarick Recovery Limited | Arts & recreation | 2022 |
| I 2 I Invest Ltd | Information & communication | 2010 |
| IAN Fleck Signs Ltd | Professional & scientific | 2022 |
| IAN Stewart Investigations Ltd | Administrative & support | 2018 |
| ILC23 Ltd | Wholesale & retail | 2024 |
| IN Touch Interactive Ltd | Information & communication | 2015 |
| IN Touch Live Limited | Information & communication | 2020 |
| Inglis Bakery Belfast Limited | Manufacturing | 2019 |
| Inishbeg Enterprises Limited | Construction | 2015 |
| Inspired Furniture Ltd | Manufacturing | 2012 |
| Interior Furnishing Services Ltd | Wholesale & retail | 2020 |
| Invictus International Ltd. | Arts & recreation | 2014 |
| Irhm Limited | Wholesale & retail | 2017 |
| Irish BOY Racer Ltd | Arts & recreation | 2018 |
| Irish Minibike Championship CIC | Arts & recreation | 2020 |
| Irwin Property Developments Ltd | Real estate | 2003 |
| Island Printing & Finishing Equipment Ltd | Manufacturing | 2012 |
| Island View Apartment Management Company Limited | Extraterritorial | 2008 |
| Island View Property Management Co Ltd | Households | 2021 |
| Islandreagh Apartment Management (Number 1) Company Limited | Households | 2005 |
| Islandview Ballycarry Property Management Ltd | Extraterritorial | 2007 |
| J & G Plant Hire Limited | Construction | 2010 |
| J a Hood Ltd | Construction | 2005 |
| J TEC IT Limited | Information & communication | 2018 |
| J. MCM Construction Limited | Construction | 1992 |
| J.B.Kennedy Bakery Limited | Manufacturing | 2019 |
| J.E.M Investments Limited | Real estate | 1982 |
| J.N.G. Agencies Ltd | Extraterritorial | 2006 |
| James Gault Consultancy Limited | Information & communication | 2022 |
| Jbss (Group) Ltd | Construction | 2016 |
| JEM Fleet Services Ltd | Administrative & support | 2022 |
| Jenesis (Driver Awareness) Ltd | Administrative & support | 2022 |
| Jezaro Ltd | Professional & scientific | 2017 |
| JH Flight Limited | Transport & logistics | 2025 |