| HAB Law Ltd | Administrative & support | 2020 |
| Hadleigh Lodge Owners Limited | Households | 2000 |
| Hadstead Lodge Flats (Freehold) Limited | Households | 1991 |
| HAH Communications Ltd | Professional & scientific | 2020 |
| Hail Ready Limited | Administrative & support | 2017 |
| Hair by Haylands Ltd | Other services | 2020 |
| Hair Island Limited | Wholesale & retail | 2025 |
| HAJ Estates Management Limited | Real estate | 2022 |
| Hala Medical Holdings Limited | Administrative & support | 2024 |
| Halcyon Foxes Development Limited | Construction | 2024 |
| Halcyon Property South East Limited | Real estate | 2021 |
| Hale END Fish and Chips Limited | Hospitality | 2018 |
| Hallmark Surveyors Limited | Administrative & support | 2014 |
| Hallums Health Management Limited | Professional & scientific | 2026 |
| Hami Homes Ltd | Wholesale & retail | 2025 |
| Hamilton Property Ventures Limited | Real estate | 2021 |
| Hamilton's Cold Brew Ltd | Wholesale & retail | 2019 |
| Hamlet Court Properties Ltd | Construction | 2018 |
| Hamlet Court Residents Ltd | Households | 2026 |
| Hammam Tutoring Ltd | Education | 2026 |
| Hammerspur Limited | Real estate | 2020 |
| Hamodia Newspaper Limited | Information & communication | 2000 |
| Hampshire Training Centre Limited | Education | 2024 |
| Hampton Haven LLP | | 2026 |
| Hanbury Street Holdings Limited | Financial services | 2019 |
| Hance Ltd | Administrative & support | 2022 |
| Handley-Chase Limited | Other services | 1993 |
| Haneef Inc Limited | Professional & scientific | 2017 |
| Hannah and Ayla Limited | Hospitality | 2023 |
| Hannah House Limited | Real estate | 2020 |
| Hannes Consulting Limited | Administrative & support | 2013 |
| Hanover AI (Group) Limited | Administrative & support | 2023 |
| Hans Leitert Sports Consulting Limited | Professional & scientific | 2015 |
| HAO and RU Properties Ltd | Real estate | 2018 |
| Happy Smiles Health Care Limited | Other services | 2015 |
| Hard Ploughing Enterprises (UK) Ltd | Real estate | 2021 |
| Hardeep Singh Anaesthetic Services Limited | Real estate | 2010 |
| Harmon Bond Developments Ltd | Real estate | 2022 |
| Harmony Construction Ltd | Construction | 2020 |
| Harris & Yamah Solutions Ltd | Hospitality | 2018 |
| Harris at Home Ltd | Real estate | 2014 |
| Harris Brown London Limited | Wholesale & retail | 2007 |
| Harrisco Limited | Professional & scientific | 2025 |
| Harrowview Developments Limited | Real estate | 1989 |
| Harts Heating Ltd | Financial services | 2020 |
| Haryana Services Limited | Construction | 2019 |
| Hasco Limited | Real estate | 2003 |
| Hashtag Aesthetics London Ltd | Other services | 2020 |
| Hashtaghair London Ltd | Other services | 2014 |
| Hashtaghair London Petts Wood Ltd | Administrative & support | 2017 |
| Hasmita Homes Ltd | Real estate | 2024 |
| Hass Transport Services Limited | Transport & logistics | 2025 |
| Hassan a Holdings Ltd | Financial services | 2026 |
| HAT & CAP Works Management Company Limited | Households | 2024 |
| Hatton Garden Diamond Limited | Wholesale & retail | 2025 |
| Hatton International Limited | Administrative & support | 2008 |
| Haug Ltd | Other services | 2020 |
| Haven House Foundation | Health & social care | 1994 |
| Haven House Trading Limited | Wholesale & retail | 2011 |
| Havers Consultancy Ltd | Professional & scientific | 2020 |
| Hawk Systems Ltd | Other services | 2007 |
| Hawker Homes Limited | Real estate | 2010 |
| Hayes & Wade Electrical Services Limited | Construction | 2025 |
| Haylands Beauty Clinic Ltd | Other services | 2017 |
| Haymacs Limited | Other services | 2023 |
| Hayward Security Service Ltd | Professional & scientific | 2014 |
| Hazfix Environmental Limited | Construction | 2025 |
| Hbem Investments Ltd | Financial services | 2025 |
| Hbrw Limited | Health & social care | 2022 |
| HD Private Ltd | Real estate | 2023 |
| Hdma Limited | Extraterritorial | 2020 |
| Health & Safety Risk Services Limited | Other services | 2003 |
| Health BAE Limited | Health & social care | 2021 |
| Healthaly Limited | Wholesale & retail | 2014 |
| Hearology Limited | Wholesale & retail | 2014 |
| Heat TEC (London) Ltd | Construction | 2011 |
| Helios Psychology and Consulting Limited | Health & social care | 2014 |
| Hell TAP Entertainment Limited | Administrative & support | 2014 |
| Helloback Technologies Ltd | Information & communication | 2025 |
| Henderson & Royce Consultants Ltd | Other services | 2017 |
| Henlew Ltd | Administrative & support | 2024 |
| Henry's Bartenders Limited | Administrative & support | 2024 |
| Henvar Limited | Construction | 2018 |
| Heparevive Limited | Financial services | 2025 |
| Herald Build Limited | Construction | 2004 |
| Herald Training & Development Ltd. | Information & communication | 2000 |
| Herbal Flow Limited | Health & social care | 2019 |
| Heritage Aluminium London Ltd | Construction | 2024 |
| Hertons Brickwork Specialists Limited | Construction | 2019 |
| Herts & Essex Aero Club Limited | Other services | 1946 |
| Hesp Management Company Limited | Households | 2025 |
| Hetu Enterprises Limited | Wholesale & retail | 2026 |
| Hexa Padel Ltd | Wholesale & retail | 2021 |
| Hexagon Tuition Ltd | Education | 2024 |
| Hfabbas Properties Ltd | Real estate | 2025 |
| HFL 2014 Ltd | Real estate | 2014 |
| HFS London Limited | Hospitality | 2009 |
| HFT Solutions Ltd | Information & communication | 2021 |
| HGZ Limited | Wholesale & retail | 2021 |
| HH Pharma Ltd | Wholesale & retail | 2025 |