| Groomon Europe Limited | Wholesale & retail | 2025 |
| Grosvenor Associates (U.K.) Limited | Real estate | 1990 |
| Grosvenor Financial Asset Management Limited | Financial services | 2003 |
| Grouse Advisory Limited | Financial services | 2010 |
| Grove Lodge Limited | Households | 1980 |
| Grovel Multilayer Farms Limited | Agriculture & fishing | 2024 |
| Grovia Ventures Limited | Financial services | 2025 |
| Grow Management (UK) Limited | Real estate | 2016 |
| Growing Square Limited | Arts & recreation | 2018 |
| Grummett Limited | Professional & scientific | 2019 |
| GS Advisors Limited | Professional & scientific | 2013 |
| GS Books Limited | Professional & scientific | 2008 |
| GS Build & Design Ltd | Construction | 2019 |
| GS Consulting Group Limited | Professional & scientific | 2016 |
| GS1 (SPV) Ltd | Construction | 2025 |
| Gseh Ltd | Transport & logistics | 2018 |
| GSI Electrical Limited | Construction | 2017 |
| GSJ Investments LLP | | 2004 |
| GSS Piling Ltd. | Construction | 2006 |
| GT Aerospace Ltd | Administrative & support | 2025 |
| GT Films Limited | Financial services | 2023 |
| GTA Building Services Limited | Construction | 2016 |
| GTB Global Ltd | Wholesale & retail | 2017 |
| Gttr Limited | Other services | 2024 |
| Guia Construction Ltd | Construction | 2013 |
| Guiding Light Assembly (GLA), UK | Other services | 2010 |
| Gulf Facilities LLP | | 2016 |
| Gulf Premium Services Limited | Transport & logistics | 2025 |
| Gullwing Hospitality Ltd | Professional & scientific | 2020 |
| GUT Health UK Ltd | Health & social care | 2026 |
| Gutenberg Print Ltd | Wholesale & retail | 2026 |
| Guys Grooming Lounge Limited | Other services | 2025 |
| GVK Tech Limited | Information & communication | 2015 |
| Gvozdan Limited | Health & social care | 2016 |
| GVS Enterprises Limited | Real estate | 2023 |
| Gwangsan Ltd | Hospitality | 2018 |
| GZ Construction London Ltd | Construction | 2019 |
| H & R Management London Limited | Real estate | 2018 |
| H & S Polythene Limited | Wholesale & retail | 1982 |
| H & Z (Bloxhall Road) Limited | Real estate | 2021 |
| H & Z (Priory) Limited | Real estate | 2023 |
| H & Z (Wanstead) Limited | Real estate | 2019 |
| H & Z Investments (London) Limited | Real estate | 2018 |
| H Firkins & Sons Limited | Administrative & support | 2013 |
| H H Maintenance Limited | Construction | 2026 |
| H Jacobs Limited | Professional & scientific | 2023 |
| H K Therapy Limited | Health & social care | 2020 |
| H V Albrow Ltd | Wholesale & retail | 2011 |
| H&Mc Solutions Ltd | Health & social care | 2016 |
| H-Vision Contractors Ltd | Construction | 2024 |
| H.H.Khan of Kalat (Private Office) Ltd | Financial services | 2023 |
| H.I.Salon Systems Ltd | Wholesale & retail | 2025 |
| H2 Powerpod (Research) Ltd | Extraterritorial | 2009 |
| H2327 Limited | Real estate | 2010 |
| H2T Health Ltd | Health & social care | 2026 |
| HA Commercial Holdings Ltd | Financial services | 2025 |
| HA Commercial Properties Ltd | Real estate | 2025 |
| Haastrup Financial Services Limited | Professional & scientific | 2014 |
| Haberdashers Elstree Schools Trading Limited | Real estate | 1995 |
| Habib Sudic Phillips LLP | | 2012 |
| Habitual Limited | Information & communication | 2012 |
| Hailsham Coffee Ltd | Hospitality | 2022 |
| Hailsham Consulting Ltd | Wholesale & retail | 2023 |
| Hair About Limited | Other services | 2019 |
| Hair by Radoushka Limited | Other services | 2024 |
| Hairport Barber Prestatyn Ltd | Other services | 2024 |
| Hajiz Spice Ltd | Hospitality | 2026 |
| Hakim Clinic Ltd | Health & social care | 2009 |
| Hakimi Health Care Limited | Health & social care | 2018 |
| Hakimi UK LLP | | 2014 |
| Hala Hassan Limited | Education | 2014 |
| Hala Street Food Limited | Hospitality | 2024 |
| Hala Zidan Ltd | Education | 2023 |
| Halahmy Properties LLP | | 2016 |
| Halerose Limited | Professional & scientific | 2020 |
| Halestrong Limited | Administrative & support | 1995 |
| Halesworth Court RTM Company Limited | Households | 2019 |
| Hall Court Management Company Limited | Households | 1984 |
| Hall Gate Management Company Limited | Households | 1966 |
| Hall Road (Rochford) Management Company Limited | Real estate | 2015 |
| Hallie ANN Limited | Hospitality | 2026 |
| Hallmark Property Investments CIC | Health & social care | 2022 |
| Hallsville Management Company Limited | Real estate | 2013 |
| Hallsville Quarter (Phase 1) Residents Company Limited | Real estate | 2012 |
| Hallsville Quarter (Phase 2) Residents Company Limited | Extraterritorial | 2014 |
| Halo House Buyers LLP | | 2019 |
| Halo IT Limited | Administrative & support | 2014 |
| Halo Wines Ltd | Wholesale & retail | 2023 |
| Hamesman Limited | Professional & scientific | 2011 |
| Hamilton Development Group (Hendon) Ltd | Construction | 2018 |
| Hamilton Development Group (Witchford) Limited | Construction | 2024 |
| Hamilton Development Group Limited | Real estate | 2013 |
| Hamilton Development LLP | | 2011 |
| Hamlane Limited | Real estate | 2024 |
| Hamley Consulting Limited | Professional & scientific | 2000 |
| Hamley Property (6) Limited | Construction | 2014 |
| Hamley Property Developments Ltd | Real estate | 2016 |
| Hammam Havlu Limited | Manufacturing | 2015 |
| Hammer House Investment Limited | Real estate | 2024 |
| Hammerhand Ltd | Arts & recreation | 2025 |