| H&O Exterior Cleaning Ltd | Administrative & support | 2025 |
| H&O Renovations and Property Services Ltd | Construction | 2025 |
| H-A Advisory Limited | Professional & scientific | 2021 |
| H0TB0X Sauna Ltd | Other services | 2025 |
| H2 Evolution Ltd | Energy | 2021 |
| H2H Construction Limited | Construction | 2018 |
| H3 Media Ltd | Information & communication | 2025 |
| Hacaruma Limited | Real estate | 2024 |
| Hacked OFF Grab Hire Ltd | Water & waste | 2018 |
| Hadis Beauty Bar Ltd | Other services | 2023 |
| Hado Inclusion CIC | Arts & recreation | 2025 |
| Hadraft Limited | Real estate | 2016 |
| Hadrel Enterprises Ltd | Wholesale & retail | 2025 |
| Hadrel Ltd | Wholesale & retail | 2025 |
| Haider & SON Limited | Construction | 2023 |
| Haines Security Limited | Administrative & support | 2006 |
| Hair & NOW Ltd | Other services | 2024 |
| Hair Actually Limited | Other services | 2016 |
| Hair Studio 92 Ltd | Other services | 2024 |
| Hairforce by Zahi Ltd | Other services | 2023 |
| Hakeem Said Limited | Wholesale & retail | 2025 |
| Hala Management Limited | Real estate | 2000 |
| Halal Foods Bargins Ltd | Wholesale & retail | 2026 |
| Halal Meatery Limited | Wholesale & retail | 2026 |
| Hallo Sailor! Limited | Professional & scientific | 2016 |
| Halloran Creative Ltd | Professional & scientific | 2025 |
| Hallyburton Ltd | Real estate | 2024 |
| Hallyburton ROW Management Company Limited | Households | 2007 |
| Halo Halo Internet Ltd | Wholesale & retail | 2016 |
| HAM Property Ltd | Construction | 2022 |
| Hamilton & Hamilton Management Holdings Limited | Real estate | 2010 |
| Hamilton & Hamilton Finance Limited | Real estate | 2010 |
| Hamilton & Hamilton Trustees Limited | Financial services | 2010 |
| Hamilton Finance (UK) Limited | Real estate | 2010 |
| Hamilton Hotels (UK) Limited | Hospitality | 2010 |
| Hamilton Leisure (UK) Limited | Hospitality | 2010 |
| Hamilton Palace Limited | Professional & scientific | 1992 |
| Hamilton Property Holdings Limited | Real estate | 1991 |
| Hamiltone Limited | Information & communication | 1994 |
| Hamiltons of Canterbury Limited | Manufacturing | 2017 |
| Hamiruma Limited | Real estate | 2024 |
| Hammersmith & Klein Limited | Real estate | 2006 |
| Hammonds Kitchens Limited | Professional & scientific | 2000 |
| Hampson Architects Ltd | Professional & scientific | 2023 |
| Hampton Terrace Property Management Company Limited | Households | 1990 |
| Handsome Devil Studios Ltd | Information & communication | 2025 |
| Hanga Soundlab Ltd | Information & communication | 2015 |
| Hangledale Limited | Households | 2000 |
| Hangleton Chaudhari Burger Limited | Hospitality | 2024 |
| Hangleton Community Association | Administrative & support | 2013 |
| Hangleton Dental Practice Limited | Health & social care | 2007 |
| Hanna Montela Mill Limited | Professional & scientific | 2025 |
| Hannah Adams Ltd | Professional & scientific | 2025 |
| Hannah Akinluyi Architecture and Interiors Limited | Professional & scientific | 2014 |
| Hannah House Freehold Limited | Households | 2004 |
| Hannah West Therapies Ltd | Other services | 2022 |
| Hannk Ltd | Information & communication | 2020 |
| Hanoi Tower Ltd | Information & communication | 2018 |
| Hanover Contracts Ltd | Administrative & support | 2016 |
| Hanover Payroll Solutions Limited | Administrative & support | 2025 |
| Happmount Limited | Real estate | 1965 |
| Happy Break Holidays Ltd | Extraterritorial | 2015 |
| Happy Mondays Limited | Wholesale & retail | 2020 |
| Happymatchbox Ltd | Wholesale & retail | 2026 |
| Harchester Research (International) Ltd | Administrative & support | 2024 |
| Harchester Research (UK) Ltd | Administrative & support | 2024 |
| Harder Than the Rock Ltd | Information & communication | 2020 |
| Harding Consulting Limited | Professional & scientific | 2007 |
| Hardings Print Solutions Limited | Administrative & support | 2009 |
| Harefield Sports Ltd | Manufacturing | 2021 |
| Hargovia Ltd | Information & communication | 2026 |
| Hark at HER Productions Ltd | Arts & recreation | 2026 |
| Harley Court Limited | Households | 1992 |
| Harleyford Limited | Households | 1993 |
| Harmonise Training Limited | Education | 2018 |
| Harmony 95 Consulting Ltd | Construction | 2025 |
| Harmony 95 Development Ltd | Construction | 2014 |
| Harmony 95 Home Improvement Ltd | Construction | 2021 |
| Harmony 95 Management Ltd | Construction | 2024 |
| Harp & Bright Limited | Professional & scientific | 2019 |
| Harriet's of Hove Ltd | Wholesale & retail | 2018 |
| Harrin Properties Limited | Households | 1989 |
| Harrington Technology Limited | Information & communication | 2019 |
| Harris Hassocks Ltd | Construction | 2016 |
| Harris Paley Schone Limited | Professional & scientific | 2004 |
| Harris-Nightingale Consultancy Limited | Information & communication | 2014 |
| Harrison Human Resources Limited | Administrative & support | 2023 |
| Harrisons of Hove Ltd | Hospitality | 2018 |
| Harrod Edits Limited | Information & communication | 2008 |
| Harrold Financial Planning Holdings Limited | Extraterritorial | 2007 |
| Harrold Financial Planning Limited | Financial services | 2007 |
| Hart Legal Limited | Administrative & support | 2025 |
| Harterson Limited | Construction | 2020 |
| Hartington Villas Limited | Households | 2015 |
| Hartley ASH Limited | Professional & scientific | 2026 |
| Hartley Bennett Ltd | Real estate | 2017 |
| Hartley Quinn Wilson Limited | Construction | 2000 |
| Hartville 24 Limited | Households | 2022 |
| Harukiya Coffee House Ltd | Wholesale & retail | 2022 |
| Hasco Kitchens Limited | Professional & scientific | 2025 |