| Fiodor Limited | Construction | 2025 |
| Fiori & Patio Ltd | Administrative & support | 2022 |
| Firmly Medical Ltd | Wholesale & retail | 2013 |
| First Alliance Services Ltd | Administrative & support | 2022 |
| First Choice Resources Ltd | Construction | 2017 |
| First Choice Traders Ltd | Construction | 2025 |
| First Class Education Solutions Limited | Administrative & support | 2016 |
| First Class Finance and Payroll Solutions Limited | Professional & scientific | 2014 |
| First Construct Group Ltd | Construction | 2019 |
| First Construction and Groundworks Limited | Construction | 2019 |
| First Construction Services Ltd | Real estate | 2022 |
| First Direct Training Ltd | Public administration | 2010 |
| First E-Principles Ltd | Information & communication | 2019 |
| First Hire Services Ltd | Transport & logistics | 2023 |
| First Journey Driving School Ltd | Education | 2025 |
| First Rate Tutors Academic Scholarships Limited | Education | 2026 |
| First Realty and Management Limited | Construction | 2025 |
| First Step to Healthcare Ltd | Health & social care | 2023 |
| Firstchoice Consultancy Ltd | Real estate | 2010 |
| Fiscal Edge Ltd | Professional & scientific | 2024 |
| Fishway Ltd | Wholesale & retail | 2020 |
| Fit BF Limited | Wholesale & retail | 2024 |
| Fit Motors Ltd | Wholesale & retail | 2026 |
| Fit Pro Flooring Ltd | Construction | 2022 |
| Fitness One Ltd | Other services | 2024 |
| Fitted Central Ltd | Wholesale & retail | 2025 |
| Fitthesunnah Ltd | Wholesale & retail | 2024 |
| Five Angel Care Limited | Health & social care | 2023 |
| Five Brothers Building Ltd | Construction | 2022 |
| Five Elms Drycleaners Ltd | Other services | 2024 |
| Five Fingers London Ltd | Hospitality | 2021 |
| Five Star Excel UK Ltd | Manufacturing | 2015 |
| FIX & Go Auto Ltd | Wholesale & retail | 2025 |
| FIX ALL Magic Ltd | Construction | 2015 |
| FIX and Go Building Ltd | Construction | 2025 |
| FIX Expert Limited | Wholesale & retail | 2025 |
| FIX IT Glazing Ltd | Manufacturing | 2025 |
| Fix&Build Construction Ltd | Construction | 2024 |
| Fixit Builder Limited | Construction | 2019 |
| Fixmasters Ltd | Construction | 2011 |
| Fixted Ltd | Construction | 2018 |
| FJ Landscaping & Groundworks Ltd | Construction | 2017 |
| FKM Group Ltd | Administrative & support | 2025 |
| Flame Grill Eatery Limited | Hospitality | 2024 |
| Flavors of Punjab Ltd | Hospitality | 2026 |
| Flavour Street Ltd | Hospitality | 2026 |
| Flawless Kare Ltd | Wholesale & retail | 2025 |
| Fled Building Construction Limited | Administrative & support | 2021 |
| Fleek Business Limited | Wholesale & retail | 2020 |
| Fleeto Ltd | Extraterritorial | 2015 |
| Flenjur Ltd. | Manufacturing | 2024 |
| Flex Autoline Ltd | Wholesale & retail | 2020 |
| Flex by Felicia Limited | Health & social care | 2023 |
| Flex Logistics Ltd | Transport & logistics | 2021 |
| Flexi Higher Study and Training Limited | Education | 2020 |
| Flexi HR and Compliance Limited | Professional & scientific | 2021 |
| Flexible Packagings Limited | Manufacturing | 1992 |
| Flexible Transport Ltd | Transport & logistics | 2024 |
| Flexicase Collective Ltd | Wholesale & retail | 2026 |
| Flexsam Care Limited | Health & social care | 2025 |
| Flick Media Consulting Ltd | Professional & scientific | 2022 |
| Flick Media Limited | Information & communication | 2008 |
| Float Enterprise Limited | Transport & logistics | 2025 |
| Flobyte Limited | Information & communication | 2025 |
| Floki Dryliner Ltd | Construction | 2020 |
| Flominence Consultancy Ltd | Information & communication | 2015 |
| Flores Trans Ltd | Transport & logistics | 2019 |
| Floresta Organics Ltd | Wholesale & retail | 2021 |
| Florin UK Production Ltd | Construction | 2023 |
| Flourish Construction Ltd | Manufacturing | 2020 |
| Flourish NJ Property Ltd | Real estate | 2024 |
| Flourish NJ UK Ltd | Administrative & support | 2017 |
| Flow Maintenance Ltd | Construction | 2025 |
| Flowreach Ltd | Professional & scientific | 2024 |
| FLR Construction Ltd | Construction | 2021 |
| Flume&Flux BAZ Ltd | Manufacturing | 2026 |
| Flux Corporation Ltd | Wholesale & retail | 2025 |
| FLV Logistics Ltd | Transport & logistics | 2024 |
| Flyaway Trips&Globecart Ltd | Wholesale & retail | 2026 |
| Flyera Trips&Tours Ltd | Administrative & support | 2026 |
| Flying Panther Ltd | Manufacturing | 2018 |
| FM & Sons (London) Limited | Transport & logistics | 2023 |
| FMF Plumbing Ltd | Construction | 2025 |
| FMR Ecommerce Ltd | Wholesale & retail | 2023 |
| Fmvision Build Ltd | Construction | 2024 |
| FNR Services Limited | Health & social care | 2015 |
| Fo-Stars Childcare Ltd | Health & social care | 2024 |
| Focus Findings UK Limited | Health & social care | 2009 |
| Focusnet Limited | Real estate | 2012 |
| Fola-Up Ltd | Wholesale & retail | 2024 |
| Follow the Phases Ltd | Information & communication | 2024 |
| Folybabe Ventures Ltd | Health & social care | 2011 |
| Food Safety & Hygiene Ltd | Education | 2023 |
| Foody Master Ltd | Wholesale & retail | 2026 |
| FOR the Soul Ltd | Other services | 2019 |
| FOR YT Ltd | Health & social care | 2023 |
| Forest-Dene Healthcare Services Limited | Health & social care | 2024 |
| Forever Unique Care Limited | Health & social care | 2022 |
| Forge View Metalworks Ltd | Manufacturing | 2025 |
| Form & Frame Co Building Services Ltd | Construction | 2024 |