| Fort Merchanting Limited | Wholesale & retail | 2017 |
| Fortress Developments Company Limited | Construction | 1982 |
| Fortress Security Solutions Ltd | Construction | 2019 |
| Fortuna Equity Partners Limited | Financial services | 2024 |
| Fortuna Investment Group Limited | Professional & scientific | 2011 |
| Fortuna Media Limited | Professional & scientific | 2012 |
| Forum Events & Media Group Ltd | Administrative & support | 2007 |
| Forum Events 2 Limited | Information & communication | 2018 |
| Forum Events Limited | Administrative & support | 1996 |
| Forum Events Media Limited | Administrative & support | 2012 |
| Forum Holdings 2 Limited | Financial services | 2023 |
| Forum Venue Finders Limited | Administrative & support | 2014 |
| Forza London Ltd | Information & communication | 2017 |
| Foster Electrics Ltd | Construction | 2024 |
| Fountain Drive Management Limited | Real estate | 2015 |
| Four Acorns Property Ltd | Real estate | 2017 |
| Four Rivers Coffee Company Ltd | Manufacturing | 2021 |
| Fourboys Limited | Administrative & support | 1999 |
| Fourth Foundry Ltd | Professional & scientific | 2020 |
| Fourthquarter Consultancy Limited | Professional & scientific | 2014 |
| Foxholes (Hertford) Management Limited | Households | 1990 |
| Foxholes Veterinary Clinic Limited | Professional & scientific | 2021 |
| Francis Plastering & Building Limited | Construction | 2018 |
| Frank L. Follett Motors Limited | Wholesale & retail | 1964 |
| Frankum & Kaye Limited | Wholesale & retail | 1962 |
| FRC Investment Services Limited | Administrative & support | 2018 |
| FRC Management Services Limited | Professional & scientific | 2018 |
| Fred & Ginger Hair & Beauty Limited | Other services | 2022 |
| Freedom Destinations Limited | Administrative & support | 2001 |
| Freedom Fitness Ltd | Arts & recreation | 2014 |
| Freelove Group Limited | Arts & recreation | 2005 |
| Freelove Holdings Limited | Financial services | 2009 |
| Fresh Heat Networks Ltd | Professional & scientific | 2020 |
| Fresh Limited | Administrative & support | 1995 |
| Fresh Salad Box Limited | Wholesale & retail | 2007 |
| Fresh Tracks Limited | Extraterritorial | 1999 |
| Friend Consultants Limited | Administrative & support | 2016 |
| Frogmore Hall Management Company Limited | Real estate | 2007 |
| Front Porch Productions Limited | Professional & scientific | 2019 |
| Frost Family Investment Company | Financial services | 2010 |
| Frost Family Investment Company Two | Financial services | 1935 |
| Frostline Ltd | Professional & scientific | 2018 |
| FSP Herts Ltd | Education | 2026 |
| FTA Advantage Limited | Other services | 2004 |
| FTA Finance Limited | Financial services | 2004 |
| FTA Financial & Wealth Management Limited | Administrative & support | 2016 |
| Fulham Herts Invest Limited | Financial services | 2025 |
| Fulham Herts Ltd | Real estate | 2024 |
| Full Belly Media Ltd | Information & communication | 2023 |
| Full Circle Productions (London) Ltd | Information & communication | 2015 |
| Fuller Colour Photography Limited | Professional & scientific | 2012 |
| Fumair Limited | Manufacturing | 1974 |
| FUN Fantastic (UK) Limited | Wholesale & retail | 2007 |
| Funk the Weekend Limited | Administrative & support | 2026 |
| FVB Collective Ltd | Arts & recreation | 2026 |
| FW Sports Limited | Extraterritorial | 2012 |
| G & C Education Limited | Education | 2024 |
| G C Plastering Ltd | Construction | 2025 |
| G E Cleaning Ltd | Administrative & support | 2019 |
| G Pickett Butchers Limited | Wholesale & retail | 2017 |
| G R Williams Limited | Health & social care | 2024 |
| G&P Property Estates Ltd | Real estate | 2020 |
| Gaia Impact Risk Ltd | Financial services | 2012 |
| Gainsborough Place Residents Company (NO.2) Limited | Households | 1995 |
| Galgorm Catering (ESW) | Wholesale & retail | 2020 |
| Galleons Green Limited | Information & communication | 1983 |
| Gallica Commodities Limited | Professional & scientific | 2025 |
| Gamels Consulting Ltd | Real estate | 2023 |
| Games YOU Loved Limited | Administrative & support | 2012 |
| Gamesprout Ltd | Information & communication | 2017 |
| Ganninon Limited | Professional & scientific | 2018 |
| Gannon Services Ltd | Professional & scientific | 2003 |
| Garden House Solicitors Ltd | Professional & scientific | 2011 |
| Garden on a Roll Limited | Wholesale & retail | 2007 |
| Gardens 4 Life Ltd. | Administrative & support | 2002 |
| Gardens for Life Design Limited | Extraterritorial | 2016 |
| Gardens for Life Limited | Administrative & support | 2000 |
| Gardens in a Box Limited | Professional & scientific | 2011 |
| Gardentime Designs Ltd | Other services | 2002 |
| Garuda Design Limited | Professional & scientific | 2012 |
| GAS Special Projects Ltd | Construction | 2021 |
| Gastons Cave Ltd | Arts & recreation | 2016 |
| Gate to QA Ltd | Information & communication | 2020 |
| Gateway Court (Bricket Wood) Management Company Limited | Households | 2007 |
| Gather Winery Ltd | Manufacturing | 2025 |
| Gavican Quinn Ltd | Manufacturing | 2017 |
| GBB Holborn Limited | Hospitality | 2023 |
| GBB Kings Cross Limited | Hospitality | 2023 |
| GBC Skims Plastering Ltd | Construction | 2025 |
| GC Express Couriers Ltd | Transport & logistics | 2025 |
| GDP Pharma Consulting Ltd | Professional & scientific | 2020 |
| Gdppc Properties Limited | Real estate | 2021 |
| Ge&Lu Contractors Ltd | Construction | 2022 |
| Generation 7 Consulting Ltd | Professional & scientific | 2023 |
| Genghis Optical Services Limited | Other services | 2008 |
| Gentle Tramp Limited | Administrative & support | 2025 |
| George & Dragon PUB Limited | Hospitality | 2025 |
| George Hersant Photography Ltd | Professional & scientific | 2020 |
| Gerri Davenport Ltd | Other services | 2017 |
| GGC Consulting Ltd | Professional & scientific | 2025 |