| Grand Prix Masters Racing Limited | Administrative & support | 1998 |
| Grand Scheme Media Limited | Administrative & support | 2012 |
| Granite CFO Services Ltd | Professional & scientific | 2024 |
| Gravity Consulting Engineers Holdings Limited | Financial services | 2021 |
| Gravity Consulting Engineers Ltd | Professional & scientific | 2009 |
| GRD Film Services Ltd | Information & communication | 2016 |
| Greatdaze Limited | Professional & scientific | 2007 |
| Greater London IT Solutions Limited | Information & communication | 2014 |
| Green & White Catering Limited | Hospitality | 2013 |
| Green Jersey Limited | Wholesale & retail | 2008 |
| Green Park Investments LLP | | 2015 |
| Green Path Holdings Ltd | Professional & scientific | 2025 |
| Green Vehicle Solutions Group Ltd | Construction | 2023 |
| Green Voltage Ltd | Administrative & support | 2018 |
| Greenacre Financial Services Limited | Financial services | 2016 |
| Greenacre Property Services Limited | Real estate | 2019 |
| Greenfield Golfing Ltd | Manufacturing | 2024 |
| Greengage Development Corporation Limited | Professional & scientific | 1990 |
| Greenshoots Developments Limited | Construction | 2007 |
| Greenside Security Limited | Administrative & support | 2011 |
| Greenways Court Management Company Limited | Hospitality | 1989 |
| Greenyard Prepared UK Limited | Wholesale & retail | 1991 |
| Greywalls Holiday Lets Ltd | Real estate | 2024 |
| Greywalls Property Ltd | Real estate | 2017 |
| Griffin Park Capital Limited | Professional & scientific | 2020 |
| Griffiths Global Limited | Professional & scientific | 2018 |
| GRIT13 Limited | Arts & recreation | 2024 |
| Grove House Energy Consultants Limited | Construction | 2014 |
| GTD Marine Limited | Professional & scientific | 2025 |
| Guinot-Mary Cohr UK Limited | Wholesale & retail | 1972 |
| GW Real Estate Ltd | Real estate | 2022 |
| H 22 Limited | Real estate | 2001 |
| H22 Delta Limited | Real estate | 2006 |
| H22 Donlin Ltd | Real estate | 1990 |
| H22 Investments Limited | Real estate | 2005 |
| H22 Wimbledon Ltd | Real estate | 2005 |
| Haaf Limited | Information & communication | 2017 |
| Haaf Properties Ltd | Real estate | 2022 |
| Hachimann Limited | Wholesale & retail | 2020 |
| Haining Road Limited | Extraterritorial | 2004 |
| Hair by Harley Limited | Other services | 2022 |
| Hall Taylor & Co Law Ltd | Professional & scientific | 2018 |
| Hamad Yasir Ltd | Wholesale & retail | 2025 |
| Hamblemount Limited | Hospitality | 1982 |
| Hamlet International Trading Limited | Administrative & support | 2000 |
| Hampton Court Associates Financial Services LLP | | 2001 |
| Hanbury Hedgehog Limited | Professional & scientific | 2023 |
| Hancock Facilities Limited | Real estate | 2019 |
| Handel Pianos Limited | Wholesale & retail | 1995 |
| Handpicked Health Ltd | Wholesale & retail | 2024 |
| Hanol Limited | Professional & scientific | 2010 |
| Hanover Projects Limited | Wholesale & retail | 2025 |
| Hans & Alfred Ltd | Real estate | 2025 |
| Hans Property Limited | Real estate | 2022 |
| Hansco Ltd | Information & communication | 2023 |
| Hanson Builders Limited | Construction | 2004 |
| Happy Days Nursery (Broadmeadow) Limited | Health & social care | 2004 |
| Harbpharma Limited | Health & social care | 2017 |
| Harlequin Bespoke Apparel Limited | Wholesale & retail | 2014 |
| Harlequin Brickwork Contracting Limited | Construction | 2017 |
| Harlequin Brickwork Limited | Construction | 2011 |
| Harlequin Brickwork Solutions Limited | Construction | 2022 |
| Harlequin Construction Solutions Limited | Construction | 2021 |
| Harlequin Scaffolding Solutions Ltd | Construction | 2018 |
| Harley Street Aestheticians Ltd | Other services | 2023 |
| Harmony Property Support Ltd | Administrative & support | 2023 |
| Harper Gigi Property Holdings Limited | Construction | 2025 |
| Harrington Shaw Limited | Administrative & support | 2017 |
| Harris Cars Limited | Wholesale & retail | 1981 |
| Harris Estimating Limited | Professional & scientific | 2025 |
| Harrison & Partners Limited | Professional & scientific | 2002 |
| Harry Elsham Limited | Information & communication | 2026 |
| Harshad Limited | Wholesale & retail | 1998 |
| Harvey and Leech Limited | Real estate | 1949 |
| Hatch Mansfield Cellars Limited | Wholesale & retail | 2010 |
| Hatch, Mansfield Agencies Limited | Wholesale & retail | 1994 |
| Havana Healthcare Ltd | Administrative & support | 2026 |
| Hawks & Partners Limited | Extraterritorial | 2023 |
| Hawks Estate Agency Limited | Real estate | 2023 |
| Hawks Estate Agents Limited | Real estate | 2026 |
| Hawks Holdings Limited | Financial services | 2023 |
| Haxton Services Ltd | Construction | 2025 |
| Hazelwood Estates (Lcra) Limited | Extraterritorial | 2003 |
| Hazelwood Estates Holdings Limited | Construction | 1998 |
| Hcam Asset Management UK Limited | Financial services | 2007 |
| HCT Group Holdings Ltd | Construction | 2022 |
| HCT Homes Ltd | Construction | 2013 |
| HDS Psychological Services Limited | Health & social care | 2014 |
| Head Light Limited | Information & communication | 2004 |
| Headmapper Limited | Administrative & support | 2015 |
| Healthaxon Group Limited | Financial services | 2023 |
| Healthboxhr Ltd | Information & communication | 2024 |
| Healthy Life Media Ltd | Professional & scientific | 2019 |
| Heart of the Circle Ltd | Health & social care | 2017 |
| Heartlands (Cawston) Limited | Real estate | 2025 |
| Heatherlands Management Company Limited | Extraterritorial | 1990 |
| Heathfield School | Education | 1955 |
| Heathlands Park Management Company Limited | Households | 1988 |
| Heaven Collective Ltd | Wholesale & retail | 2025 |
| Hebas Ascot Limited | Construction | 2005 |