| Fncd Murphy Engineering Limited | Construction | 2018 |
| Focus Cafe Ltd | Hospitality | 2026 |
| Focused Contracts Ltd | Construction | 2025 |
| Fogo (NI) Limited | Manufacturing | 2012 |
| Fomhar NA Mara Limited | Agriculture & fishing | 2014 |
| FON Contracts Ltd | Construction | 2021 |
| Food-Bridge (NI) Ltd | Wholesale & retail | 2020 |
| Food-Bridge UK Limited | Wholesale & retail | 2012 |
| FOR the Click Ltd | Arts & recreation | 2025 |
| Force Equipment Limited | Manufacturing | 2005 |
| Forde Property Management Ltd | Real estate | 2023 |
| Fords Cross Transport Ltd | Transport & logistics | 2023 |
| Foresight Creative Ltd | Professional & scientific | 2021 |
| Forest Hills Developments Ltd | Construction | 2020 |
| Forest Hills Investments Limited | Real estate | 2025 |
| Forest Hills Management Company Ltd | Households | 2020 |
| Forestbrook Enterprises Ltd | Agriculture & fishing | 2026 |
| Forestry Improvement Services Limited | Agriculture & fishing | 2014 |
| Forestwood Trading Limited | Real estate | 1977 |
| Forever Furniture Ltd | Extraterritorial | 2021 |
| Forevvr Ironing Ltd | Administrative & support | 2019 |
| Fork Rentals Ltd | Real estate | 2020 |
| Forkhill Cattle Company Ltd | Agriculture & fishing | 2015 |
| Forkhill Preschool Playgroup Ltd | Education | 2019 |
| Forkhill Road Services Ltd | Wholesale & retail | 2014 |
| Forkhill Van & Car Sales Limited | Wholesale & retail | 2011 |
| Forsythe Consulting Ltd | Professional & scientific | 2016 |
| Forsythe House Ltd | Professional & scientific | 2019 |
| Fort Evergreen Limited | Arts & recreation | 2013 |
| Fortis Protection & Risk Management Limited | Administrative & support | 2026 |
| Fortwilliam and Ballymena Specialist Dental Clinics Limited | Health & social care | 2010 |
| Forway Business L.P. | | 2017 |
| Foster Bros Ltd | Administrative & support | 2005 |
| Foughill Property Ltd | Real estate | 2024 |
| Foundary Court Ltd | Households | 2005 |
| Founding Four Ltd | Financial services | 2025 |
| Fourmile Holdings Ltd | Manufacturing | 2024 |
| FOX Bricklaying Ltd | Construction | 2024 |
| FOX Groundworks Limited | Construction | 2016 |
| FOX PUB Ltd | Hospitality | 2019 |
| Foxfield Construction and Plant Ltd | Construction | 2017 |
| Foxfield Engineering Limited | Manufacturing | 2016 |
| Foxfield Livestock Limited | Agriculture & fishing | 2023 |
| Foxwell Trade L.P. | | 2017 |
| FPM Bricklaying Ltd | Construction | 2025 |
| FR Estate Properties Ltd | Real estate | 2015 |
| Frabar Ltd | Real estate | 2024 |
| Framework Safety Group Ltd | Professional & scientific | 2024 |
| Francis Court Limited | Hospitality | 2015 |
| Francis Street Service Station Limited | Wholesale & retail | 2010 |
| Francoway Associates L.P. | | 2015 |
| Frank Safety Ltd | Information & communication | 2019 |
| Frankham (IRE) Ltd | Real estate | 2019 |
| Frankham Group Ltd | Financial services | 2020 |
| Franklin Communications L.P. | | 2017 |
| Franks Electrical Ltd | Construction | 2025 |
| Frass Limited | Real estate | 2020 |
| Frazer Haulage Limited | Transport & logistics | 2013 |
| Frazer Poultry Limited | Agriculture & fishing | 2021 |
| Freedom Cosmetics Ltd | Wholesale & retail | 2020 |
| Freedoms Enterprises Limited | Arts & recreation | 2023 |
| Freeduff Close Management Company Limited | Households | 2023 |
| Freeduff Property Rental Ltd | Real estate | 2017 |
| Freefalcon UK & Ireland Limited | Wholesale & retail | 2017 |
| Freeflowfinance Ltd | Professional & scientific | 2025 |
| Freshol Ltd | Wholesale & retail | 2025 |
| Friends of Tyrone Limited | Arts & recreation | 2024 |
| Friskotland LP | | 2014 |
| Fromnorthtwosouth Ltd | Information & communication | 2024 |
| Frontier BUS Hire Ltd | Transport & logistics | 2019 |
| Frozen Ground Ltd | Hospitality | 2026 |
| FRS Employability Limited | Administrative & support | 2021 |
| FSH Capital Limited | Manufacturing | 2025 |
| Fskpt Ltd | Other services | 2015 |
| Fuel Trans Ltd | Wholesale & retail | 2009 |
| Full Stack Cloud Services Ltd | Information & communication | 2021 |
| Fulla Beans Ltd | Hospitality | 2018 |
| Funcom UK Ltd | Information & communication | 2024 |
| Funk Soul Media CIC | Information & communication | 2022 |
| Funky Monkeys Playcentres Ltd | Administrative & support | 2010 |
| Funky Monkeys Softplay Dundonald Ltd | Hospitality | 2014 |
| Funky Monkeys Softplay Newport Ltd | Hospitality | 2013 |
| Funky Monkeys Softplay West Brom Ltd | Hospitality | 2014 |
| Funtasia Funfairs Limited | Arts & recreation | 2000 |
| Furnco Limited | Real estate | 2015 |
| Furniture IS US Limited | Wholesale & retail | 2012 |
| Further Ventures Ltd | Wholesale & retail | 2023 |
| Futurag Limited | Wholesale & retail | 2020 |
| Future Classic Cars Ltd | Wholesale & retail | 2025 |
| Futurecore Engineering Ltd | Construction | 2025 |
| FW Services Ltd | Wholesale & retail | 2015 |
| FÁS Business Solutions Limited | Professional & scientific | 2017 |
| G & a Hospitality Services Ltd | Administrative & support | 2020 |
| G & D Kitchens Limited | Construction | 2008 |
| G & P Corp. LP | | 2016 |
| G & P Diamonds LP | | 2016 |
| G & P Industrial LP | | 2016 |
| G & P OIL LP | | 2016 |
| G C R Contracts Ltd | | 2005 |
| G F Roofing Ltd | Construction | 2015 |