| Green Tomatas Ltd | Wholesale & retail | 2020 |
| Green Ventilation Ltd | Wholesale & retail | 2025 |
| Greenday Events Security Limited | Financial services | 2024 |
| Greenspace Plumbing and Heating Ltd | Construction | 2021 |
| Greg Haulage Ltd | Construction | 2018 |
| Griffin Upholstery Limited | Other services | 2020 |
| Grip Active Limited | Wholesale & retail | 2016 |
| Gripstone Tyre Centre Limited | Wholesale & retail | 2025 |
| Grochib Services Limited | Other services | 2016 |
| Grow Naturally Ltd | Wholesale & retail | 2024 |
| Gruppo Ltd | Real estate | 2022 |
| GS Advising Limited | Professional & scientific | 2022 |
| GSD Consultancy Ltd | Professional & scientific | 2022 |
| GSS Security Services Ltd | Administrative & support | 2013 |
| Gsts Properties LLP | | 2024 |
| GT Cafe & Pizza Shop Ltd | Hospitality | 2026 |
| GT9 Contractors Ltd | Construction | 2021 |
| Guidance CIC | Other services | 2023 |
| Guiseppe Limited | Real estate | 2021 |
| Gulf Global Travel & Tours UK Ltd | Administrative & support | 2026 |
| Gumgumgames Ltd | Wholesale & retail | 2024 |
| Guten TAG Cars Ltd | Wholesale & retail | 2024 |
| Gutierrezcarter Ltd | Professional & scientific | 2025 |
| Gvcm Ltd | Health & social care | 2022 |
| GYA Consulting Limited | Information & communication | 2025 |
| H & M Autos Limited | Wholesale & retail | 2009 |
| H & M Food Limited | Wholesale & retail | 2012 |
| H&Dsandhu Ltd | Wholesale & retail | 2025 |
| H&M Transportation Ltd | Water & waste | 2023 |
| H&P (PVT) Limited | Other services | 2018 |
| H. Smith (Meat & Poultry) Limited | Wholesale & retail | 1997 |
| H. Smith Food Group PLC | Wholesale & retail | 1990 |
| H.O. Sari Property Ltd | Real estate | 2021 |
| H.S Bishop Limited | Other services | 2019 |
| H2OOH Ltd | Professional & scientific | 2025 |
| H2TERMINALS Limited | Energy | 2024 |
| HAA Health Ltd | Health & social care | 2025 |
| Haandi Roti Ltd | Hospitality | 2024 |
| Habiitat Hub Limited | Real estate | 2024 |
| Hadassah Healing Foundation UK | Extraterritorial | 2013 |
| Hafiz Consultants Ltd | Professional & scientific | 2023 |
| Hair Design Co. Ltd | Other services | 2025 |
| Hair From US Ltd | Other services | 2022 |
| Half Moon Ventures Limited | Information & communication | 2024 |
| Hambro Group Ltd | Financial services | 2020 |
| Hambro Holdings Limited | Real estate | 2017 |
| Hambro Residential Limited | Real estate | 2020 |
| Hambro Roofing Limited | Construction | 1997 |
| Hammondson Limited | Administrative & support | 2007 |
| Hampton Hick Ltd | Real estate | 2019 |
| Hand Craft Builders Ltd | Construction | 2023 |
| Hania Traders Ltd | Real estate | 2026 |
| Hannan Assets Limited | Real estate | 2020 |
| Hannifer Limited | Health & social care | 2024 |
| Happy Customers HC Ltd | Wholesale & retail | 2022 |
| Harbour Lights Properties Limited | Real estate | 2016 |
| Harding Property Development Ltd | Real estate | 2018 |
| Hardit Construction Ltd | Construction | 2021 |
| Harmanpreet Ahir (London) Limited | Professional & scientific | 2022 |
| Harmony and Care Limited | Health & social care | 2024 |
| HAS ER Property Limited | Real estate | 2023 |
| Hasani Group Ltd | Real estate | 2026 |
| Hashim Halal Meat Ltd | Wholesale & retail | 2025 |
| Hassbell Global Resource Limited | Construction | 2015 |
| HAT Enterprises Ltd | Professional & scientific | 2024 |
| Hatfield Logistics Ltd | Transport & logistics | 2018 |
| Hatigen Consulting Services Limited | Information & communication | 2020 |
| Havana Sales Limited | Wholesale & retail | 2023 |
| Havering Decorating Services Limited | Construction | 2021 |
| Hawksgrove Building & Maintenance Ltd | Construction | 2022 |
| Hayat Consultants Ltd | Administrative & support | 2025 |
| Hayati by Hayley Ltd | Other services | 2024 |
| HB Essex Ltd | Wholesale & retail | 2023 |
| HCC Limited | Construction | 2026 |
| Healthcare Choices Group Limited | Administrative & support | 2019 |
| Healthrite UK Limited | Wholesale & retail | 2019 |
| Healthy Eating Ltd | Hospitality | 2022 |
| Heans Property Ltd | Real estate | 2019 |
| Heat Engineering Limited | Construction | 2021 |
| Heather Jupp Limited | Health & social care | 2018 |
| HEAVEN8 Ltd | Wholesale & retail | 2013 |
| Heavy Business Group Ltd | Wholesale & retail | 2018 |
| Heigar Homes Limited | Construction | 2021 |
| Hellowork Consultants Limited | Administrative & support | 2024 |
| HELP2FINANCE Limited | Financial services | 2019 |
| HELP2INSURE Limited | Financial services | 2019 |
| HELP2RENT Property Management Ltd | Real estate | 2021 |
| Helux Market Group Limited | Wholesale & retail | 2009 |
| Hennis JOE Limited | Health & social care | 2020 |
| Henry Ceramic Tiling Limited | Construction | 2015 |
| Hephzibahnet Megabest Ltd | Wholesale & retail | 2020 |
| Here & There Cleaning Services Ltd | Administrative & support | 2018 |
| Heritage Housing Education and Advisory Hub CIC | Education | 2026 |
| Hexa Network Solutions Ltd | Information & communication | 2022 |
| Hexagon Lounge Ltd | Hospitality | 2025 |
| Heybridge News Aathira Ltd | Wholesale & retail | 2026 |
| HGC Drylining Ltd | Construction | 2023 |
| HHS Retails Ltd | Wholesale & retail | 2024 |
| Hi-Fly Travel Agency Ltd | Administrative & support | 2025 |
| Hi-Tek Projects Limited | Other services | 2019 |