| Garel Flat Management Limited | Households | 2001 |
| Garner Facilities Services Limited | Administrative & support | 2009 |
| Garrett Race Fabrication Limited | Manufacturing | 2016 |
| Garry Bushell Enterprises Limited | Other services | 1997 |
| Gasonic Ltd | Administrative & support | 2017 |
| Gatti's Company Ltd | Construction | 2020 |
| Gayatri Investments Limited | Real estate | 2020 |
| Gaynesford Limited | Real estate | 2025 |
| GB Connect London Limited | Construction | 2025 |
| GB Creative Services Limited | Arts & recreation | 2017 |
| GBC Drywall Solutions Ltd | Construction | 2012 |
| GCL Management Ltd | Professional & scientific | 2023 |
| GCM Marble Limited | Construction | 2000 |
| GCM Taxi Limited | Transport & logistics | 2026 |
| GCR Holdings Limited | Real estate | 2019 |
| GDL Kent Limited | Construction | 2018 |
| Gdps Services Limited | Administrative & support | 1995 |
| Geartech Ltd | Manufacturing | 2018 |
| GEE Whizz Cleaning Ltd | Administrative & support | 2018 |
| Geeza Company Limited | Wholesale & retail | 2024 |
| Gelec Holdings Limited | Professional & scientific | 2017 |
| Gelttree Partners Limited | Professional & scientific | 2017 |
| Gemini Healthcare Limited | Health & social care | 2019 |
| Gemini Systems Limited | Information & communication | 1995 |
| Gemini Test Systems Limited | Information & communication | 2016 |
| Gemmant Property Limited | Real estate | 2017 |
| Genaiit Ltd | Extraterritorial | 2024 |
| Generic Business Solutions Limited | Information & communication | 1999 |
| Genesis Dental Ltd | Health & social care | 2018 |
| Genesta Developments Ltd | Construction | 2007 |
| Genxe Ltd | Information & communication | 2021 |
| Geographics Design Limited | Administrative & support | 2009 |
| George Alex Consultancy Limited | Financial services | 2024 |
| George Howard Packaging Limited | Real estate | 1995 |
| George Parker Associates Limited | Wholesale & retail | 2019 |
| Georgio’S GAS & Heating Services Limited | Construction | 2021 |
| GEP IT Solutions Ltd | Information & communication | 2024 |
| GET Active Kids Ltd | Health & social care | 2023 |
| GH Interior Glass Limited | Construction | 2005 |
| Ghaa QS Services Ltd | Professional & scientific | 2022 |
| Gibbo Solutions Ltd | Real estate | 2025 |
| Gifthair Ltd | Other services | 2026 |
| Gilbert's (Holdings) Limited | Real estate | 1957 |
| Gillarenko Limited | Real estate | 2022 |
| Gina Bryant Wellbeing Limited | Health & social care | 2026 |
| Gina Pietrzak Travel Ltd | Hospitality | 2023 |
| Gingals Limited | Information & communication | 2014 |
| Ginkgo Digital Limited | Administrative & support | 2018 |
| GIVE4HOPE Limited | Education | 2025 |
| Gjana Property Investment Ltd | Real estate | 2025 |
| Gjfx Ltd | Financial services | 2020 |
| GK Estates London Ltd | Construction | 2016 |
| GKC (Services) Limited | Other services | 2014 |
| GKT Advisors Limited | Professional & scientific | 2022 |
| GL Quantum Limited | Administrative & support | 2025 |
| Glam Aesthetics Blackfen Ltd | Other services | 2025 |
| Glam by Toya Ltd | Wholesale & retail | 2018 |
| Glam Nails Spa Limited | Other services | 2026 |
| Glare Retain Limited | Professional & scientific | 2025 |
| Glass Window Cleaning Limited | Administrative & support | 2023 |
| Glass Wizard Limited | Other services | 2021 |
| Glebe Blackheath Ltd | Real estate | 2021 |
| Glencairn Property Estates 28 Ltd | Real estate | 2025 |
| Glencairn Property Estates Ltd | Real estate | 2022 |
| Global Admin Limited | Administrative & support | 2017 |
| Global Consult Limited | Administrative & support | 2020 |
| Global Digitisation Limited | Administrative & support | 2021 |
| Global Harvest Church (London) | Other services | 2005 |
| Global Opus LLP | | 2024 |
| Global Payment Network Ltd | Financial services | 2018 |
| Global Spare Parts Limited | Wholesale & retail | 2018 |
| Globalverse UK Limited | Professional & scientific | 2024 |
| Glorious Ideas Ltd | Information & communication | 2010 |
| GLS Heating Limited | Construction | 2018 |
| GM Security & Electrical Limited | Construction | 2022 |
| GMS Consulting Limited | Professional & scientific | 2021 |
| GMS International Resources Limited | Other services | 2015 |
| GMT Accounting Ltd | Professional & scientific | 2019 |
| GMT Restorations & Conservation Ltd | Construction | 2015 |
| Gndm Ltd | Administrative & support | 2025 |
| Go Direct Group Limited | Construction | 2007 |
| Goal-Line Partners Ltd | Other services | 2025 |
| Godwin Accounting Limited | Professional & scientific | 2025 |
| Gogero Limited | Construction | 2016 |
| Gold Barber Irina Ltd | Other services | 2017 |
| Goldberg Services Limited | Health & social care | 2019 |
| Goldem Property Management Limited | Professional & scientific | 2017 |
| Golden Crown Services Ltd | Wholesale & retail | 2025 |
| Golden Star Capital Limited | Real estate | 2018 |
| Golden Vision Ltd | Administrative & support | 2021 |
| Goldenbrick Surveying Limited | Professional & scientific | 2025 |
| Goldhawk Investments Ltd | Administrative & support | 2025 |
| Goldion Ltd | Construction | 2025 |
| Goldsel North Limited | Real estate | 2022 |
| Goldsystem Operations Limited | Construction | 2015 |
| Good Chat Coaching Ltd | Administrative & support | 2025 |
| Good Leaver Limited | Other services | 2020 |
| Goodwin Heights Management Company Ltd | Real estate | 2012 |
| Gordon Grove Garage Limited | Transport & logistics | 1981 |
| Gorgeous Blooms Ltd | Wholesale & retail | 2024 |