| FORM13 Limited | Professional & scientific | 2023 |
| Formae Pilates Ltd | Arts & recreation | 2026 |
| Formation Genie Ltd | Professional & scientific | 2016 |
| Fort Engineering Ltd | Manufacturing | 2014 |
| Fortain Limited | Information & communication | 2022 |
| Forte Developments Limited | Construction | 2001 |
| Forte Management Services Limited | Real estate | 2005 |
| Fortes Driveways Ltd | Construction | 2026 |
| Fortes Home Improvements Ltd | Construction | 2024 |
| Fortifoods Limited | Manufacturing | 2023 |
| Fortify Investment Properties Limited | Real estate | 2024 |
| Fortis Neveah Ltd. | Professional & scientific | 2017 |
| Fortis Security Services Ltd | Administrative & support | 2023 |
| Fortitude Electrical Ltd | Construction | 2025 |
| Fortnum Property Management Ltd | Construction | 2023 |
| Forttom Trading LLP | | 2026 |
| Fortum Limited | Professional & scientific | 2021 |
| Fortune Agape Impex Ltd | Wholesale & retail | 2019 |
| Fortune Tide Limited | Manufacturing | 2017 |
| Fortune's House Ltd | Hospitality | 2025 |
| Forvivo Associates Limited | Professional & scientific | 2013 |
| Forward Stream Ltd | Wholesale & retail | 2024 |
| FOS Consulting Ltd | Professional & scientific | 2025 |
| Foss Investment Properties Limited | Real estate | 2024 |
| Foster Reeves Ltd | Professional & scientific | 2025 |
| Foster’S Pest Control Ltd | Administrative & support | 2026 |
| Foundations Masters in Block Paving Limited | Construction | 2014 |
| Foundry HR Ltd | Administrative & support | 2026 |
| Four Core Global Limited | Information & communication | 2026 |
| Four Group of Trading Limited | Manufacturing | 2025 |
| Four Square PVT Limited | Information & communication | 2025 |
| Four Wheel Limited | Wholesale & retail | 2025 |
| Fouracres Consulting Limited | Professional & scientific | 2024 |
| Fourfields Management Company Limited | Real estate | 2024 |
| Fourmo Ltd | Wholesale & retail | 2020 |
| Fourteen Meridian Ltd | Other services | 2026 |
| Fourth Tier Ltd | Information & communication | 2023 |
| Fourtify Investments Limited | Real estate | 2025 |
| Fourtyfour Investment Limited | Real estate | 2026 |
| Fourways Accident Repair Centre Ltd | Wholesale & retail | 2020 |
| Fowler Homes Limited | Construction | 2003 |
| FOX Farriers Limited | Agriculture & fishing | 2017 |
| Fox-Shp Limited | Manufacturing | 2025 |
| Foxfield Wines Ltd | Wholesale & retail | 2006 |
| Foxforth Healthcare Limited | Health & social care | 2017 |
| Foxhall Homes Ltd | Construction | 2017 |
| Foxkash Limited | Professional & scientific | 2017 |
| Foxkloud Limited | Extraterritorial | 2017 |
| Foxley Kingham Limited | Professional & scientific | 1993 |
| Foxley Kingham Medical LLP | | 2008 |
| Foxmeister+ Ltd | Construction | 2026 |
| Foxmere Limited | Real estate | 2025 |
| Foys Forks Ltd | Construction | 2024 |
| Fozi Ltd | Wholesale & retail | 2020 |
| FPF Group Limited | Professional & scientific | 2022 |
| FPM Facility Services Limited | Construction | 2002 |
| Fpma Car Servicing Ltd | Wholesale & retail | 2019 |
| FQ Luton Limited | Information & communication | 2022 |
| FR Network Solutions Ltd | Information & communication | 2019 |
| FR Pharmaceutical Limited | Professional & scientific | 2024 |
| FR Solutions Ltd | Wholesale & retail | 2025 |
| Fragrina Ltd | Wholesale & retail | 2024 |
| Fram Logistics Ltd | Transport & logistics | 2026 |
| Fran Griffin PR Ltd | Professional & scientific | 2020 |
| Franalle Ltd | Hospitality | 2023 |
| Franchise Healthcare Ltd | Health & social care | 2022 |
| Francois Jacque Philipe Ltd | Households | 2024 |
| Frank Estates Limited | Real estate | 2025 |
| Frankie & Fries Limited | Hospitality | 2019 |
| Frankie Teddy Limited | Construction | 2024 |
| Fransic Ltd | Wholesale & retail | 2025 |
| Fratelli Spedition Ltd | Construction | 2021 |
| Fraz Motors Limited | Wholesale & retail | 2020 |
| Freddie Ellisdon Ltd | Administrative & support | 2019 |
| Frederick Charles Ltd | Construction | 2023 |
| Fredrack Enterprises Limited | Manufacturing | 2025 |
| Free Boiler Upgrade Ltd | Construction | 2023 |
| Freearch Limited | Construction | 2024 |
| Freecade Limited | Construction | 2024 |
| Freedom Epos Limited | Manufacturing | 1998 |
| Freedom Properties Liberta Limited | Real estate | 2024 |
| Freehold Holding Ltd | Financial services | 2026 |
| Freelance Films Ltd | Information & communication | 2012 |
| Freelance Hairdressers' Association | Other services | 2014 |
| Freeland Investments Ltd | Real estate | 2004 |
| Freeland Property Investments Ltd | Real estate | 2024 |
| Freeman & Hook Bricklaying Contractors Limited | Construction | 1997 |
| Freeman & Hook Contractors Ltd | Extraterritorial | 2011 |
| Freeman Agencies Limited | Wholesale & retail | 2003 |
| Freeman and Hook Scaffolding Limited | Construction | 2023 |
| Freeman House Management Company Limited | Households | 2024 |
| Freeze Dried Sweets Limited | Wholesale & retail | 2021 |
| Freight Direct Solutions Ltd | Transport & logistics | 2021 |
| Freightops Ltd | Transport & logistics | 2025 |
| Fresh 'N' Flavourful Ltd | Hospitality | 2025 |
| Fresh Air Testing UK Ltd | Professional & scientific | 2024 |
| Fresh and Start Luton Ltd | Hospitality | 2022 |
| Fresh Fruit and VEG Limited | Manufacturing | 2019 |
| Fresh Grill Bites Limited | Hospitality | 2026 |
| Fresh Ideas (UK) Ltd | Professional & scientific | 2012 |