| Floor Champions Ltd | Administrative & support | 2024 |
| Flooring Designs UK Limited | Construction | 2023 |
| Floorlux Limited | Construction | 2018 |
| Floors Carpets & Flooring Ltd | Construction | 2024 |
| Floreatrans Ltd | Transport & logistics | 2015 |
| Florentine Group Ltd | Wholesale & retail | 2024 |
| Florin Trans Logistics Ltd | Transport & logistics | 2019 |
| Florinboboc Ltd | Transport & logistics | 2025 |
| Flow Electrical Limited | Construction | 2008 |
| Flow Matic Installations Ltd | Construction | 2026 |
| Flowerminster Limited | Real estate | 1971 |
| Flowhero Emergency Services Ltd | Construction | 2026 |
| Flowline Commissioning Solutions Ltd | Administrative & support | 2026 |
| Flowtech Solutions Limited | Wholesale & retail | 2017 |
| FLY & Buy Ltd | Wholesale & retail | 2023 |
| Flyght Ltd | Administrative & support | 2016 |
| Flying Cabs Basildon Ltd | Transport & logistics | 2018 |
| Flynn & Whitfield Ltd | Transport & logistics | 2025 |
| FM Care Services Ltd | Health & social care | 2025 |
| FM Construction & Land Consultants Limited | Real estate | 2020 |
| Fm&E Services Ltd | Manufacturing | 2017 |
| Fmeg Ltd | Transport & logistics | 2023 |
| FO Global Ltd | Administrative & support | 2026 |
| Foakes Building Limited | Construction | 2018 |
| Foam Experts Ltd | Manufacturing | 2022 |
| Fobbing Electrical Limited | Construction | 2020 |
| Focus BMC Limited | Administrative & support | 2016 |
| Focus Media UK Limited | Professional & scientific | 2003 |
| Foley Amento Ltd | Health & social care | 2014 |
| Fona Godema Limited | Administrative & support | 2019 |
| Fonuoha Ltd | Public administration | 2021 |
| Foodpak Limited | Extraterritorial | 2013 |
| Football FUN Factory (Community 032) Limited | Arts & recreation | 2021 |
| Football FUN Factory (Community 086) Limited | Arts & recreation | 2023 |
| Footcare Services (Basildon) Limited | Health & social care | 2009 |
| Footy Cubes Ltd | Wholesale & retail | 2024 |
| FOR Four Paws Ltd | Wholesale & retail | 2021 |
| FOR Goodness Sheikh Ltd | Health & social care | 2021 |
| FOR the Record Ibiza Limited | Information & communication | 2023 |
| Forbes Power Tech Limited | Construction | 2025 |
| Ford Technologies Limited | Professional & scientific | 2003 |
| Forensic Healthcare Services Limited | Health & social care | 1999 |
| Forensis Consulting Limited | Professional & scientific | 2013 |
| Fores Building Ltd | Construction | 2026 |
| Forest Biotec Ltd | Professional & scientific | 2024 |
| Forest Gate Construction Co. Limited | Construction | 1948 |
| Forest Gate Construction EOT Limited | Administrative & support | 2023 |
| Forest Properties and Land Limited | Real estate | 2019 |
| Forge Welding Solutions Ltd | Manufacturing | 2026 |
| FORMA1 Construction Ltd | Administrative & support | 2023 |
| Formanz Ltd | Construction | 2017 |
| Forminte Construction Ltd | Construction | 2022 |
| Formosan Farms Limited | Wholesale & retail | 2020 |
| Forpostsolution Ltd | Wholesale & retail | 2019 |
| Forsite Design Group Ltd | Information & communication | 2022 |
| Fort Myers Holdings Limited | Financial services | 2024 |
| Fortflow Nexus Ltd | Health & social care | 2023 |
| Fortis Roofing & Building Ltd | Construction | 2026 |
| Fortitude Healthcare Services Ltd | Administrative & support | 2022 |
| Fortune and Wigan Limited | Professional & scientific | 2009 |
| Fosse Contractors Limited | Construction | 2022 |
| Fotuz UK Limited | Information & communication | 2010 |
| Four Leaf Recruitment Ltd | Administrative & support | 2025 |
| Four Seasons Roofing Building Ltd | Construction | 2023 |
| Four Technical Solutions Limited | Construction | 2017 |
| Fourteen Twelve Investments Ltd | Real estate | 2020 |
| Fourth Dimension Comms Limited | Construction | 2018 |
| Foxclothes Ltd | Wholesale & retail | 2026 |
| Foxclothesltd Limited | Wholesale & retail | 2026 |
| Foxco Global Ltd | Arts & recreation | 2024 |
| Foxx Property Solutions Limited | Households | 2024 |
| FPC Developments Ltd | Manufacturing | 2026 |
| FPR (UK) Limited | Professional & scientific | 2012 |
| FRA Smart Accounts Ltd | Professional & scientific | 2026 |
| Franek Projects Ltd | Construction | 2023 |
| Frankonell Limited | Information & communication | 2012 |
| Frankston (UK) Limited | Real estate | 2006 |
| Frankston Four Limited | Real estate | 2016 |
| Frasersimpson Reclamation & Antique Salvage Ltd | Other services | 2026 |
| Freedmans (Balers) Ltd | Wholesale & retail | 2012 |
| Freedom IS Life Ltd | Wholesale & retail | 2022 |
| Freedom Later Life Ltd | Financial services | 2021 |
| Freedom Logistics International Limited | Transport & logistics | 2002 |
| Freemans Farm Produce Limited | Wholesale & retail | 2007 |
| Freight Flow Services Ltd | Transport & logistics | 2026 |
| Freight Securing Systems Ltd | Manufacturing | 2001 |
| Freight Services T/A Cargo Company Ltd | Transport & logistics | 2019 |
| Frella Estates Ltd | Real estate | 2018 |
| Frella Services Ltd | Administrative & support | 2018 |
| Fresh Electrical Solutions Ltd | Construction | 2016 |
| Fresh Tree Care Services Limited | Public administration | 2019 |
| Freshcleaningnest Ltd | Administrative & support | 2026 |
| Freshworks Homes Ltd | Real estate | 2019 |
| Friary NO.6 PLC | Administrative & support | 2019 |
| FRS Mechanical Ltd | Construction | 2025 |
| Fruit for the Office Ltd | Wholesale & retail | 2007 |
| FS15 Limited | Professional & scientific | 2024 |
| FSJ Interiors Ltd | Construction | 2020 |
| FSM Services Ltd | Construction | 2023 |
| Fsperring Transport Limited | Transport & logistics | 2026 |