| Greycoat Placements Limited | Administrative & support | 1996 |
| Greywood Studio Ltd | Information & communication | 2026 |
| Gribson Estate Limited | Real estate | 2026 |
| GRID-1 Motorsport Ltd | Wholesale & retail | 2016 |
| Griffin Garage Doors and Glazing Ltd | Construction | 2023 |
| Griffolyon Ltd | Information & communication | 2023 |
| Grill Bay Ltd | Hospitality | 2020 |
| Grima Ventures Ltd | Administrative & support | 2020 |
| Grimes & Thorpe Developments Ltd | Administrative & support | 2014 |
| GRN Construction Ltd | Administrative & support | 2020 |
| Ground-To-Roof JET Washing Ltd | Administrative & support | 2026 |
| Grounded Fightwear Combat Co Ltd | Manufacturing | 2026 |
| GRS Assets Ltd | Real estate | 2025 |
| GRS Care Services Limited | Health & social care | 2023 |
| GS Heating Services Limited | Construction | 2012 |
| GS Retailing Ltd | Wholesale & retail | 2023 |
| GS United Enterprise Ltd | Households | 2026 |
| GSI Storage Ltd | Wholesale & retail | 2024 |
| GSY Buildings Renovated Ltd | Construction | 2025 |
| GT Consultancy Limited | Professional & scientific | 2023 |
| GT Sekhon Ltd | Health & social care | 2023 |
| GT Sekhon Properties Ltd | Real estate | 2025 |
| Gt&S Ltd | Construction | 2022 |
| Gtmx Consulting Ltd | Professional & scientific | 2024 |
| GTS247 Enterprises Ltd | Wholesale & retail | 2025 |
| GTT United Ltd | Wholesale & retail | 2019 |
| Guard Health Care Limited | Health & social care | 2024 |
| Guards River Club Limited | Hospitality | 2015 |
| Guddu Venture Limited | Wholesale & retail | 2025 |
| GUI Kang Ltd | Health & social care | 2014 |
| Guideon Limited | Administrative & support | 2003 |
| Guiding Stars SEN Club CIC | Health & social care | 2026 |
| Guinevere Road Limited | Households | 2020 |
| Gull’S Trading Limited | Wholesale & retail | 2026 |
| Gundogdu Trading Ltd | Hospitality | 2022 |
| Gunner Logistics Limited | Transport & logistics | 2025 |
| Guns N Posies Bakery Limited | Hospitality | 2023 |
| Gurjar Hindu Union (GHU) Ltd | Health & social care | 2006 |
| Gustavo Logistics Ltd | Transport & logistics | 2019 |
| Gutter and Roofing Ltd | Extraterritorial | 2021 |
| Guven Plumbers Limited | Construction | 2025 |
| GVI Properties Ltd | Real estate | 2026 |
| GW (Wood Green) Limited | Health & social care | 2014 |
| Gyebiwaa Limited | Health & social care | 2025 |
| Gyenimaa Holdings Limited | Wholesale & retail | 2025 |
| Gymnastics Competition League Limited | Arts & recreation | 2025 |
| Gymnax Ltd | Education | 2025 |
| Gymonkey Ltd | Wholesale & retail | 2024 |
| H & a Sharma Limited | Administrative & support | 2014 |
| H & S Kent Limited | Health & social care | 2015 |
| H Gill Capital Limited | Financial services | 2025 |
| H&A Private Limited | Other services | 2024 |
| H&M London Chauffeurs Ltd | Transport & logistics | 2026 |
| H.A.E Tea Room Limited | Hospitality | 2017 |
| H.E. Legal Services Limited | Professional & scientific | 2017 |
| H.E.A Catering Limited | Hospitality | 2018 |
| H.R.S. International Transport Limited | Transport & logistics | 1993 |
| H2A3 Trading Ltd | Wholesale & retail | 2015 |
| Habeebi's Grill Limited | Hospitality | 2025 |
| Habeebis Bites Limited | Manufacturing | 2026 |
| Habitat Management Property Ltd | Transport & logistics | 2020 |
| HAG Kortoci Construction Limited | Construction | 2026 |
| Haider Tourism Ltd | Arts & recreation | 2023 |
| Haines Commercials Ltd | Wholesale & retail | 2020 |
| Hairapy Ltd | Other services | 2006 |
| HAK Commerce Ltd | Wholesale & retail | 2026 |
| Halaansu Ltd | Real estate | 2024 |
| Hallan Investments Ltd | Real estate | 2022 |
| Hallan Properties LLP | | 2022 |
| Hallan Trading Ltd | Wholesale & retail | 2022 |
| Halley&Hopkins Ltd | Construction | 2021 |
| Halo Holidays Limited | Hospitality | 2025 |
| Halo Innovation Ltd | Manufacturing | 2020 |
| Halon Entertainment UK Limited | Information & communication | 2012 |
| Halsey Construction Ltd | Construction | 2016 |
| Halton House Dental Centre Ltd | Health & social care | 2007 |
| Hamilton Cars Ltd | Wholesale & retail | 2013 |
| Hamnaz Limited | Health & social care | 2020 |
| Hamza,S Khan Ltd | Wholesale & retail | 2025 |
| Handside Dental Surgery Limited | Health & social care | 2014 |
| Handyman Di&Ju Ltd | Construction | 2023 |
| Hannah Homes (Knebworth) Ltd | Construction | 2025 |
| Hannah Homes Investment Limited | Construction | 2018 |
| Hannets Consultants Ltd | Professional & scientific | 2010 |
| HANNEYX1 Limited | Health & social care | 2023 |
| Hanover Glass Solutions Ltd | Construction | 2013 |
| Hansaconsult Projects UK Limited | Education | 2026 |
| Haoli Ltd | Financial services | 2024 |
| Happi Pet Services Ltd | Professional & scientific | 2022 |
| Happy and Fit Ltd | Health & social care | 2022 |
| Happy Bears Early Years Ltd | Health & social care | 2025 |
| Happy Investment Property Limited | Hospitality | 2023 |
| Happyday GUS Limited | Financial services | 2015 |
| Harans (UK) Limited | Information & communication | 2002 |
| Harbour Holdings Limited | Real estate | 1937 |
| Harding Haulage Ltd | Transport & logistics | 2020 |
| Hardstaff Consulting Ltd | Information & communication | 2025 |
| Hari Environmental Services Limited | Professional & scientific | 2024 |
| Haris Toys Limited | Wholesale & retail | 2024 |
| Haris U Khan Limited | Transport & logistics | 2024 |