| Harris Finance (Grays) Limited | Financial services | 1982 |
| Harris Holdings (Grays) Limited | Professional & scientific | 1973 |
| Harris Travel Agency Limited | Administrative & support | 1970 |
| Harris' Properties (Grays) Limited | Real estate | 1963 |
| Harrisons Wharf (Purfleet) Limited | Real estate | 1998 |
| Harrogate Holdings Limited | Construction | 2019 |
| Harry Trezo Cart Ltd | Wholesale & retail | 2025 |
| Hartford Ventures Ltd | | 1996 |
| Harvestcalc Limited | Information & communication | 2025 |
| Harvesting Potential Limited | Information & communication | 2006 |
| Harvey & Little Building Services Limited | Construction | 2003 |
| Harvey Barber Shop Ltd | Other services | 2025 |
| Harvey Brown Limited | Manufacturing | 1998 |
| Harwoods of Essex Limited | Wholesale & retail | 1973 |
| HAS Living Ltd | Real estate | 2023 |
| Hassan Healthtech Ltd | Information & communication | 2024 |
| Hassan Investment Group Ltd | Financial services | 2024 |
| Hassan Investment Two Limited | Real estate | 2023 |
| Hassan Mart 77860 Limited | Wholesale & retail | 2026 |
| Hastingwood Court (Trinity Close) Management Limited | Real estate | 1987 |
| Hatton Property Services Ltd | Real estate | 2022 |
| Hattotuwa Limited | Health & social care | 2006 |
| Haulmark Transport Limited | Information & communication | 1987 |
| Havering Building Specialists Limited | Construction | 1968 |
| Havering Care Homes Ltd | Health & social care | 1998 |
| Havering Christian Bookshop Limited | Wholesale & retail | 1978 |
| Havering Sanitary Engineers Limited | Wholesale & retail | 1973 |
| Hawk Security Group Ltd | Administrative & support | 2016 |
| HAY Bagri Ltd | Hospitality | 2019 |
| Haymacc Limited | Construction | 2025 |
| Hayward & Co (Estate Agents) Limited | Professional & scientific | 1995 |
| Hayward Estates Ltd | Real estate | 2024 |
| Hazana Care Ltd | Health & social care | 2024 |
| Hazels Catering Services Ltd | Hospitality | 2025 |
| Hazin Retail Ltd | Wholesale & retail | 2023 |
| HB Cables and Components Limited | Wholesale & retail | 2006 |
| Hbib Limited | Financial services | 2014 |
| Hbkb Enterprise Ltd | Professional & scientific | 2021 |
| HCL Accountancy Limited | Professional & scientific | 2007 |
| HCS Office Cleaning & Facilities Management Limited | Administrative & support | 2006 |
| HD Window Films Ltd | Wholesale & retail | 2024 |
| HDC Surfacing & Construction Ltd | Construction | 2024 |
| HDS Consulting Limited | Administrative & support | 2006 |
| Headley Chase Management Company Limited | Households | 1991 |
| Headstart Limited | Education | 2010 |
| Heal Dove Limited | Health & social care | 2025 |
| Heal House Limited | Health & social care | 2022 |
| Healey Tool Hire & Sales Limited | Wholesale & retail | 1986 |
| Healing Young Hearts Ltd | Education | 2024 |
| Health & Safety Risk Management Limited | Construction | 2004 |
| Health Psychology Management Organisation Services | Professional & scientific | 2006 |
| HEALTH4ALLSEASONS Ltd | Health & social care | 2016 |
| Healthfield Medical Services Limited | Health & social care | 2022 |
| Healthline (UK) Limited | | 1983 |
| Healthrive Solutions Ltd | Health & social care | 2025 |
| Healthy Life Essex C.I.C | Information & communication | 2005 |
| Heat & EAT Limited | Real estate | 2001 |
| Heathfields (Hethersett) Management Company Limited | Households | 2014 |
| Heating Warehouse Limited | Wholesale & retail | 1983 |
| Heatup Building & Plumbing Limited | Construction | 2024 |
| Heavenly Hot Dogs Limited | Hospitality | 2003 |
| Hebii's Limited | Wholesale & retail | 2025 |
| Heelis Construction Limited | Administrative & support | 2017 |
| Heheals Pharmaceutical Services Ltd | Health & social care | 1998 |
| Helal & Sons Limited | Real estate | 2006 |
| Helal Sadat Ltd | Wholesale & retail | 2025 |
| Helen Harrison & Company Limited | Administrative & support | 1993 |
| Helena Howard Limited | | 1983 |
| Helios Capital Partners Limited | Financial services | 2025 |
| Hellenus Line Agencies Limited | | 1983 |
| Helm Wellbeing Limited | Other services | 2026 |
| Helmpose Limited | Wholesale & retail | 1981 |
| Helpcards Holdings Limited | Financial services | 1995 |
| Helpcards Limited | Wholesale & retail | 1978 |
| Henbuk Consulting Limited | Health & social care | 2004 |
| Henlat UK Limited | Transport & logistics | 2004 |
| Henry Fairley & SON Limited | Agriculture & fishing | 1997 |
| Henshall Property Investors Limited | Real estate | 2023 |
| Hermess Global Ltd | Wholesale & retail | 2026 |
| Herongate Eagle Way NO.2 Management Company Limited | Real estate | 2001 |
| Heronsgate Beverages Ltd | Wholesale & retail | 2025 |
| Herts & Essex Alarms Ltd | Other services | 2002 |
| Herts Consulting Limited | Other services | 2025 |
| Herve Engineering Limited | Manufacturing | 1919 |
| Hetra Media Limited | Information & communication | 2002 |
| HEW Groceries Ltd | Wholesale & retail | 2019 |
| Hewett Professional Services Ltd | Professional & scientific | 2025 |
| HEX Solutions Limited | Information & communication | 2007 |
| Hexathon Group Limited | Real estate | 2025 |
| HEY Drivers Ltd | Administrative & support | 2026 |
| Heybridge Consultancy Services Ltd | Information & communication | 2006 |
| Heyworth Builders Ltd | Construction | 2006 |
| Hezibah Logistics Ltd | Transport & logistics | 2013 |
| Hg&Co Ltd | Manufacturing | 1984 |
| Hgul Store Ltd | Wholesale & retail | 2026 |
| Hi-Tech Seven Star Ltd | Wholesale & retail | 2025 |
| Hibalizay Business Solutions Ltd | Wholesale & retail | 2023 |
| Hibba Properties Limited | Real estate | 2001 |
| Hickerydock Limited | Hospitality | 2016 |
| Hicks Electrical Limited | Construction | 2006 |