| GUS Davies Limited | Professional & scientific | 2001 |
| GVZ Investments Limited | Financial services | 2022 |
| GWS Repairs Ltd | Wholesale & retail | 2020 |
| Gwynne TV & Electrical Services Limited | Other services | 2004 |
| GXT International Consulting Ltd | Information & communication | 2025 |
| GYE Nyame Limited | Extraterritorial | 1998 |
| GZ Holdings Ltd | Financial services | 2025 |
| H & S Powder Coating Limited | Construction | 2008 |
| H and E Boutique Limited | Wholesale & retail | 2024 |
| H Barber Billercay Ltd | Other services | 2026 |
| H G Tyler & SON Limited | Construction | 2003 |
| H L (Europe) Limited | Manufacturing | 2004 |
| H M Legal Consultants Limited | Professional & scientific | 2007 |
| H Pong Limited | Administrative & support | 2022 |
| H S Asset Management Limited | Manufacturing | 2006 |
| H Tyres Hub Ltd | Wholesale & retail | 2026 |
| H Wright Trading Ltd | Financial services | 2024 |
| H&B Group Ltd | Wholesale & retail | 2025 |
| H. & E. Insurance Brokers Estate Agents Limited | | 1968 |
| H. Aspirations Limited | Real estate | 2002 |
| H. Gunton Limited | Wholesale & retail | 1965 |
| H. P. Carpets Limited | | 1983 |
| H. P. P. Freight Services Limited | Information & communication | 1985 |
| H.D. Cobbald and Sons Limited | Agriculture & fishing | 1948 |
| H.H.Keys Estates Limited | Real estate | 1957 |
| H.M. Lingard Limited | Construction | 1987 |
| H.P. Cooper (Farms) Limited | Agriculture & fishing | 1958 |
| H.S. Bassi and Sons (U.K.) Limited | Real estate | 1980 |
| H.T. Renovations Limited | Construction | 2004 |
| H.W.Wilson Limited | Construction | 2000 |
| H2 Business Communication Limited | Information & communication | 2003 |
| HA Merchant Ltd | Wholesale & retail | 2024 |
| HA Planning & Surveying Ltd | Professional & scientific | 2026 |
| Habeza Solutions Limited | Health & social care | 2026 |
| Habibidigi Ltd | Information & communication | 2026 |
| Habitat Nexus Limited | Wholesale & retail | 2026 |
| Habits Medical Ltd | Health & social care | 2026 |
| Hack and Master Ltd | Information & communication | 2025 |
| Hacton Holdings Ltd | Financial services | 2019 |
| Hacton House(Upminster)Limited | Construction | 1959 |
| Hafiz Ammar Mushtaq Ltd | Wholesale & retail | 2025 |
| Hagon Products Limited | Manufacturing | 1974 |
| Hainault General Store Limited | Wholesale & retail | 2026 |
| Hair Bian Ltd | Other services | 2018 |
| Hair Media | | 1998 |
| HAK247 Homes Limited | Real estate | 2023 |
| Hakt Property Ltd | Real estate | 2020 |
| Halal Foods (UK) Limited | Hospitality | 2014 |
| Halbie Homes Ltd | Real estate | 2022 |
| Haldime Ltd | Professional & scientific | 2005 |
| Hales Commercial Limited | Wholesale & retail | 2007 |
| Halif ALI Shah Ltd | Wholesale & retail | 2025 |
| Hallingbury Marina Limited | Professional & scientific | 1997 |
| Hallsford Estates Limited | Administrative & support | 1995 |
| Halstead Plating Services Limited | Manufacturing | 1980 |
| Halstead Tyre & Exhaust Centre Limited | Wholesale & retail | 2005 |
| Hamas Ventures Ltd | Wholesale & retail | 2026 |
| Hameed & Sons Global Ltd | Wholesale & retail | 2025 |
| Hamidiye Community Care Limited | Education | 2026 |
| Hamlab Investments UK Limited | Construction | 2014 |
| Hammered Ltd. | Administrative & support | 2005 |
| Hampton Wells Limited | Extraterritorial | 1996 |
| Hamptonshaw Ltd | Construction | 1995 |
| Hamstring Ltd | Professional & scientific | 2006 |
| Hamzacrafts Ltd | Wholesale & retail | 2026 |
| Hanarin Ltd | Information & communication | 2023 |
| Hand in Hand Group Limited | Professional & scientific | 2003 |
| Handy Bandy Limited | Wholesale & retail | 2025 |
| Hanover Builders (Essex) Limited | Construction | 1997 |
| Happy Buddha Clean Ltd | Other services | 2021 |
| Happy Nails and Beauty Limited | Other services | 2018 |
| Haramain Tour EU Ltd | Administrative & support | 2025 |
| Harbfar Ltd | Wholesale & retail | 2024 |
| Harding & Sayer Limited | | 1990 |
| Hardingflow Ltd | Water & waste | 2026 |
| Hardy Engineering Limited | Manufacturing | 2000 |
| Hardy Media Limited | Administrative & support | 2008 |
| Hardy Publications Limited | Information & communication | 2005 |
| Harewood Management Limited | Professional & scientific | 2006 |
| Harlequin Gymnastics Club Limited | Education | 2007 |
| Harley Place Ltd | Hospitality | 2000 |
| Harley Reed (UK) Limited | Administrative & support | 1996 |
| Harley Street Online Doctors Limited | Health & social care | 2005 |
| Harlow Chemical Company Limited | Financial services | 1963 |
| Harlow Coach Works Limited | Wholesale & retail | 1963 |
| Harmonia Living Ltd | Households | 2025 |
| Harmonic Operations Limited | Information & communication | 2025 |
| Harmony Blinds (Rayleigh) Limited | Wholesale & retail | 2002 |
| Harmony Prints Limited | Wholesale & retail | 1986 |
| Harold Webb Motors Limited | Real estate | 1946 |
| Haroon Empire Limited | Wholesale & retail | 2026 |
| Haroon Mart Ltd | Wholesale & retail | 2026 |
| Haroonz Mart Ltd | Wholesale & retail | 2026 |
| Harper & Eede,Limited | Extraterritorial | 1933 |
| Harrington GAS Services Limited | Other services | 2006 |
| Harris Commercial (LEA Valley) Limited | Wholesale & retail | 1993 |
| Harris Commercial Coachworks Limited | Wholesale & retail | 1992 |
| Harris Commercial Repairs Limited | Wholesale & retail | 1974 |
| Harris Commercial Sales Limited | Wholesale & retail | 1976 |
| Harris Coorperation Limited | Construction | 2014 |