| Forma Labs Audio Ltd | Information & communication | 2026 |
| Formak Estudio Ltd | Professional & scientific | 2025 |
| Formexo Tools Limited | Information & communication | 2026 |
| Formpro Ltd | Construction | 2023 |
| Fornham Limited | Transport & logistics | 2024 |
| Forsite Banners Ltd | Professional & scientific | 2023 |
| Fortapura Limited | Information & communication | 2025 |
| Fortay Limited | Administrative & support | 2016 |
| Fortes Estates Ltd | Construction | 2020 |
| Fortis Investments Ltd | Real estate | 2007 |
| Fortis Stays Limited | Hospitality | 2026 |
| Fortis Stone Ltd | Information & communication | 2020 |
| Fortress Landscaping Ltd | Administrative & support | 2026 |
| Fortune Draw Ltd | Arts & recreation | 2025 |
| Fortune Fightwear Ltd. | Wholesale & retail | 2024 |
| Forty-Three Chepstow Road Limited | Households | 1985 |
| Forwardmx Limited | Information & communication | 2025 |
| Fossgate Ltd | Information & communication | 2025 |
| Fossgate Management Limited | Real estate | 2006 |
| Fosterdown Limited | Financial services | 2023 |
| Fostering Voices Ltd | Education | 2026 |
| Fotelive Properties Limited | Real estate | 2025 |
| Founder 2 Closer Ltd | Professional & scientific | 2025 |
| Foundry Digi Ltd | Professional & scientific | 2026 |
| Foundry Place Properties Limited | Real estate | 2013 |
| Four Bishops Management Ltd | Households | 2015 |
| Four Cherubim Care Ltd | Administrative & support | 2023 |
| Four on the Floor Ltd | Wholesale & retail | 2026 |
| Four Rent Living Ltd | Real estate | 2025 |
| Fourcefield Ltd | Professional & scientific | 2025 |
| Fourcorners Property Services Ltd | Real estate | 2024 |
| Fourpaws Pampering Ltd | Other services | 2024 |
| Fourth Rock Publishing Ltd | Information & communication | 2021 |
| Fourth Wall Padel Ltd | Arts & recreation | 2025 |
| Fovea Analytics Limited | Information & communication | 2024 |
| FOX and FOX Electrics Ltd | Manufacturing | 2020 |
| FOX Connect Ltd | Information & communication | 2019 |
| FOX Landscape Gardening Limited | Administrative & support | 2016 |
| FOX Lane Music Limited | Information & communication | 2018 |
| Foxglove Nurseries Ltd | Health & social care | 2020 |
| Foxhill Group Holding Limited | Financial services | 2026 |
| Foxhole Technology Solutions Ltd | Information & communication | 2023 |
| Foxlion Ltd | Real estate | 2026 |
| Foxred Investments Ltd | Real estate | 2019 |
| Foxy Cars Private Hire Services Ltd | Other services | 2017 |
| Foyer Recruitment Ltd | Administrative & support | 2026 |
| FP Associates and Consultants Limited | Manufacturing | 2017 |
| FP Maghery Civils Ltd | Construction | 2026 |
| Fractal Logic Ltd | Professional & scientific | 2025 |
| Fraction Consultants LLP | | 2019 |
| Fractional Force Ltd | Professional & scientific | 2024 |
| Fractular Limited | Professional & scientific | 2024 |
| Fragranze Apps Limited | Information & communication | 2012 |
| Frame & Fluff Co Ltd | Wholesale & retail | 2023 |
| Frame Vision Group Ltd | Wholesale & retail | 2026 |
| Framezap Limited | Wholesale & retail | 2025 |
| Francela Fine Dining Limited | Hospitality | 2025 |
| Franchise Freedom Systems Ltd | Administrative & support | 2026 |
| Francis Property Holdings Ltd | Real estate | 2025 |
| Frank Lane Picture Agency Limited | Other services | 1984 |
| Frankies Fishing Tackle Ltd | Wholesale & retail | 2014 |
| FRC Cleaning Services Ltd | Administrative & support | 2023 |
| Freckenham Secure Dog Field Limited | Other services | 2024 |
| Frederick J French Limited | Construction | 2016 |
| Free Czechoslovak Air Force Associates Ltd | Information & communication | 2010 |
| Free Knowledge Africa CIC | Education | 2025 |
| Free Range Campers Holdings Ltd | Wholesale & retail | 2025 |
| Free Range Campers Ltd | Administrative & support | 2021 |
| Free-Spirit Records Ltd | Transport & logistics | 2008 |
| Freeacre Limited | Real estate | 2011 |
| Freedom Bars Suffolk Ltd | Administrative & support | 2025 |
| Freedom Taxis Harrogate Ltd | Transport & logistics | 2017 |
| Freeman Music Group Limited | Arts & recreation | 2015 |
| Freerange Lamas Ltd | Information & communication | 2025 |
| Freesbee Ltd | Arts & recreation | 2026 |
| Freestone Assets Limited | Real estate | 2022 |
| Freight Compare Group Limited | Transport & logistics | 2026 |
| Freightaway Ltd | Transport & logistics | 2025 |
| Frellex Ltd | Information & communication | 2025 |
| Frequency Music Group Limited | Information & communication | 2025 |
| Fresh Ideals Community Interest Company | Other services | 2006 |
| Fresh Look Films Ltd | Information & communication | 2014 |
| Fresh Meat Fayre Limited | Manufacturing | 2006 |
| Fresh Plastics UK Limited | Wholesale & retail | 2013 |
| Fresh Start Cleaning Ltd | Administrative & support | 2020 |
| Fresh Start Cleans (Bury St.Edmunds) Ltd | Administrative & support | 2025 |
| Fresher Juice Ltd | Manufacturing | 2024 |
| Freshline Solutions Limited | Administrative & support | 2025 |
| Freshly Brewed Property Ltd | Real estate | 2017 |
| Freshly Brewed Software Limited | Information & communication | 2014 |
| Freshnary Ltd | Manufacturing | 2023 |
| Freshties Limited | Health & social care | 2004 |
| Freshxchange Limited | Wholesale & retail | 2025 |
| Frexexpress Ltd | Wholesale & retail | 2023 |
| Freybellina & Gibbs Ltd | Professional & scientific | 2023 |
| Friendly Tools Ltd | Information & communication | 2026 |
| Friends of West Special School | Education | 2015 |
| Fries Food Limited | Wholesale & retail | 2025 |
| Friskeys Limited | Hospitality | 2019 |
| FRM Technology Limited | Information & communication | 2021 |