| Fairest & Pierce Ltd | Real estate | 2023 |
| Fairfields Glen Management Company Ltd | Administrative & support | 2015 |
| Fairhaven Residential Homes Limited | Health & social care | 1998 |
| Fairhead Rentals Ltd | Real estate | 2022 |
| Fairies Don’T Exist Ltd | Information & communication | 2024 |
| Fairjax Enterprises Limited | Real estate | 1993 |
| Fairmont Apartments Management Limited | Real estate | 2026 |
| Fairview Farm Road 2 Management Co Ltd | Real estate | 2026 |
| Fairview Farm Road Management Company Limited | Real estate | 2017 |
| Fairview Inventories (NI) Ltd | Real estate | 2013 |
| Fairways AMC Limited | Households | 1999 |
| Fairways Care Holdings Limited | Financial services | 2025 |
| Fairways Cushendall Management Limited | Extraterritorial | 2001 |
| Fairways Developments (NI) Limited | Real estate | 2006 |
| Fairways NI Limited | Arts & recreation | 2006 |
| Fairy Luolou Co., Ltd | Wholesale & retail | 2024 |
| Fairylane Limited | Professional & scientific | 2026 |
| Fairylane Properties Limited | Health & social care | 2014 |
| Faizan Flow Ltd | Wholesale & retail | 2025 |
| Faizan Zoom Ltd | Wholesale & retail | 2025 |
| Faizymart Ltd | Wholesale & retail | 2024 |
| Falafel Belfast Ltd | Hospitality | 2025 |
| Falaville Ltd | Hospitality | 2025 |
| Falcon Glober Ltd | Information & communication | 2019 |
| Falls Community Council Limited | Public administration | 2001 |
| Falls Language Hub CIC | Education | 2026 |
| Falls Road Butcher Limited | Wholesale & retail | 2025 |
| Falls Road Supermarket Ltd | Wholesale & retail | 2025 |
| False Victories Ltd | Information & communication | 2023 |
| Falsies Limited | Wholesale & retail | 2025 |
| Fama Products Ltd | Wholesale & retail | 2025 |
| Fame Food Ltd | Hospitality | 2025 |
| Family Care Adoption Services | Professional & scientific | 1989 |
| Family Court Support Ltd | Professional & scientific | 2012 |
| Family Forte Limited | Hospitality | 2025 |
| Family Routes | Health & social care | 1990 |
| Family Toolbox CIC | Health & social care | 2015 |
| Fancy Goods Studios Ltd | Information & communication | 2020 |
| Fanda Network Limited | Other services | 2024 |
| Fandangle Films Ltd | Information & communication | 2025 |
| Fanfán Ltd | Information & communication | 2020 |
| Fang Zhou Ltd | Wholesale & retail | 2023 |
| Fangbin Trade Limited | Wholesale & retail | 2024 |
| Fangbing Zhou Ltd | Wholesale & retail | 2023 |
| Fangrun Ltd | Wholesale & retail | 2024 |
| Fanjaho Ltd | Wholesale & retail | 2025 |
| Fanshopjon Ltd | Wholesale & retail | 2023 |
| Faonon Limited | Wholesale & retail | 2024 |
| FAR East Shop Limited | Wholesale & retail | 2023 |
| Farevale Developments Limited | Construction | 2006 |
| Farg Holdings Limited | Real estate | 2026 |
| Farhan Associates Limited | Real estate | 2023 |
| Faribo Ltd | Wholesale & retail | 2020 |
| Fariss Holdings Ltd | Financial services | 2024 |
| Fariss Ltd | Other services | 2017 |
| Farleigh (NI) Limited | Construction | 2023 |
| Farley Davison & Associates Limited | Professional & scientific | 1991 |
| Farm Lodge Lane 2015 Limited | Households | 2015 |
| Farm Week Ltd | Information & communication | 2006 |
| Farmako Consulting Ltd | Professional & scientific | 2019 |
| Farmhill Wind Ltd | Energy | 2017 |
| Farmlea Foods Ltd | Extraterritorial | 1982 |
| Farmley Housing Ltd | Real estate | 2016 |
| Farmmax Ltd | Professional & scientific | 2020 |
| Farr Removed Limited | Transport & logistics | 2021 |
| Farrans (Construction) Limited | Extraterritorial | 1943 |
| Farrans Limited | Construction | 1958 |
| Farrell Construction N.I. Ltd | Construction | 2025 |
| Farrell Property Rentals NI Ltd | Real estate | 2024 |
| Farrell Services N.I. Ltd | Construction | 2024 |
| Farrier & Cupar Healthcare Limited | Administrative & support | 2022 |
| Farrier Gate Management Company Ltd | Households | 2019 |
| Farset Labs | Education | 2012 |
| Farsighted Insights Ltd | Wholesale & retail | 2024 |
| Fashion Cloud Ltd | Wholesale & retail | 2025 |
| Fashu Gnahz Ltd | Wholesale & retail | 2024 |
| Fasoli Lian Ltd | Wholesale & retail | 2025 |
| Fast Oils Limited | Wholesale & retail | 2011 |
| Fast'N'Fresh Food Concepts Ltd | Hospitality | 2021 |
| Fastandtumorous Ltd | Wholesale & retail | 2025 |
| FASTVIEW360 Ireland Ltd | Information & communication | 2021 |
| FAT Panda Media Ltd | Information & communication | 2021 |
| Fathom Energy & Environment Ltd | Professional & scientific | 2011 |
| Fatlad Triathlon Series Ltd Ltd | Education | 2024 |
| Faultline Cyber & Security Ltd | Information & communication | 2026 |
| FAV Advisory Ltd | Other services | 2026 |
| Favourit Foods Ltd | Manufacturing | 1915 |
| FAY Frances Ltd | Wholesale & retail | 2023 |
| Fayers NI Property Investment Ltd | Real estate | 2026 |
| Fayore Ltd | Wholesale & retail | 2025 |
| Fazaza EAT Ltd | Information & communication | 2026 |
| Fazz Food Limited | Hospitality | 2020 |
| Fazzocado Ltd | Hospitality | 2025 |
| Fbaa Ltd | Wholesale & retail | 2021 |
| Fbgm Film Services Ltd | Information & communication | 2024 |
| FC Rigging Ltd | Construction | 2023 |
| FC Secretarial Services Limited | Extraterritorial | 2000 |
| FCC Construction Northern Ireland Limited | Construction | 2008 |
| Fcni Ltd | Administrative & support | 2019 |
| FCP Ni&Uk Ltd | Water & waste | 2026 |