| Harcombe Hill Management Limited | Households | 2018 |
| Harcourt Gardens Estate (Bath) Limited | Real estate | 2009 |
| Harcourt Pre-School Ltd | Education | 2016 |
| Hard Acre Building Limited | Construction | 2007 |
| Hard Pressed for Time (Cheltenham) Limited | Other services | 2005 |
| Hard Work Pays Ltd | Information & communication | 2017 |
| Hardacre Investments Limited | Real estate | 2014 |
| Hardacre Ventures Limited | Real estate | 2005 |
| Hardigg UK Limited | Administrative & support | 1999 |
| Hardil Logistics Services Limited | Transport & logistics | 2012 |
| Harding Bros (Shipping Contractors) Limited | Real estate | 1955 |
| Harding Brothers Holdings Limited | Wholesale & retail | 2007 |
| Harding Brothers Retail Limited | Wholesale & retail | 2007 |
| Harding Retail IHC Ltd | Wholesale & retail | 2020 |
| Hardis Consultants Ltd | Information & communication | 2003 |
| Hardisty Jones Associates Limited | Professional & scientific | 2011 |
| Hardrock Developments Limited | Construction | 2015 |
| Hardwicke Enterprise Limited | Manufacturing | 2008 |
| Hardwood Flooring Supplies Limited | Construction | 2023 |
| Hardwood Homes Southern Limited | Construction | 2012 |
| Hardy Consultancy Services Ltd | Professional & scientific | 2022 |
| Hardy Family Property Limited | Real estate | 2017 |
| Hardy Financial Planning Limited | Financial services | 2018 |
| Hardy Geoscience Ltd | Extraterritorial | 2023 |
| Hardy Palms Ltd | Wholesale & retail | 2024 |
| Hare and Hounds Limited | Hospitality | 2010 |
| Hare Forest School CIC | Education | 2023 |
| Hare OR Tortoise Limited | Health & social care | 2019 |
| Hare Over the Moon Management Limited | Households | 2018 |
| Hare Press Services Ltd | Professional & scientific | 2021 |
| Hares Contracting Ltd | Agriculture & fishing | 2023 |
| Hares Park Limited | Real estate | 2019 |
| Harewood House Residents Management Company Ltd | Households | 1987 |
| Harford Place Management Company Limited | Households | 2019 |
| Hargreaves Lansdown (Nominees) Limited | Professional & scientific | 1984 |
| Hargreaves Lansdown Advisory Services Limited | Financial services | 1998 |
| Hargreaves Lansdown Asset Management Limited | Financial services | 1985 |
| Hargreaves Lansdown EBT Trustees Limited | Professional & scientific | 1997 |
| Hargreaves Lansdown Fund Managers Ltd. | Financial services | 1992 |
| Hargreaves Lansdown Group Limited | Administrative & support | 2024 |
| Hargreaves Lansdown Insurance Brokers Limited | Professional & scientific | 1984 |
| Hargreaves Lansdown Investment Management Limited | Professional & scientific | 2000 |
| Hargreaves Lansdown Limited | Financial services | 1987 |
| Hargreaves Lansdown Pensions Limited | Professional & scientific | 2000 |
| Hargreaves Lansdown Pensions Trustees Limited | Professional & scientific | 1983 |
| Hargreaves Lansdown Savings (Nominees) Limited | Professional & scientific | 2017 |
| Hargreaves Lansdown Savings Limited | Financial services | 2013 |
| Hargreaves Lansdown Stockbrokers Ltd | Professional & scientific | 1984 |
| Hargreaves Lansdown Trustee Company Limited | Professional & scientific | 2006 |
| Hargreaves Nexus EV Ltd | Wholesale & retail | 2024 |
| Hari House Catering Limited | Hospitality | 2025 |
| Hari Seddon Holdings Limited | Financial services | 2024 |
| Haringey Schools Services Limited | Real estate | 2000 |
| Harini Anaesthetics Private Limited | Health & social care | 2021 |
| Harken Consulting Ltd | Information & communication | 2004 |
| Harker Systems Consulting Ltd | Professional & scientific | 2026 |
| Harkiss Finance Limited | Financial services | 2014 |
| Harland Business Services Ltd | Administrative & support | 2012 |
| Harlender-Transport Ltd | Transport & logistics | 2014 |
| Harlequin Motor Co Bristol Ltd | Wholesale & retail | 2026 |
| Harley Court (Maintenance) Limited | Households | 1965 |
| Harley Hound Limited | Construction | 2014 |
| Harley House Care Home Limited | Health & social care | 2009 |
| Harley Orthopaedic Group Limited | Health & social care | 2025 |
| Harley Street Cardiology Ltd | Health & social care | 2024 |
| Harley Street Rooms Limited | Hospitality | 2025 |
| Harlow & Co Bristol Ltd | Other services | 2018 |
| Harlow (Broad Haven) Ltd | Hospitality | 2022 |
| Harlow Construction (Bristol & Bath) Limited | Construction | 2025 |
| Harlow Construction (Bristol) Ltd | Construction | 2019 |
| Harlyn Farmhouse Ltd | Real estate | 2024 |
| Harmnay Realty Ltd | Real estate | 2019 |
| Harmon Healthcare Ltd | Other services | 2025 |
| Harmonia in Cleaning Ltd | Administrative & support | 2023 |
| Harmoniq Energy Ltd | Wholesale & retail | 2025 |
| Harmoniq Technologies Ltd | Wholesale & retail | 2025 |
| Harmony Cleaning Service Ltd | Administrative & support | 2014 |
| Harmony Foods Ltd | Hospitality | 2019 |
| Harmony Home-Led Care Limited | Health & social care | 2020 |
| Harmony Homecare Support UK Limited | Health & social care | 2024 |
| Harmony Premium Home Limited | Administrative & support | 2026 |
| Harmovia Global Trade Ltd | Wholesale & retail | 2025 |
| Harold Hockey Limited | Real estate | 1956 |
| Harold Stephens Estate Planning Ltd | Administrative & support | 2021 |
| Harold Stephens Ltd | Financial services | 2011 |
| Harp. J Solutions Ltd | Real estate | 2021 |
| Harpa Properties Ltd | Real estate | 2023 |
| Harpen Project Management Limited | Professional & scientific | 2024 |
| Harper Gray Limited | Professional & scientific | 2015 |
| Harper James Developments Limited | Construction | 2016 |
| Harper Lark Limited | Financial services | 2021 |
| Harper Tovey Limited | Professional & scientific | 2026 |
| Harper Victoria Limited | Other services | 2018 |
| Harperino Osteopaths Limited | Health & social care | 2006 |
| Harpham Enterprises Limited | Construction | 2026 |
| Harpoon Sports Concepts Ltd | Professional & scientific | 2025 |
| Harptree Dental Surgery Ltd | Health & social care | 2017 |
| Harridore Property Ltd | Real estate | 2020 |
| Harriet Davis Administration Ltd | Administrative & support | 2021 |
| Harriet Lee-Merrion Limited | Administrative & support | 2021 |