| Happy Creations Limited | Financial services | 2024 |
| Happy Garden Limited | Real estate | 1993 |
| Happy Headwork Community C.I.C. | Professional & scientific | 2021 |
| Happy Headwork Ltd | Education | 2025 |
| Happy Hounds (Wales) Ltd | Wholesale & retail | 2013 |
| Happy House Cleaners Ltd | Administrative & support | 2025 |
| Happy Stoat Limited | Wholesale & retail | 2024 |
| Happy Valley Consulting Limited | Professional & scientific | 2019 |
| Hapus Holidays Limited | Extraterritorial | 2017 |
| Hapus Management Limited | Extraterritorial | 2017 |
| Haque Solar Integrations Ltd | Energy | 2025 |
| Harbourline Supported Living Ltd Ltd | Hospitality | 2025 |
| Harcam Aesthetics Clinics Ltd | Other services | 2020 |
| Harcam Aesthetics Ltd | Other services | 2020 |
| Harcourt Litho Limited | Manufacturing | 1992 |
| Hard Knock Uptown Ltd | Other services | 2023 |
| Hard-Knock Limited | Other services | 2020 |
| Harding Helping Hands Ltd | Health & social care | 2025 |
| Harding Property Holdings Ltd | Real estate | 2021 |
| Harding Property Partnership LLP | | 2021 |
| Hardings Energy Services Ltd | Construction | 2019 |
| Hardy Evans Limited | Professional & scientific | 2010 |
| Harebell Investments Limited | Real estate | 2018 |
| Hargan Group Limited | Construction | 2019 |
| Hari OM Convenience Limited | Wholesale & retail | 2023 |
| Harley Street Mens Clinic Ltd | Extraterritorial | 2023 |
| Harley's Homes 2025 Ltd | Real estate | 2025 |
| Harmen Ltd | Wholesale & retail | 2026 |
| Harmony Wndows Limited | Construction | 2020 |
| Harper&Eloise Limited | Hospitality | 2025 |
| Harpers (Canterbury) Limited | Administrative & support | 2003 |
| Harries & Lynch Holdings Limited | Financial services | 2023 |
| Harrington Rees Limited | Real estate | 2025 |
| Harris and SON Joinery Limited | Manufacturing | 2018 |
| Harris Bros.(Pontypool)Limited | Construction | 1968 |
| Harris Kent Holdings Limited | Professional & scientific | 2025 |
| Harris Signs & Graphics Limited | Administrative & support | 2002 |
| Harrison Stationers (Swansea) Limited | Wholesale & retail | 2002 |
| Harry Bear Limited | Extraterritorial | 2021 |
| Harry Harries Holdings Limited | Financial services | 2023 |
| Harry's Heating & Plumbing Ltd | Construction | 2023 |
| Harry's Swansea CIC | Arts & recreation | 2025 |
| Harry's Taproom Limited | Hospitality | 2024 |
| Hartland Builders Limited | Construction | 2015 |
| Hartland Property Development Ltd | Construction | 2006 |
| Hartland SPV Limited | Real estate | 2025 |
| Hartley Roofing Ltd | Construction | 2019 |
| Hartley's Budget Cars Ltd | Wholesale & retail | 2026 |
| Hartshorn Clarke and Associates Limited | Health & social care | 2007 |
| Hartson Fire Limited | Manufacturing | 2016 |
| Hartz Electrix Ltd | Manufacturing | 2023 |
| Hartz Properties Limited | Real estate | 2023 |
| Harvey Clan Limited | Real estate | 2020 |
| Harwood Leon Ltd | Information & communication | 2013 |
| Hasmore Homes Limited | Construction | 2003 |
| Hasr Ltd | Transport & logistics | 2025 |
| Hassan Moallem Ltd | Construction | 2024 |
| Hassett Property Limited | Real estate | 2018 |
| Hasslefree Hampers Limited | Wholesale & retail | 2021 |
| Haswell Medical Services Ltd | Health & social care | 2025 |
| Hatherleigh Drive Limited | Real estate | 2024 |
| Haughton Sports Consultancy Limited | Arts & recreation | 2018 |
| Haul London Ltd | Wholesale & retail | 2021 |
| Haus Classics Ltd | Wholesale & retail | 2025 |
| Haus of Branding Limited | Professional & scientific | 2021 |
| Haus of Heathen Ltd | Wholesale & retail | 2023 |
| Haus of INK Ltd | Health & social care | 2026 |
| Havard M&E Solutions Ltd | Administrative & support | 2022 |
| Have YOU Seen This Ltd | Other services | 2019 |
| Haven Home Builders Limited | Construction | 2024 |
| Haven Home Investments Ltd | Real estate | 2017 |
| Haven Mortgages Ltd | Financial services | 2025 |
| Havenwood Care Homes Limited | Financial services | 2023 |
| Havilah House Limited | Manufacturing | 2024 |
| Havin Turkish Pastry Ltd | Manufacturing | 2020 |
| Hawkeye Surveys Limited | Professional & scientific | 2025 |
| Hawkfield Investment Limited | Wholesale & retail | 1999 |
| Hawkinsco Ltd | Real estate | 2024 |
| Hawthorn Villas Residents Association Limited | Households | 1995 |
| Hayaa GEM and Jewellers Ltd | Wholesale & retail | 2022 |
| Hayesandbeale Ltd | Hospitality | 2018 |
| Hayles Ventures Ltd | Wholesale & retail | 2026 |
| Hayley Delaney Consulting Limited | Information & communication | 2025 |
| Haystack Cafe Ltd | Hospitality | 2018 |
| Haystack Group Limited | Hospitality | 2024 |
| Hayward Couriers Limited | Transport & logistics | 2023 |
| Hayward Professional Services Limited | Professional & scientific | 2024 |
| Hazard Risk Control Training International Limited | Education | 2016 |
| Hazel House Limited | Professional & scientific | 2021 |
| Hazelvale Limited | Real estate | 2019 |
| Hazflo Ltd | Professional & scientific | 2025 |
| HB Associates VPP Limited | Arts & recreation | 2006 |
| HB Investments Limited | Real estate | 2001 |
| HCA Developments Ltd | Construction | 2024 |
| Hcdent Limited | Health & social care | 2023 |
| Hchr Trading AS Personology Ltd | Professional & scientific | 2002 |
| Hcjmed Limited | Health & social care | 2013 |
| Hclsa Ltd | Households | 2021 |
| HD Properties (SW) Ltd | Real estate | 2024 |
| HDG Surveys Limited | Professional & scientific | 2026 |