| Grittyboyz Ltd | Wholesale & retail | 2024 |
| Grivon Solutions Limited | Information & communication | 2017 |
| GRM Autotech Ltd | Wholesale & retail | 2026 |
| GRO UP Business Network Ltd | Professional & scientific | 2025 |
| Gromax Business Solutions Limited | Professional & scientific | 2012 |
| Grooves for Good Ltd | Arts & recreation | 2025 |
| Grosik (High Wycombe) Limited | Wholesale & retail | 2015 |
| Groves Harling Properties Ltd | Households | 2025 |
| Groveshire Homes Ltd | Real estate | 2022 |
| Groveside Homes Limited | Extraterritorial | 1967 |
| Grovewood General Insurance Services Ltd | Financial services | 2004 |
| Grovewood Insurance Services Limited | Financial services | 1995 |
| Grow Together - Bucks CIC | Agriculture & fishing | 2020 |
| Growth Hutch Digital Ltd | Information & communication | 2023 |
| GRP Real Estate Limited | Real estate | 2023 |
| GRP423 Real Estate Ltd | Real estate | 2025 |
| Grpc Real Estate Limited | Real estate | 2024 |
| GRS (Middle East) Limited | Professional & scientific | 2009 |
| Gruv Ltd | Wholesale & retail | 2026 |
| Grymsdyke Gallery Ltd | Professional & scientific | 2013 |
| GS & SK Properties Ltd | Construction | 2024 |
| GS Accountants Oxford Ltd | Professional & scientific | 2018 |
| GS Acquisitions Limited | Professional & scientific | 2010 |
| GS Cars UK Ltd | Wholesale & retail | 2021 |
| GS Payroll Services Ltd | Administrative & support | 2021 |
| GSB JSB Limited | Real estate | 2025 |
| GSD Developments Ltd | Construction | 2017 |
| Gset Health Ltd | Health & social care | 2025 |
| GSP17 Ltd | Professional & scientific | 2023 |
| GSR Limited | Information & communication | 2024 |
| Gsshealth Ltd | Professional & scientific | 2025 |
| Gtbj Limited | Wholesale & retail | 2025 |
| Gtbsj Ltd | Real estate | 2025 |
| Gtgj Consulting Ltd | Professional & scientific | 2015 |
| GTJ Group Limited | Professional & scientific | 2017 |
| Guardhome Limited | Construction | 2004 |
| Gudsh I.T. Limited | Information & communication | 2010 |
| Guestband Ltd | Information & communication | 2018 |
| Guildford City Football Club Limited | Arts & recreation | 2024 |
| Guitar Parts UK Limited | Wholesale & retail | 2019 |
| GUL Constructions Ltd | Construction | 2019 |
| Gul's Grill Tandoori Ltd | Hospitality | 2024 |
| Gulex Ltd | Information & communication | 2018 |
| Gulistan Limited | Wholesale & retail | 2025 |
| Guls Grill & Curry Ltd | Hospitality | 2022 |
| Gunilda Ltd | Wholesale & retail | 2024 |
| Gunjan Bolton Gillespie Investments Limited | Real estate | 2025 |
| Guron Estates Limited | Other services | 2022 |
| Gursel Restaurant Ltd | Hospitality | 2021 |
| Guru TEG Bahadur Ltd | Professional & scientific | 2025 |
| Gurunanda UK Limited | Wholesale & retail | 2024 |
| Guud Accountants Limited | Professional & scientific | 2023 |
| Gwnw City Developments Limited | Professional & scientific | 2005 |
| GWS Windows and Plastic Centre Ltd | Manufacturing | 2018 |
| GX Builds Ltd | Construction | 2023 |
| Gym Wise Install Ltd | Arts & recreation | 2021 |
| Gzcc Ltd | Information & communication | 2015 |
| GZT Limited | Health & social care | 2012 |
| GZT Properties Limited | Real estate | 2015 |
| H & H Electrical Contractors (Maidenhead) Ltd | Construction | 2017 |
| H & J Basra Enterprises Limited | Financial services | 2024 |
| H & T Property Investments Ltd | Real estate | 2024 |
| H & Z Property Investments Limited | Real estate | 2023 |
| H a Motors Ltd | Wholesale & retail | 2017 |
| H Group London Limited | Professional & scientific | 2025 |
| H H & L School Support Services Limited | Education | 2016 |
| H H Rentals Limited | Real estate | 2018 |
| H P a Associates Ltd | Professional & scientific | 2014 |
| H&D Essentials Ltd | Wholesale & retail | 2023 |
| H&G FAM Property Ltd | Real estate | 2025 |
| H&H Business Limited | Wholesale & retail | 2025 |
| H&H Collective Ltd | Wholesale & retail | 2026 |
| H&U Interiors Limited | Wholesale & retail | 2025 |
| H-Modul Limited | Extraterritorial | 2005 |
| H.C. COX Ltd | Construction | 2007 |
| H.G. Rant Ltd | Manufacturing | 2004 |
| H.I.L.S Pharma Limited | Administrative & support | 2026 |
| H.L. Smith Securities Limited | Construction | 1987 |
| H.M Creation Limited | Manufacturing | 2025 |
| H12 Services Limited | Other services | 2009 |
| H2O Land and Property Ltd | Real estate | 2023 |
| H2O Plumbing (Oxford) Ltd | Construction | 2015 |
| H2ST Solutions Ltd | Transport & logistics | 2024 |
| Habibi Scents Ltd | Wholesale & retail | 2024 |
| Habispace Ltd | Professional & scientific | 2015 |
| Habology Ltd | Construction | 2023 |
| Hackett's Food and Drink Company (Witney) Limited | Hospitality | 2017 |
| Hackett's Harbour Limited | Hospitality | 2016 |
| Hacketts Group (UK) Limited | Hospitality | 2013 |
| Hacketts Homecare Limited | Health & social care | 2010 |
| Hackett’S Food and Drink (Stow 2020) Limited | Hospitality | 2020 |
| Hackshaw TM Ltd | Construction | 2025 |
| Haden Fire & Security Ltd | Construction | 2012 |
| Hadenbell Limited | Professional & scientific | 2010 |
| Hadi Murad Limited | Wholesale & retail | 2022 |
| Haerfest Limited | Agriculture & fishing | 2024 |
| Hair & Make-Up by Erin Jane Steadman Limited | Information & communication | 2019 |
| Hair Blaster UK Limited | Other services | 2020 |
| Hairblends Limited | Manufacturing | 2016 |
| Haircare Experts Ltd | Other services | 2015 |