| Findan Farming Ltd | Agriculture & fishing | 2016 |
| Finkey Limited | Real estate | 2016 |
| Finmac Ltd | Construction | 2025 |
| Finn Valley Project Management Ltd | Professional & scientific | 2019 |
| Fintona Autospares Ltd | Wholesale & retail | 2025 |
| Fintona Medical Hall Limited | Wholesale & retail | 2013 |
| Fintona Railway Homes Ltd | Real estate | 2024 |
| Fintona Tyre Service Ltd | Wholesale & retail | 2023 |
| Fionn Consulting Ltd | Water & waste | 2024 |
| Fioru Software Solutions UK Limited | Information & communication | 2018 |
| Fire & Feed Ltd | Hospitality | 2022 |
| First Geotechnics Limited | Professional & scientific | 2022 |
| Fixline Interiors Ltd | Construction | 2025 |
| FL Traders Ltd | Wholesale & retail | 2022 |
| Flexicommerce Holdings Ltd | Wholesale & retail | 2024 |
| Flood Marine Services Ltd | Wholesale & retail | 2021 |
| Floors Direct (NI) Ltd | Extraterritorial | 2005 |
| Flowfront Ltd | Information & communication | 2025 |
| Flushtown Farms Ltd | Agriculture & fishing | 2025 |
| Flynn Bros. Rent-A-Car Limited | Administrative & support | 1989 |
| Flynn Thomas Bespoke Ltd | Manufacturing | 2017 |
| FMC Accountants Limited | Professional & scientific | 2014 |
| FMC Electrical Services Ltd | Construction | 2007 |
| FMC Funeral Services Ltd | Other services | 2014 |
| Food Force (Ireland) Drinks Limited | Wholesale & retail | 2013 |
| Food Force (Ireland) Limited | Administrative & support | 1993 |
| Forged Innovation Limited | Manufacturing | 2019 |
| Form Builders Ltd | Manufacturing | 1999 |
| Formil Limited | Wholesale & retail | 2025 |
| Formil Plant Hire Limited | Construction | 2009 |
| Fort Research Limited | Information & communication | 2026 |
| Fortress Solutions Ireland Ltd | Administrative & support | 2025 |
| Fortyfivecollective Limited | Wholesale & retail | 2025 |
| FOX Agri Ltd | Extraterritorial | 2019 |
| FOX Dental Surgery | Health & social care | 2011 |
| FOX Law Limited | Professional & scientific | 2014 |
| FOX Quarries Limited | Construction | 2014 |
| Fox's Flooring Ltd | Construction | 2026 |
| Foyle Food Group Holdings Limited | Manufacturing | 2007 |
| Foyle Food Group Limited | Manufacturing | 1998 |
| Foyle Meats Limited | Manufacturing | 2017 |
| Foyle Proteins Limited | Manufacturing | 2017 |
| FPK Sales Limited | Wholesale & retail | 2013 |
| Fran Mcgirr & SON Limited | Wholesale & retail | 2005 |
| Frankie Cafe Ltd | Hospitality | 2022 |
| Fraser Homes Limited | Real estate | 1982 |
| Fred Mcdowell Ltd | Construction | 2006 |
| Friends of Loughmacrory C.I.C. | Administrative & support | 2023 |
| Frozen Beverage Services Ltd | Administrative & support | 2025 |
| Fuelstore Omagh Limited | Wholesale & retail | 2017 |
| Fyffe Contracts Ltd | Agriculture & fishing | 2018 |
| Fyfin Energy Ltd | Energy | 2017 |
| Fíor Contracts Ltd | Construction | 2018 |
| G & T Hamilton Ltd | Real estate | 2025 |
| G F Wilson Limited | Construction | 2014 |
| G MC Q Properties Ltd | Real estate | 2007 |
| G Mcbride Ltd | Construction | 2019 |
| G&G Vapes Ltd | Wholesale & retail | 2023 |
| G-Mac Power Packs Ltd | Manufacturing | 2015 |
| GA Adams Building Ltd | Construction | 2016 |
| GA Trailers Group Ltd | Manufacturing | 2026 |
| Gabe (UK) Ltd | Construction | 2009 |
| GAC Consultancy Services Ltd | Professional & scientific | 2022 |
| Gaelsure Limited | Financial services | 2024 |
| GAF Plant Hire Ltd | Construction | 2013 |
| Gairloch Resources Ltd | Mining & quarrying | 2023 |
| Gala Wind Ltd | Manufacturing | 2018 |
| Galaxy Facilities Management Ltd | Construction | 2008 |
| Galaxy Property Solutions Ltd | Real estate | 2013 |
| Galetech Energy (UK) Limited | Energy | 2015 |
| Galetech Energy Holdings (UK) Ltd | Energy | 2025 |
| Galetech Energy Services Ltd | Professional & scientific | 2019 |
| Galetech Operations UK Ltd | Manufacturing | 2026 |
| Gallagher Engineering Ltd | Construction | 2023 |
| Gallagher Hvac Europe Ltd | Construction | 2024 |
| Gallagher Livestock Ltd | Agriculture & fishing | 2022 |
| Gallagher Trading Ltd | Construction | 2020 |
| Gallaghers Car Sales (N.I.) Ltd | Wholesale & retail | 2021 |
| Gallco Ltd | Real estate | 2012 |
| Gallen Vehicle Hire Ltd | Wholesale & retail | 2003 |
| Gallmic Medical Ltd | Health & social care | 2024 |
| Gansher Ltd | Hospitality | 2016 |
| Gargrim Ltd | Administrative & support | 2017 |
| Garin Limited | Construction | 2024 |
| Garvaghullion Properties Limited | Construction | 2012 |
| Garvallagh Farms Ltd | Agriculture & fishing | 2019 |
| Garvallagh Investments Limited | Construction | 2021 |
| Garvallagh Properties Ltd | Real estate | 2026 |
| Garvoge Holdings Ltd | Financial services | 2023 |
| Gary Kavanagh Ltd | Agriculture & fishing | 2021 |
| GC 96 Ltd | Hospitality | 2022 |
| GC Properties Omagh Ltd | Real estate | 2025 |
| Gentle D Limited | Health & social care | 2025 |
| GEO Poultry Grit Ltd | Mining & quarrying | 2012 |
| George Gallagher Metals Ltd | Water & waste | 2004 |
| Gerard Mccourt Ltd | Construction | 2019 |
| GFS Omagh Limited | Wholesale & retail | 2017 |
| GHS Property Limited | Real estate | 2017 |
| Gibson Properties (N.I.) Ltd | Real estate | 2022 |
| GK Traditional Family Butchers Ltd | Manufacturing | 2013 |