| Fusion Childcare Services | Education | 2011 |
| Futurescope Film Productions Limited | Arts & recreation | 2017 |
| Futurewave Limited | Administrative & support | 2018 |
| FY Services Limited | Professional & scientific | 2022 |
| FYI Analytics Ltd | Professional & scientific | 2024 |
| FYI Consulting Limited | Information & communication | 2011 |
| G Byte Consulting & IT Services Ltd | Information & communication | 2005 |
| G.J.Pope Limited | Wholesale & retail | 2018 |
| GA Marketing Research Consultancy Limited | Wholesale & retail | 2019 |
| Gable Consultancy Ltd | Wholesale & retail | 2024 |
| Gadget Geek Online Ltd | Wholesale & retail | 2019 |
| Gainsborough Sales Limited | Wholesale & retail | 1999 |
| Galfav Limited | Professional & scientific | 2009 |
| Gallivan Schmidt Hospitality Ltd | Hospitality | 2026 |
| Games Leadership Academy Limited | Education | 2023 |
| Games Leadership Limited | Education | 2023 |
| Games Leadership Network CIC | Health & social care | 2022 |
| Gaminet Solutions Limited | Financial services | 2023 |
| Garage Doors (London) Limited | Administrative & support | 1976 |
| Garage Doors Direct Ltd | Wholesale & retail | 2021 |
| Garage Doors Limited | Administrative & support | 1992 |
| Garcias Kitchen Limited | Hospitality | 2025 |
| Gaskell & Chambers Limited | Wholesale & retail | 2014 |
| Gatehall Services Limited | Real estate | 2007 |
| Gatekey Properties Limited | Real estate | 2024 |
| Gatespring Limited | Real estate | 2006 |
| Gazapi Sport Ltd | Manufacturing | 2019 |
| Gbau Limited | Professional & scientific | 2024 |
| GCB Tutors Limited | Education | 2025 |
| Gcops Ltd. | Professional & scientific | 2016 |
| GDL Sales Consulting Ltd | Professional & scientific | 2017 |
| GEA Consultancy Limited | Wholesale & retail | 2021 |
| Gemini Trading (Harpenden) Limited | Wholesale & retail | 2006 |
| Generation POP Limited | Information & communication | 2018 |
| Genesis Aesthetics Limited | Health & social care | 2018 |
| Genesis Data Ltd | Information & communication | 2021 |
| Genesis Search Ltd | Administrative & support | 2021 |
| Genetic Technologies Limited | Professional & scientific | 1998 |
| Geneva Wealth Limited | Financial services | 2015 |
| Genuinely Outstanding Ltd | Professional & scientific | 2026 |
| Geomatic Survey & Measurement Services Limited | Other services | 2020 |
| George Cowley Consulting Ltd | Professional & scientific | 2024 |
| Gerroa Limited | Professional & scientific | 2024 |
| GET Buff With Reets Ltd | Arts & recreation | 2024 |
| GI Care Group Limited | Health & social care | 2020 |
| Gibbons Advisors Limited | Professional & scientific | 2022 |
| Gigi Properties Limited | Real estate | 2021 |
| Ginbottle Ltd | Professional & scientific | 2025 |
| Ginger Chateaux Ltd | Real estate | 2012 |
| Girl Planner Ltd | Professional & scientific | 2018 |
| GJ Consulting Services Limited | Professional & scientific | 2002 |
| GKC Productions Limited | Information & communication | 2009 |
| GKS Building Consultancy Ltd | Extraterritorial | 2022 |
| GKS Building Consultants Ltd | Real estate | 2003 |
| Gladco Ltd | Professional & scientific | 2025 |
| Glanwith Limited | Professional & scientific | 1990 |
| GLE Telecoms Ltd | Information & communication | 2024 |
| Glengar Properties Ltd | Hospitality | 2022 |
| Global Merchandise Solutions Limited | Manufacturing | 2011 |
| Global Partners Investments (UK) Limited | Financial services | 2022 |
| Global Payment Processing Leader Limited | Information & communication | 2023 |
| GLOBAL55 Ltd | Construction | 2019 |
| Glyn Griffiths (Jewellers) Limited | Wholesale & retail | 1978 |
| Goag Limited | Wholesale & retail | 2025 |
| Golden Hands Care Limited | Health & social care | 2014 |
| Golden Scissors Bury Limited | Other services | 2016 |
| Golden Scissors Harpenden Ltd | Other services | 2020 |
| Goldhawk Lofts Limited | Construction | 2014 |
| Goldhouse Accounting Ltd | Professional & scientific | 2018 |
| Golf Course Management Services Ltd | Professional & scientific | 2020 |
| Golf Experience Ltd | Wholesale & retail | 2012 |
| Gone Fish Inns Limited | Hospitality | 2002 |
| Goobe Construction Solutions Ltd | Construction | 2020 |
| Good Decisions Limited | Professional & scientific | 2016 |
| Good Intent Developments (Jarvis) Limited | Construction | 2023 |
| Good Structural Engineers Ltd | Professional & scientific | 2013 |
| Goode Numbers Limited | Professional & scientific | 2019 |
| Goodwins Property Ltd | Real estate | 2022 |
| Gorselands Residents Association Limited | Administrative & support | 2015 |
| Gosling Creative Limited | Manufacturing | 2010 |
| Gowan Crop Protection Limited | Agriculture & fishing | 2015 |
| GPI2 (UK) Limited | Financial services | 2024 |
| Grail Five LLP | | 2017 |
| Grampos Import, Export and Global Solutions (UK) Limited | Wholesale & retail | 2023 |
| Granary Squared Properties Limited | Real estate | 2021 |
| Grandpont Holdings Ltd | Real estate | 2024 |
| Grandsden Flat Management Company Limited | Households | 1983 |
| Grange Asset Management Limited | Extraterritorial | 2011 |
| Grangeway Housing Partners Limited | Households | 2015 |
| Grangeway Investments Ltd | Real estate | 2018 |
| Graphic Building Products Ltd | Construction | 2018 |
| Gravitas Motive Ltd | Other services | 2024 |
| Gravity 7 Ltd | Information & communication | 2019 |
| Gray Tennis Ltd | Administrative & support | 2022 |
| GRC Automotive Ltd | Wholesale & retail | 2026 |
| Green Allies Limited | Professional & scientific | 2021 |
| Green Communications Group Ltd | Professional & scientific | 2020 |
| Green Heritage Developments Ltd | Construction | 2023 |
| Green Heritage Group Ltd | Construction | 2020 |
| Green Lawns Close Management Company Limited | Real estate | 2012 |