| Greener Future Developments Limited | Real estate | 2020 |
| Greenwings Ecology Ltd | Professional & scientific | 2025 |
| Greg Bedford Ltd | Professional & scientific | 2010 |
| Greybutterflyink Limited | Manufacturing | 2025 |
| Gridline Energy Solutions Ltd | Construction | 2026 |
| GRIFFO1311 Limited | Professional & scientific | 2017 |
| Grosh Construction Ltd | Construction | 2013 |
| Grove Associates Ltd | Professional & scientific | 2023 |
| Grove Mill Place (Carshalton) Residents Company Limited | Households | 1999 |
| Grove Park Villas Management Company Limited | Extraterritorial | 2015 |
| GSG Wizard Bodyworks Ltd | Wholesale & retail | 2023 |
| Gsvl Properties Ltd | Real estate | 2022 |
| Guild Home Improvements Limited | Construction | 2002 |
| Gupta Solutions Ltd | Information & communication | 2016 |
| Guptas Properties Ltd | Real estate | 2019 |
| Guru Harkishan Ltd | Wholesale & retail | 2025 |
| GX Language Services Ltd | Professional & scientific | 2024 |
| Gyimah Enterprise Ltd | Administrative & support | 2025 |
| H & H Enterprise (Carshalton) Ltd | Other services | 2018 |
| H&A Business Consultants Limited | Professional & scientific | 2015 |
| H&M Accountants Ltd | Professional & scientific | 2024 |
| H&M Retail Limited | Wholesale & retail | 2022 |
| H&P Property Ltd | Real estate | 2019 |
| H.E. Matthews Pharmacy Limited | Wholesale & retail | 2010 |
| H.S Endodontics Ltd | Health & social care | 2023 |
| H2O DRY Cleaners Ltd | Other services | 2019 |
| Habibi Car Rental and Sales Ltd | Wholesale & retail | 2025 |
| Hair of the Dog Limited | Hospitality | 2003 |
| Haksons Ltd | Real estate | 2024 |
| Halal Meat & Groceries Ltd | Wholesale & retail | 2026 |
| Halls Bullz Ltd | Transport & logistics | 2021 |
| Halls Bullz Property Limited | Real estate | 2025 |
| Halu Home Limited | Professional & scientific | 2024 |
| Hands-On Computers Limited | Information & communication | 1995 |
| Hannah Flowers Counselling Limited | Health & social care | 2020 |
| Hannah Little Ltd | Health & social care | 2024 |
| Hansen's Family Homes Ltd | Real estate | 2016 |
| Hansford and Son's Flooring Limited | Construction | 2015 |
| Hants Grab & Go Ltd | Real estate | 2026 |
| Happibe Ltd | Information & communication | 2020 |
| Happy Home LU Ltd | Health & social care | 2024 |
| Happy Takeaway Ltd | Hospitality | 2023 |
| Happy Tracks Entertainment Ltd | Health & social care | 2026 |
| Hardy Property Management Limited | Real estate | 2019 |
| Harini Enterprises Ltd | Wholesale & retail | 2026 |
| Harini Housing Limited | Real estate | 2020 |
| Harizun Ltd | Information & communication | 2024 |
| Harman's Property Maintenance Ltd | Construction | 2023 |
| Harpridge Limited | Manufacturing | 1992 |
| Harrington Brothers Limited | Administrative & support | 2009 |
| Harris Brothers Ltd | Construction | 2006 |
| Harris Sisters Property Ltd | Real estate | 2021 |
| Harson Auto Ltd | Wholesale & retail | 2024 |
| Hat-Trick Design Consultants (London) Limited | Professional & scientific | 2015 |
| Haus Vermiete Ltd | Real estate | 2022 |
| Haven & Co Properties Limited | Households | 2017 |
| Hawk Construction South Limited | Construction | 2016 |
| Hawken & Frost Rentals Ltd | Real estate | 2025 |
| Hawken & LEE Rentals Ltd | Real estate | 2025 |
| Hawken Estates Ltd | Real estate | 2024 |
| Hawken Rentals Ltd | Real estate | 2024 |
| Haxton Media Limited | Manufacturing | 2022 |
| Hayes Meridian Group Limited | Professional & scientific | 2011 |
| Haylis UK Ltd | Wholesale & retail | 2022 |
| Health Mastery World Ltd | Education | 2023 |
| Healthovate Ltd | Information & communication | 2025 |
| Heat Pump 4 YOU Ltd | Construction | 2024 |
| Heating and Cooling Specialists Limited | Construction | 2026 |
| Heatversity Ltd | Construction | 2016 |
| Heaven Heights Ltd | Real estate | 2024 |
| Helen Burrows Consulting Ltd | Professional & scientific | 2026 |
| Helios Capital Investment Ltd | Construction | 2025 |
| Helios Healthcare Ltd | Professional & scientific | 2025 |
| Hendon United Sports Club | Arts & recreation | 2009 |
| Henga Holdings Ltd | Real estate | 2023 |
| Her.B Nutrition Ltd | Wholesale & retail | 2020 |
| HHC Retail Ltd | Wholesale & retail | 2017 |
| Hidden Gems Daycare Ltd | Health & social care | 2020 |
| High Grade Teaching Ltd | Education | 2017 |
| High Voltage Ltd | Wholesale & retail | 2015 |
| Highley Homes Ltd | Real estate | 2024 |
| HIQ Heating & Plumbing Crew Ltd | Construction | 2023 |
| HK Hope Recovery & Skills Centre CIC | Other services | 2026 |
| HMK Investment Ltd | Real estate | 2019 |
| HNO Ltd | Real estate | 2017 |
| HNT Properties Ltd | Real estate | 2021 |
| Hoang Consultant Ltd | Professional & scientific | 2018 |
| Hodge Podge Community Arts CIC | Arts & recreation | 2022 |
| Hodgepodge Arts Ltd | Arts & recreation | 2022 |
| Hoffman and Riss Advisory Services Limited | Professional & scientific | 2016 |
| Hogg Fruit & VEG Ltd | Hospitality | 2015 |
| Holder Air Conditioning Limited | Energy | 2015 |
| Home Standards Limited | Professional & scientific | 2021 |
| Home-Start Sutton | Health & social care | 2004 |
| Homebest Limited | Information & communication | 2019 |
| Homes 2 Love Ltd | Real estate | 2016 |
| Homra Ltd | Wholesale & retail | 2024 |
| Hopkins Fs&E Ltd | Transport & logistics | 2021 |
| Hotelier Help Ltd | Administrative & support | 2022 |
| Hotsparkle Ltd | Wholesale & retail | 2015 |