| Foyle Construction Ltd | Construction | 2025 |
| Foyle Drive Property Management Limited | Households | 2009 |
| Foyle Plumbing Heating Cooling Ltd | Construction | 2021 |
| Foyle View Management Limited | Households | 2000 |
| Fraggie Limited | Real estate | 2013 |
| Frank Owens Ltd | Hospitality | 2002 |
| Friends of Limavady Grammar School Rugby Limited | Education | 2025 |
| Friends of Stendhal Ltd | Arts & recreation | 2011 |
| Fruithill Estates Limited | Other services | 1953 |
| Fruithill Holdings Ltd | Financial services | 2025 |
| Furniture Factory (NW) Ltd | Wholesale & retail | 2018 |
| FVM Contracts Limited | Construction | 2016 |
| G & a Contracts Limited | Construction | 2018 |
| G J Asset Management Limited | Real estate | 2013 |
| G M Holdings (N.I.) Ltd | Real estate | 2015 |
| G.E. Services (LIM) Limited | Construction | 2009 |
| Gaff Developments Ltd | Construction | 2017 |
| Gallion Glen Management Ltd | Households | 2017 |
| Galway Park & Galway Drive Management Limited | Households | 2016 |
| Garvally Management Ltd | Households | 2006 |
| Garvan Court Management Company Ltd | Real estate | 2020 |
| GC Mcalister Services Ltd | Professional & scientific | 2024 |
| Gear Properties Limited | Real estate | 2002 |
| Gelvin Electrics Ltd | Construction | 2024 |
| Genenor Investigations Ltd | Administrative & support | 2021 |
| Geoffjapear Ltd | Financial services | 2018 |
| George Conn & SON Limited | Agriculture & fishing | 1976 |
| Gibson Invest Limited | Financial services | 2023 |
| Gibsons Pharmacy Limited | Wholesale & retail | 2009 |
| Girona Consultants Ltd | Professional & scientific | 2026 |
| Giuis Capital Ltd | Manufacturing | 2025 |
| GKH Engineering Limited | Construction | 2022 |
| GKM Design Services Ltd | Professional & scientific | 2020 |
| Glack MOR Management Company Limited | Households | 2005 |
| Glasvey Old School Management Ltd | Households | 2005 |
| Glebemore Electrical Limited | Construction | 2017 |
| Glenhead Holdings Ltd | Financial services | 2026 |
| Glenhead Properties Limited | Real estate | 2005 |
| Glenvale Management Company Portrush (NO. 2) Limited | Households | 2015 |
| Global Education NI Ltd | Administrative & support | 2007 |
| Glor Leim an Mhadaidh Community Development Group | Education | 2014 |
| GMK DRY Lining Limited | Construction | 2017 |
| Go Safe Driver Training Solutions Limited | Transport & logistics | 2017 |
| Good Shepherd Management Company Limited | Households | 2000 |
| Gort Management Company Limited | Professional & scientific | 2008 |
| Gortenny Glen Management Company Limited | Other services | 2002 |
| Gortin Manor Management Company Limited | Households | 2000 |
| GPF Consultancy Ltd | Administrative & support | 2018 |
| Grace Terra Ltd | Real estate | 2020 |
| Graceland Securities Ltd | Real estate | 2015 |
| Graham Drylining Limited | Construction | 2019 |
| Green Quantity Surveying Ltd | Construction | 2007 |
| Greenhaw Manor Management Ltd | Households | 2009 |
| Greenwood Management Company Limited | Extraterritorial | 2006 |
| Grid Electrical Group Ltd | Construction | 2022 |
| Grid Electrical Services Ltd | Construction | 2016 |
| Grove Manor Management Company Limited | Households | 2019 |
| Guy's Home Interiors Ltd | Manufacturing | 2016 |
| H&E Security Ltd | Administrative & support | 2025 |
| H&N (NW) Ltd | Construction | 2024 |
| H1 Electrical Limited | Construction | 2025 |
| Halpin Consulting Ltd | Professional & scientific | 2020 |
| Hamco Transport (NI) Limited | Transport & logistics | 2016 |
| Hanna Invest Limited | Financial services | 2024 |
| Harbimoore Ltd | Information & communication | 2026 |
| Hare and Hawthorn Ltd | Wholesale & retail | 2024 |
| Harkins of Dunmore Ltd | Energy | 2013 |
| Haslett Biofuel Products Limited | Wholesale & retail | 2012 |
| Haslett Mckeever Limited | Construction | 2019 |
| Hawthornes Land Management Ltd | Households | 2004 |
| HAY Day Investments Limited | Construction | 2012 |
| HCD Contracts Ltd | Construction | 2025 |
| Henry Street Management Company Limited | Households | 2003 |
| Hermesia Ltd | Information & communication | 2025 |
| High Life Access Ltd | Construction | 2023 |
| HJP19 Limited | Real estate | 2025 |
| Hogg Engineering Limavady Ltd | Professional & scientific | 2019 |
| HOL Trading Ltd | Wholesale & retail | 2023 |
| Hollow Hills Management Company Limited | Households | 2022 |
| Home Grid Investments Limited | Real estate | 2024 |
| Home Grid Solar Limited | Construction | 2021 |
| Homepage Estate Agents Limited | Real estate | 2022 |
| Hyde Park Management Agents NO 6 Limited | Households | 2017 |
| Hyde Park Management Agents Pthree Limited | Real estate | 2017 |
| Hyve One Limited | Arts & recreation | 2020 |
| Iappsni Limited | Information & communication | 2019 |
| IGS Management Company Limited | Real estate | 2013 |
| Iharron Consulting Ltd | Administrative & support | 2022 |
| Ikigai 7 Fiduciary Limited | Financial services | 2025 |
| Ikigai 7 Ltd | Professional & scientific | 2025 |
| Irish Green Street Management Company Limited | Households | 2004 |
| Irish Pharma Trading Ltd | Wholesale & retail | 2026 |
| Irsko Limited | Wholesale & retail | 2019 |
| Itell Holdings Ltd | Financial services | 2021 |
| Itell Properties Ltd | Real estate | 2019 |
| IVY Mead Management Limited | Extraterritorial | 2000 |
| Iwsf Limited | Wholesale & retail | 2024 |
| J and N Services Limited | Construction | 2015 |
| J D Meats Limited | Wholesale & retail | 2023 |
| J G Smith Limited | Health & social care | 2015 |