| Gobig Digital Ltd | Professional & scientific | 2019 |
| Goding Brothers Holdings Limited | Real estate | 2020 |
| Goetre Fawr Digital Limited | Administrative & support | 2025 |
| Goforit Global Limited | Other services | 2018 |
| Goksal Ltd | Hospitality | 2024 |
| Gold Gym Pro Limited | Arts & recreation | 2025 |
| Golden Dragon Chinese Restaurant Ltd | Hospitality | 2026 |
| Golden Sports Limited | Arts & recreation | 2011 |
| Golden Star Holdings Limited | Real estate | 2018 |
| Goliath Enderby Developments Ltd | Construction | 2015 |
| Goliath Technical Solutions Ltd | Administrative & support | 2018 |
| Goosehill Farm Limited | Wholesale & retail | 2024 |
| Gorilla Warfare Limited | Other services | 2015 |
| Goshin Karate and Fitness UK Limited | Education | 2021 |
| Gosling Yard Tempsford Management Company Limited | Households | 2020 |
| GPC Installations Ltd | Construction | 2019 |
| Gpmr Consulting Limited | Construction | 2013 |
| Grace Improvements Limited | Construction | 2015 |
| Graham Property Solutions Ltd | Construction | 2025 |
| Grand Union Limited | Manufacturing | 2021 |
| Grange Convenience Store Letchworth Ltd | Wholesale & retail | 2025 |
| Grange Wine Store Ltd | Wholesale & retail | 2025 |
| Grays Inn Yard Management Company Limited | Households | 2025 |
| Great Digital Company Limited | Professional & scientific | 2016 |
| Great Wall Chang Cheng Limited | Hospitality | 2022 |
| Greater Level Healthcare Services Ltd | Information & communication | 2026 |
| Green Care at Norton CIC | Agriculture & fishing | 2019 |
| Green Room Rentals Ltd | Real estate | 2025 |
| Green Vision Holding Ltd | Financial services | 2024 |
| Greendale Mews Management Company Limited | Households | 1989 |
| Greendrift Wills & Estates Ltd | Professional & scientific | 2021 |
| Greenery UK Limited | Wholesale & retail | 1969 |
| Greenman Homes Limited | Real estate | 2013 |
| Greenwich Partnership LLP | | 2011 |
| Greenwoods Investments Ltd | Real estate | 2022 |
| Gregory, Martin & Lazenby Limited | Other services | 2015 |
| Grey Goose Leadership Ltd | Professional & scientific | 2024 |
| Greystone Buildings Ltd | Administrative & support | 2017 |
| Greystone Engineering Ltd | Administrative & support | 2016 |
| GRM IT Limited | Information & communication | 2019 |
| Grove Court Maintenance Company (Arlesey) Limited | Real estate | 1975 |
| Grove House Health & Wellbeing Limited | Health & social care | 2013 |
| Grumpygrip Limited | Information & communication | 2002 |
| GS Financial Management Solutions Limited | Wholesale & retail | 2010 |
| GS& Grewalz Ltd | Transport & logistics | 2024 |
| Guaranteed Niceness Ltd | Manufacturing | 2016 |
| Guney IT Limited | Information & communication | 2015 |
| Guttikonda Properties Ltd | Real estate | 2024 |
| GW Lifts Limited | Manufacturing | 2022 |
| GXP Consultancy Limited | Professional & scientific | 2022 |
| H Nixon Consulting Ltd | Professional & scientific | 2020 |
| Haak Properties Ltd | Real estate | 2021 |
| Hadham Enterprises Limited | Administrative & support | 2015 |
| Hall Network Services Limited | Construction | 2001 |
| Halyard Properties Limited | Real estate | 1997 |
| Hambidge Consultancy Limited | Construction | 2007 |
| Hampden Close Residents Association Limited | Households | 2000 |
| Handclap Limited | Information & communication | 2025 |
| Hanlo Ltd | Professional & scientific | 2018 |
| Hanscombe Meadows Management Company Limited | Households | 2018 |
| Happy Fitness Nutrition & Wellness Limited | Arts & recreation | 2025 |
| Happy Shacks Limited | Construction | 2019 |
| Harbell Limited | Professional & scientific | 2016 |
| Harbour Private Client Ltd | Administrative & support | 2025 |
| Harcross Specialist Contractors Limited | Construction | 1999 |
| Hardwicke Investments Limited | Professional & scientific | 2007 |
| Hare Analytical Ltd | Professional & scientific | 2020 |
| Hari Prerit Ltd | Real estate | 2021 |
| Hari Rakshit Ltd | Real estate | 2025 |
| Haridarshan Ltd | Wholesale & retail | 2018 |
| Harley Street Hospital Limited | Health & social care | 2018 |
| Harlington Investors Limited | Real estate | 2021 |
| Hart Employment Services Limited | Education | 1994 |
| Harvest Court Residents Limited | Households | 1999 |
| Hatton Road (Bedfont) Management Company Limited | Households | 1989 |
| Havell House Limited | Construction | 2021 |
| Hawk House Consulting Ltd | Professional & scientific | 2020 |
| Hawkins Properties Limited | Construction | 1961 |
| Hayer and Sons Property Developments Limited | Real estate | 2022 |
| Hayer Property Developments Limited | Real estate | 2021 |
| Hayer Ventures Limited | Transport & logistics | 2014 |
| Haze Cleansing Services Limited | Water & waste | 2019 |
| HBC Property Group Ltd | Construction | 2025 |
| Health & Independent Living Support Limited | Hospitality | 2023 |
| Healthadvance Ltd | Health & social care | 2017 |
| Hearts of Howells Ltd | Wholesale & retail | 2025 |
| Hedger Way Ltd | Administrative & support | 2016 |
| Helen Cass Limited | Information & communication | 2015 |
| Hello Change Ltd | Other services | 2025 |
| Henderson and Partners (UK) Limited | Professional & scientific | 2015 |
| Henderson Curle Asset Management Limited | Real estate | 2018 |
| Henry Smith Consulting Limited | Professional & scientific | 2024 |
| Heritage Bricks Ltd | Financial services | 2026 |
| Hermitage Road Freehold Limited | Real estate | 2024 |
| Hermitage Road Ltd | Real estate | 2024 |
| Hermitage Sheet Metal Limited | Extraterritorial | 2013 |
| Heronwick Ltd | Wholesale & retail | 2026 |
| Hertford Television Service Limited | Manufacturing | 2013 |
| Hertfordshire Couriers Ltd | Transport & logistics | 2012 |
| Hertfordshire Landscape Solutions Limited | Construction | 2009 |