| Hammock Cryogenic Engineering Limited | Construction | 2015 |
| Hamoan Wealth Management Ltd | Financial services | 2025 |
| Hampstead Garden Suburb Joinery & Glazing Ltd | Construction | 2016 |
| Hamzette Ltd | Transport & logistics | 2019 |
| HAN Block Ltd | Arts & recreation | 2023 |
| Hanaho Property Investments Ltd | Administrative & support | 2017 |
| Hanava Group Limited | Professional & scientific | 2019 |
| Hanava Properties Ltd | Real estate | 2021 |
| Hancroft Properties Limited | Real estate | 1998 |
| Handley Gardens (Lancaster Avenue) Block Management Company Limited | Households | 2022 |
| Handley Gardens Management CIC | Households | 2019 |
| Hani Builders Ltd | Construction | 2023 |
| Hanleco Limited | Administrative & support | 2024 |
| Hanley Investment Ltd | Real estate | 2021 |
| Hannah Spice Ltd | Arts & recreation | 2024 |
| Hanover Holdings (London) Limited | Real estate | 2021 |
| Hanover Property Investments (London) Limited | Real estate | 2016 |
| Hanover Property Management and Administration Limited | Real estate | 2011 |
| Hansler Limited | Administrative & support | 2025 |
| Hansol Properties Ltd | Real estate | 2025 |
| Hanwell Launderettes Limited | Real estate | 1955 |
| Happy Sunflower House Limited | Administrative & support | 2020 |
| Happy Tails Hampers Limited | Wholesale & retail | 2022 |
| Happy Tree (West Drayton) Ltd | Education | 2009 |
| Happy Tree Limited | Real estate | 2016 |
| Harcourt Developments & Investments (UK) Limited | Extraterritorial | 2007 |
| Harcourt Developments (UK) Limited | Construction | 1999 |
| Harcourt House Oxford Limited | Real estate | 2023 |
| Harcrest Ltd | Real estate | 2024 |
| Hards & Co Creative Limited | Professional & scientific | 2011 |
| Hardwicke Finance Ltd | Financial services | 2013 |
| Hardy Towers Limited | Arts & recreation | 2017 |
| Haria Management Ltd | Real estate | 2010 |
| Harkos Property Management Ltd | Real estate | 2000 |
| Harley City Clinic Limited | Health & social care | 2019 |
| Harley House Ltd | Health & social care | 2013 |
| Harley Street Practice Limited | Other services | 2012 |
| Harmony Dental Spa Ltd | Health & social care | 2016 |
| Harmur Ltd | Manufacturing | 2020 |
| Haroldston Ltd | Professional & scientific | 2010 |
| Haroon and Co Enterprises Limited | Health & social care | 2024 |
| Harp Electrical Engineering UK Ltd. | Construction | 2012 |
| Harris Services Limited | Professional & scientific | 2020 |
| Harrow Premier Limited | Health & social care | 2015 |
| Harry Dixon Studio Ltd | Information & communication | 2021 |
| Harry's Propertyrental Ltd | Real estate | 2024 |
| Hartbest Limited | Professional & scientific | 2021 |
| Hartforde Dental Centre Limited | Health & social care | 2007 |
| Hartland Point Limited | Real estate | 2013 |
| Hartley Projects Ltd | Construction | 2022 |
| Harto Services Ltd | Information & communication | 2025 |
| Harton Search Ltd | Hospitality | 2020 |
| Hartride Limited | Health & social care | 2020 |
| Harts Lane Ardleigh Limited | Real estate | 2022 |
| Harvest Transportation LLP | | 2015 |
| Harvey & Company Electrical Services Ltd | Construction | 2010 |
| Haslar Developments Limited | Construction | 2009 |
| Haslien Studio Ltd | Arts & recreation | 2026 |
| Hasmonean Racing Ltd | Other services | 2022 |
| Hassingham Limited | Health & social care | 2005 |
| Hastingwood Developments (Foster Street) Ltd | Real estate | 2017 |
| Hastingwood Developments (Retirement) Ltd | Real estate | 2021 |
| Hastingwood Developments Limited | Real estate | 1992 |
| Hastingwood High Beech Limited | Real estate | 2017 |
| Hastingwood Holdings Limited | Administrative & support | 2017 |
| Hastingwood Investments (Retirement) Ltd | Real estate | 2021 |
| HAT Trick Creative Ltd | Arts & recreation | 2018 |
| Hatch Workspaces Ltd | Real estate | 2025 |
| Hatfield Grove (Hatfield Peverel) Management Company Limited | Real estate | 2020 |
| Hauslobby Limited | Real estate | 2026 |
| Haven Court RTM Company Ltd | Administrative & support | 2010 |
| Haven Street CIC | Hospitality | 2021 |
| Havilar Limited | Health & social care | 2019 |
| Hawk Building Services Ltd | Manufacturing | 2022 |
| Hayat Estates Limited | Manufacturing | 2012 |
| Hayath Food Limited | Hospitality | 2006 |
| Hayya Fitness Limited | Wholesale & retail | 2020 |
| Haze Parcels LLP | | 2015 |
| Hazel Real Estate Limited | Real estate | 2017 |
| Hazell Sets Ltd | Arts & recreation | 2025 |
| Hazelwood Dental Practice Limited | Health & social care | 2017 |
| Hazey Crane & Remote Head Services Limited | Information & communication | 2013 |
| HB London Property Investments Limited | Real estate | 2017 |
| HB Real Estate Ltd | Real estate | 2019 |
| Hbhy Ltd | Health & social care | 2019 |
| Hbjt Home Ltd | Real estate | 2023 |
| HD Investments 126 Ltd | Real estate | 2019 |
| HD Investments 18 Limited | Real estate | 2018 |
| HD Investments 180 Limited | Real estate | 2019 |
| HD Investments 36 Limited | Real estate | 2018 |
| Hdev Property Management Limited | Real estate | 2019 |
| HDF - Farm & Shop LLP | | 2016 |
| HDF Rentals Ltd | Hospitality | 2015 |
| HDG Dash Ltd | Real estate | 2022 |
| HDG Projects Limited | Manufacturing | 2014 |
| HDS Electric Contractors Limited | Construction | 2017 |
| He's There Ltd | Construction | 2021 |
| Head Shed App Ltd | Information & communication | 2022 |
| Healing Force Limited | Health & social care | 2013 |
| Health and Gardens Limited | Administrative & support | 2013 |