| FES Education Consultants UK Ltd | Education | 2021 |
| FF Security Solutions Ltd | Information & communication | 2020 |
| Ffka Ltd | Wholesale & retail | 2025 |
| FGS Homes Ltd | Real estate | 2026 |
| FHB (Rainham) Limited | Professional & scientific | 1998 |
| FHF Railway Ltd | Other services | 2025 |
| Fichis UK Limited | Wholesale & retail | 2026 |
| Fidelis Marketing Group Ltd | Other services | 2026 |
| Filmax Ltd | Administrative & support | 2021 |
| Finaffairs Consulting Ltd | Wholesale & retail | 2012 |
| Finance Solutions & Advisors Ltd | Professional & scientific | 2020 |
| Find My Staff Ltd | Administrative & support | 2021 |
| Fire Alarm Solutions Limited | Construction | 2002 |
| Fire Door Compliance Ltd | Professional & scientific | 2025 |
| Firefly Service Provider Ltd | Information & communication | 2023 |
| Firelectric Limited | Construction | 2026 |
| First Call Engineering Ltd | Manufacturing | 2016 |
| First Class Ventilation Ltd | Construction | 2013 |
| First for Coreskills Limited | Professional & scientific | 2018 |
| Firstmove Labs Ltd | Information & communication | 2025 |
| Fismayor Limited | Construction | 2022 |
| Five N Five Ltd | Wholesale & retail | 2021 |
| Five Star Spring Cleaning Limited | Administrative & support | 2023 |
| Five to One Ltd | Professional & scientific | 2019 |
| FJC Topco Limited | Water & waste | 2013 |
| Flashmove Logistics Ltd | Transport & logistics | 2025 |
| Flex Chicken Ltd | Hospitality | 2026 |
| Flightnest Ltd | Administrative & support | 2025 |
| Flintham Cabins Limited | Other services | 1988 |
| Flower Thai Massage & Beauty Hornchurch Ltd | Other services | 2020 |
| Flxq Ltd | Construction | 2026 |
| Flying B Apparel Limited | Wholesale & retail | 2024 |
| FM Crown Trades Ltd | Wholesale & retail | 2023 |
| FMC Logistics (UK) Ltd | Transport & logistics | 2010 |
| FML Waste Solutions Limited | Water & waste | 2022 |
| FMV Contractors Ltd | Construction | 2024 |
| FN Care Services Ltd | Administrative & support | 2024 |
| Focus Action Limited | Professional & scientific | 2001 |
| Fola Case Consulting Limited | Administrative & support | 2017 |
| Follow Sign Driving School Limited | Education | 2023 |
| FOR Love & Soul Ltd | Hospitality | 2020 |
| Foreign-Official Limited | Information & communication | 2026 |
| Forest Freight Limited | Transport & logistics | 1971 |
| Forge & File 1935 Ltd | Wholesale & retail | 2025 |
| Formix Build Ltd | Construction | 2026 |
| Fortador Detailing Ltd | Wholesale & retail | 2025 |
| Fortis Property Capital Ltd | Real estate | 2025 |
| FORTUN8 Consulting Ltd | Information & communication | 2016 |
| FORTUN8 Healthcare Solutions Ltd | Health & social care | 2023 |
| Fortunegate Investments Ltd | Real estate | 2024 |
| Foundry AI Ltd | Information & communication | 2026 |
| Fountain Care Services Ltd | Health & social care | 2023 |
| Fowson Limited | | 1985 |
| FP Contractors Ltd | Construction | 2024 |
| Franchise 88.COM Ltd | Professional & scientific | 2018 |
| Frankjay Ltd | Construction | 2023 |
| Frankphil Childcare Limited | Education | 2018 |
| FRD Garage Ltd | Wholesale & retail | 2025 |
| Frederick Holdings Ltd | Financial services | 2025 |
| Freds Motors Ltd | Wholesale & retail | 2025 |
| Freedom Sems Limited | Real estate | 2020 |
| Freight Exchange Ltd | Transport & logistics | 2014 |
| Freshserve Ltd | Wholesale & retail | 2025 |
| From-S to S Ltd | Construction | 2024 |
| Frontline K9 Services Ltd | Administrative & support | 2025 |
| Frontlot Property Management Limited | Extraterritorial | 1990 |
| FSB Construction Ltd | Construction | 2010 |
| FSE Developments Limited | Construction | 2020 |
| Full Circuit Solutions Limited | Construction | 2014 |
| Full Measures Recruitment Ltd | Administrative & support | 2017 |
| Full Monty 1 Limited | Extraterritorial | 2018 |
| Full Monty Barbers Ltd | Other services | 2025 |
| Furniture Delivery Network Limited | Transport & logistics | 2012 |
| Fusion Vehicle Repair Ltd | Wholesale & retail | 2026 |
| Future Express Ltd | Construction | 2019 |
| Future Home Constructions Ltd | Construction | 2021 |
| Future Home Properties Ltd | Real estate | 2026 |
| Future KIN CIC | Education | 2026 |
| Fystamlya Limited | Health & social care | 2022 |
| Fzal IT Limited | Information & communication | 2025 |
| Fzco Accountants Limited | Professional & scientific | 2017 |
| G & S Construction(Uk) Ltd | Construction | 2023 |
| G S Psychoanalysis Ltd | Health & social care | 2016 |
| G Star Tyres Ltd | Wholesale & retail | 2026 |
| G Tunnel Rail Ltd | Construction | 2015 |
| G&B Homes Limited | Construction | 2014 |
| G&J Entertainment Ltd | Arts & recreation | 2021 |
| G&K 4U Ltd | Hospitality | 2021 |
| G.D Drylining Ltd | Construction | 2023 |
| GA WAH Rainham Ltd | Hospitality | 2025 |
| Gadgets Xpress Limited | Wholesale & retail | 2016 |
| Galata Rainham Limited | Hospitality | 2025 |
| Gallant Rogue Ltd | Information & communication | 2018 |
| Galley Maintenance Ltd | Construction | 2026 |
| Gamma Consult Ltd | Information & communication | 2015 |
| Gardens Design & Build Ltd | Administrative & support | 2022 |
| Garratt Homes Limited | Construction | 2019 |
| Garrett Support Services Ltd | Administrative & support | 2017 |
| Garuta Health Care Limited | Health & social care | 2016 |
| Gashi Properties Ltd | Hospitality | 2024 |