| Formamarjen Ltd | Wholesale & retail | 2023 |
| Formans Mechanics Limited | Wholesale & retail | 2026 |
| Format Architects Ltd | Professional & scientific | 2019 |
| Format Factory Ltd | Information & communication | 2004 |
| Formby Sushi Limited | Hospitality | 2025 |
| Formel D (UK) Limited | Information & communication | 1994 |
| Formidability | Arts & recreation | 2019 |
| Formilly CIC | Information & communication | 2025 |
| Formiti Data International UK Ltd | Professional & scientific | 2021 |
| Formosa Construction LLP | | 2015 |
| Forpaul Limited | Wholesale & retail | 2015 |
| Forrentech Ltd | Wholesale & retail | 2025 |
| Forrest Fotos Limited | Professional & scientific | 2015 |
| Forrest Tools Ltd | Manufacturing | 2017 |
| Forrester Insight Services Limited | Professional & scientific | 2022 |
| Forrester Ketley Limited | Professional & scientific | 2001 |
| Forresters IP LLP | | 2017 |
| Forresters IP Renewals LLP | | 2020 |
| Forster Profile Systems (UK) Ltd | Wholesale & retail | 2015 |
| Forsvarir Software Ltd | Information & communication | 2022 |
| Fort Advocacy Limited | Health & social care | 2018 |
| Fort Care and Support Limited | Health & social care | 2025 |
| Fort Consultancy Ltd | Professional & scientific | 2019 |
| Fort Housing and Support Ltd | Hospitality | 2025 |
| Fort Knox Fabrications Ltd | Professional & scientific | 2015 |
| Fort Parking Solutions Ltd | Transport & logistics | 2021 |
| Fort Paull Leisure Limited | Real estate | 2020 |
| Fort Property Developments Limited | Real estate | 2018 |
| Fort Selfstorage Ltd | Transport & logistics | 2006 |
| Forte Care Ltd | Health & social care | 2020 |
| Fortek Stone Ltd | Wholesale & retail | 2025 |
| Fortescue Beauty Limited | Wholesale & retail | 2016 |
| Forth Together CIC | Information & communication | 2021 |
| Fortico Security Solutions Ltd | Administrative & support | 2024 |
| Fortify Construction Group Ltd | Construction | 2025 |
| Fortil UK Ltd | Administrative & support | 2015 |
| Fortis Build Group Limited | Construction | 2025 |
| Fortis Guard Security Ltd | Administrative & support | 2024 |
| Fortis Horizons Limited | Financial services | 2020 |
| Fortis Housing Ltd | Construction | 2023 |
| Fortis Investments Management Limited | Financial services | 2018 |
| Fortis Motor Group Ltd | Wholesale & retail | 2025 |
| Fortis Pro Cleanerz Ltd | Administrative & support | 2026 |
| Fortis Property Group Limited | Construction | 2017 |
| Fortis Secure Ltd | Transport & logistics | 2025 |
| Fortis Stylo Ltd | Professional & scientific | 2026 |
| Fortisec Limited | Administrative & support | 2025 |
| Fortitude Education Ltd | Education | 2024 |
| Fortitude Energy Ltd | Wholesale & retail | 2026 |
| Fortmire Limited | Real estate | 2021 |
| Fortnum Family Office Limited | Professional & scientific | 2018 |
| Fortoak Rolls Limited | Wholesale & retail | 2005 |
| Fortrader Ltd | Wholesale & retail | 2016 |
| Fortran Solution Ltd | Information & communication | 2022 |
| Fortress & Knight Ltd | Education | 2019 |
| Fortress Cyber Security Ltd | Information & communication | 2026 |
| Fortress Facilities and Security Ltd | Administrative & support | 2025 |
| Fortress Locksmiths Limited | Other services | 2004 |
| Fortress Safety Solutions Ltd | Construction | 2026 |
| Forts Properties Limited | Real estate | 2023 |
| Fortserve Limited | Wholesale & retail | 2026 |
| Fortuna Spring Investment Ltd | Real estate | 2020 |
| Fortunate Integrated Services Limited | Transport & logistics | 2025 |
| Fortune 88 Limited | Hospitality | 2022 |
| Fortune Cat Limited | Real estate | 2022 |
| Fortune Club Limited | Hospitality | 2023 |
| Fortune Entertainment Ltd | Hospitality | 2019 |
| Fortune House (Kings Norton) Ltd | Hospitality | 2019 |
| Fortune Mart Ltd | Wholesale & retail | 2026 |
| Fortune NP Limited | Real estate | 2022 |
| Fortune Rendezvous Limited | Hospitality | 2026 |
| Fortune Skyline Ltd | Hospitality | 2023 |
| Fortune Solutions Limited | Wholesale & retail | 2023 |
| Fortune UK Property Investment Limited | Real estate | 2021 |
| Fortune Wise Limited | Administrative & support | 2024 |
| Forty Two Housing Ltd | Households | 2025 |
| Fortysevencapital Ltd | Real estate | 2026 |
| Forum for Independent Psychotherapists | Health & social care | 2010 |
| Forum IQ Limited | Professional & scientific | 2024 |
| Forum Underwriting Limited | Professional & scientific | 1996 |
| Forward Carers C.I.C. | Health & social care | 2015 |
| Forward Computers Alliance Limited | Information & communication | 2024 |
| Forward Computers Limited | Information & communication | 1996 |
| Forward Contracts Ltd | Construction | 2021 |
| Forward Double Glazing Ltd | Construction | 2021 |
| Forward Drains Limited | Water & waste | 1985 |
| Forward Education Trust | Education | 2017 |
| Forward Engineering Solutions Limited | Construction | 2014 |
| Forward Fastener Manufacturing Limited | Manufacturing | 1999 |
| Forward First Limited | Other services | 2016 |
| Forward Focus Courier Services Ltd | Transport & logistics | 2024 |
| Forward Focused Properties Ltd | Real estate | 2025 |
| Forward Football CIC | Arts & recreation | 2025 |
| Forward for Life Limited | Professional & scientific | 2012 |
| Forward Gallery Ltd | Arts & recreation | 2011 |
| Forward Health Solutions Limited | Health & social care | 2020 |
| Forward Hire Ltd | Administrative & support | 2024 |
| Forward Housing | Real estate | 1999 |
| Forward Nominees Limited | Extraterritorial | 2005 |
| Forward Partnership Limited | Education | 2008 |