| Flowline Systems Ltd | Manufacturing | 2006 |
| Fluidsoft Ltd | Information & communication | 2013 |
| Fluorocycle Ltd | Water & waste | 2026 |
| FMP Consulting Limited | Administrative & support | 2024 |
| Ford Farm Lodges Limited | Real estate | 2021 |
| Forensic Analytics Ltd | Information & communication | 2013 |
| Forget ME DO Limited | Information & communication | 2014 |
| FORM1 Partners Ltd | Professional & scientific | 2023 |
| Fortem Energy Services Limited | Construction | 1991 |
| Fortem Holdings Limited | Extraterritorial | 1975 |
| Fortem Solutions Limited | Construction | 2003 |
| Fortus Beds Limited | Manufacturing | 2000 |
| Fortus East Mids Limited | Manufacturing | 1999 |
| Fortus England & Wales Limited | Manufacturing | 2002 |
| Fortus Group Holdings Limited | Financial services | 2019 |
| Fortus Hampshire Limited | Manufacturing | 1992 |
| Fortus Kent Limited | Manufacturing | 1999 |
| Fortus Norfolk Limited | Manufacturing | 2008 |
| Fortus North West Limited | Manufacturing | 2002 |
| Fortus South West Limited | Manufacturing | 1999 |
| Fortus West Mids Limited | Manufacturing | 2005 |
| Fortus Yorkshire Limited | Manufacturing | 2006 |
| Forward Slash Films Ltd | Information & communication | 2007 |
| Forza Ventures Ltd | Professional & scientific | 2023 |
| Foss Innovation Ltd | Professional & scientific | 2011 |
| Foster & Shackell Limited | Construction | 2005 |
| FOX & Duck Limited | Real estate | 2021 |
| Fox-A-Gon Limited | Professional & scientific | 2020 |
| Freehold Investments Limited | Real estate | 2024 |
| Freightlink Transport Limited | Transport & logistics | 2003 |
| Front Runners Limited | Wholesale & retail | 2008 |
| Frosts Landscapes Trustees Limited | Administrative & support | 2024 |
| FTG Electrical Ltd | Extraterritorial | 2023 |
| Full Focus Property Videos Ltd | Information & communication | 2011 |
| Funll Limited | Information & communication | 2021 |
| Furlong & Higgs Properties Limited | Construction | 2012 |
| Furlong and Higgs Limited | Construction | 1994 |
| Fusion Elements Limited | Professional & scientific | 2024 |
| Future of IT Ltd | Information & communication | 2020 |
| Futureheads Recruitment Limited | Administrative & support | 2009 |
| Fxtsolutions Ltd | Wholesale & retail | 2019 |
| Fylde Solar Holding Limited | Financial services | 2015 |
| Fylde Solar Limited | Energy | 2019 |
| Fyne Consulting Ltd | Professional & scientific | 2024 |
| Fynw Flower Studio Limited | Wholesale & retail | 2022 |
| G & T Electrical Limited | Construction | 2021 |
| G Davies Electrical Services Ltd | Construction | 2022 |
| G.P. Woods Limited | Extraterritorial | 1973 |
| GAD Brentwood Limited | Health & social care | 2023 |
| GAD Canada Limited | Health & social care | 2022 |
| GAD Canary Wharf Limited | Health & social care | 2020 |
| GAD Kensington Limited | Health & social care | 2024 |
| GAD Kngs Road Limited | Health & social care | 2024 |
| GAD NAD Life Limited | Health & social care | 2024 |
| GAD NH Limited | Health & social care | 2024 |
| GAD Shoreditch Limited | Health & social care | 2020 |
| GAD Stratford Limited | Health & social care | 2024 |
| GAD White City Limited | Health & social care | 2020 |
| Gade Enterprises Ltd | Wholesale & retail | 2010 |
| Galasso Signs Limited | Manufacturing | 1998 |
| Garashield Limited | Information & communication | 2016 |
| Gardamed Limited | Manufacturing | 2016 |
| Garden Building Services Limited | Wholesale & retail | 2006 |
| Garden City Associates Limited | Information & communication | 2014 |
| Garden City Brewery Limited | Manufacturing | 2016 |
| Garden City Homes Limited | Construction | 2014 |
| Garden City Nails Ltd | Other services | 2025 |
| Garden City Scientific Limited | Wholesale & retail | 2021 |
| Garnett Professional Development Ltd | Education | 2014 |
| Garrison Court Freeholders Limited | Construction | 2017 |
| Gathr'D Limited | Information & communication | 2025 |
| Gatmerk Ltd | Manufacturing | 2025 |
| Gauldie Way Management Company Limited | Households | 1993 |
| Gazzia Solutions Limited | Professional & scientific | 2021 |
| GB Recycling Ltd | Professional & scientific | 2014 |
| GD Ritchie Consulting Ltd | Professional & scientific | 2023 |
| Gear Services (Letchworth) Limited | Manufacturing | 2003 |
| Gelson Optimal Limited | Wholesale & retail | 2018 |
| George Parnell Ltd | Professional & scientific | 2025 |
| Georgiou Communications Ltd | Information & communication | 2023 |
| GET a Drip Limited | Health & social care | 2016 |
| GET a Drip Operations Limited | Health & social care | 2020 |
| GET a Drip Pharma Limited | Health & social care | 2020 |
| GET a Drip Real Estate Limited | Real estate | 2021 |
| GG-600-986 Limited | Real estate | 2021 |
| Gidda Investments Limited | Real estate | 2018 |
| Gilbert & Gregson Construction Limited | Construction | 2014 |
| Gjfm Limited | Households | 2025 |
| GK Children's Care Ltd | Health & social care | 2026 |
| Gladtags (UK) Ltd | Construction | 2012 |
| Glamour Nails Letchworth Limited | Real estate | 2024 |
| GLJ Pubs Limited | Hospitality | 2018 |
| Global Creative Consulting and Outsourcing Ltd | Information & communication | 2023 |
| Globe Property Management Limited | Real estate | 2011 |
| Globeits Ltd | Wholesale & retail | 2024 |
| Glowbal Skincare Clinics Ltd | Wholesale & retail | 2021 |
| Go Forth Productions Ltd | Information & communication | 2025 |
| Go Getters Delivery Limited | Wholesale & retail | 2016 |
| Go Go BAB Ltd | Hospitality | 2024 |
| Go PAD Limited | Real estate | 1992 |