| HAQ Solutions Group Limited | Administrative & support | 2026 |
| Haqqai Ltd | Information & communication | 2025 |
| Harbour Link Limited | Real estate | 2022 |
| Hard Science Ltd | Professional & scientific | 2025 |
| Harder Holdings Ltd | Real estate | 2021 |
| Harding Developments Ltd | Real estate | 2025 |
| Hardisty Properties Limited | Financial services | 2025 |
| Hardprog Ltd | Professional & scientific | 2012 |
| Hardwick Hewitt Limited | Real estate | 1979 |
| Harecroft Consultants Ltd | Professional & scientific | 2026 |
| Harewood House (Whiting Street) Management Limited | Households | 1992 |
| Hari Corporation Ltd | Real estate | 2025 |
| Hariel Ltd | Wholesale & retail | 2025 |
| Harkness Kennett Ltd | Professional & scientific | 2002 |
| Harkourts Trading Ltd | Wholesale & retail | 2025 |
| Harlington Straker Ltd | Hospitality | 2024 |
| Harlow Carr Ltd | Real estate | 2026 |
| Harlyy Software Ltd | Professional & scientific | 2023 |
| Harmless Packaging Limited | Extraterritorial | 2016 |
| Harmoniease Ltd | Health & social care | 2025 |
| Harmony Business Consultants Ltd | Transport & logistics | 2012 |
| Harpers Helping Hands Ltd | Construction | 2023 |
| Harrar Developments Ltd | Construction | 2026 |
| Harriets Cafe Tearooms Limited | Hospitality | 1994 |
| Harrington Morgan Limited | Education | 2002 |
| Harris & Hill Limited | Manufacturing | 2025 |
| Harris Brook Limited | Financial services | 2009 |
| Harris Building Services Ltd | Construction | 2025 |
| Harris House Property Limited | Real estate | 2023 |
| Harrison Gill Consultants UK Limited | Health & social care | 2018 |
| Harrman Solutions Limited | Professional & scientific | 2025 |
| Harrop Allen Ltd | Financial services | 2026 |
| Harry's Hardware Ltd | Wholesale & retail | 2019 |
| Harrys Butchers Limited | Wholesale & retail | 2015 |
| Hartes Foundary Ltd | Manufacturing | 2025 |
| Hartewell Homecare Limited | Administrative & support | 2023 |
| Hartwell Homes Ltd | Real estate | 2025 |
| Harun Jamil Trading Ltd | Wholesale & retail | 2025 |
| Harvey Management Ltd | Administrative & support | 2016 |
| Harvis Meadow Limited | Professional & scientific | 2026 |
| Harwood Nash Trading Limited | Wholesale & retail | 2020 |
| HAS7 Consulting Limited | Professional & scientific | 2026 |
| Hasan Real Estate Ltd | Real estate | 2024 |
| Hashem Network Limited | Information & communication | 2026 |
| Hasinc Ltd | Information & communication | 2026 |
| Haspel & Co LLP | | 2014 |
| Hassan AL Hamed Trading Limited | Wholesale & retail | 2025 |
| Hatfield's Nursing Services Ltd | Health & social care | 2023 |
| Hathor Ltd | Arts & recreation | 2026 |
| Hatter Street Studio Limited | Arts & recreation | 2026 |
| Hauldrive Ltd | Information & communication | 2025 |
| Hauser Property Limited | Real estate | 2020 |
| Haven Snacks Ltd | Hospitality | 2024 |
| Havenfield Studio Ltd | Wholesale & retail | 2025 |
| Havenlet Properties Limited | Real estate | 2025 |
| Haverfield Clarks Limited | Professional & scientific | 2017 |
| Haverhill Enterprise Limited | Administrative & support | 1994 |
| Haverhill Investments Limited | Real estate | 2010 |
| Havik Ltd | Wholesale & retail | 2022 |
| Hawk Way Management Co Ltd | Extraterritorial | 2005 |
| Hawkdon Ltd | Professional & scientific | 2021 |
| Hawker Warehouse Ltd | Hospitality | 2022 |
| Hawkins Forestry Limited | Agriculture & fishing | 2018 |
| Hawkins Organic Limited | Professional & scientific | 2014 |
| Hawsha Ltd | Information & communication | 2026 |
| Hawthorns Real Estate Limited | Real estate | 2026 |
| Hawtree Management Ltd | Other services | 2024 |
| Hawwke Limited | Manufacturing | 2021 |
| Haybury Build Limited | Real estate | 2021 |
| Hayden Brinkley Ltd | Professional & scientific | 2019 |
| Hayesbridge Ltd | Information & communication | 2026 |
| Hayles Holdings Limited | Financial services | 2025 |
| Hayles Security Group Limited | Administrative & support | 2025 |
| Haylohub Ltd | Information & communication | 2024 |
| Haynes Brothers Analysis & Design Limited | Information & communication | 2010 |
| Haynes Property Solutions Limited | Real estate | 2024 |
| Hayrea Limited | Wholesale & retail | 2025 |
| Hayward Property Holdings Ltd | Real estate | 2025 |
| Hazaraglobaltraders Ltd | Wholesale & retail | 2025 |
| Hazard and Hygiene Remediation Ltd | Administrative & support | 2025 |
| Hazari Consultant LLP | | 2016 |
| Hazarussell Ltd | Professional & scientific | 2023 |
| Hazeldon Developments Ltd | Construction | 2025 |
| Hazells & Co (BSE) Limited | Real estate | 2007 |
| HB Construction Management Ltd | Professional & scientific | 2025 |
| HC1 Finance Ltd | Real estate | 2022 |
| HCB Projects Ltd | Manufacturing | 2019 |
| HD Total Services Ltd | Construction | 2023 |
| Hdhq Investments Ltd | Information & communication | 2018 |
| Hdsgreentech Limited | Professional & scientific | 2014 |
| HDV Media Ltd | Arts & recreation | 2024 |
| Headbridge Associates Limited | Professional & scientific | 2016 |
| Headrose Barbering Limited | Other services | 2017 |
| Headstart Foundation | Extraterritorial | 2025 |
| Healanche Ltd | Health & social care | 2025 |
| Healbloom Life Ltd | Wholesale & retail | 2025 |
| Health Estates Ltd | Health & social care | 2019 |
| Health FLO Limited | Public administration | 2024 |
| Health Hub Operations Ltd | Arts & recreation | 2026 |
| Health Safety Training Ltd | Education | 2016 |