| H-Sparks Ltd | Construction | 2024 |
| H-Z Healthcare Limited | Professional & scientific | 2021 |
| H. Hodgkins & SON Limited | | 1984 |
| H.A. Care Plus Limited | Health & social care | 2018 |
| H.Cube Traders Ltd | Wholesale & retail | 2023 |
| H.E.C. (Precision) Limited | Manufacturing | 1994 |
| H.K London Limited | Real estate | 2012 |
| H.S Dhami Ltd | Construction | 2017 |
| H.S. Heating & Plumbing Ltd | Construction | 2020 |
| H2B UK Ltd | Wholesale & retail | 2017 |
| Haad Logistics Limited | Transport & logistics | 2025 |
| Haad's Construction Limited | Construction | 2018 |
| Haare Limited | Wholesale & retail | 2020 |
| HAD Distributions Ltd | Wholesale & retail | 2024 |
| Hadiya Driving School Limited | Education | 2025 |
| Haenterprisess Ltd | Wholesale & retail | 2025 |
| Hafeez Jewellers Limited | Wholesale & retail | 2020 |
| Hafiz Enterprises Ltd | Professional & scientific | 2019 |
| HAG Masonry and Wire Ltd | Construction | 2026 |
| Haider Decor Ltd | Professional & scientific | 2024 |
| Hair & Beauty Clippers Ltd | Wholesale & retail | 2016 |
| Hair and Beauty(Feltham) Ltd | Other services | 2015 |
| Hair Crew of Watford Limited | Administrative & support | 2012 |
| Haitong Trading Ltd | Wholesale & retail | 2023 |
| Hajveries Ltd | Hospitality | 2024 |
| Halcyon Health Limited | Health & social care | 2022 |
| Haldiram Hospitality UK Limited | Hospitality | 2025 |
| Haldiram Overseas Limited | Manufacturing | 2002 |
| Hall Street Investments Limited | Real estate | 2022 |
| Halla Properties Ltd | Real estate | 2026 |
| Halla Tours Ltd | Administrative & support | 2025 |
| Hallmark Roofing and Guttering Ltd | Construction | 2024 |
| Hamdard Developments Limited | Households | 2026 |
| Hammervm Ltd | Information & communication | 2024 |
| Hamton Direct Ltd | Wholesale & retail | 2025 |
| Hamza Flavas (Southall) Ltd | Hospitality | 2023 |
| Hamza Flavas Ltd | Wholesale & retail | 2020 |
| Hamza PAN and Juice Limited | Hospitality | 2017 |
| HAN Bazaar Co. Ltd | Wholesale & retail | 2024 |
| Hana Zain Ltd | Wholesale & retail | 2025 |
| Handy Heaven Limited | Wholesale & retail | 2024 |
| Hani E Management Limited | Professional & scientific | 2015 |
| Hanny & Jazz Ltd | Wholesale & retail | 2021 |
| Hanworth Roofing Ltd | Construction | 2017 |
| Happive Ltd | Information & communication | 2025 |
| Happy BAL Constructions Limited | Construction | 2024 |
| Happy Miles Limited | Administrative & support | 2026 |
| Happyness Group Limited | Information & communication | 2026 |
| Happyness Homes Limited | Real estate | 2026 |
| Haqq Enterprises Limited | Wholesale & retail | 2019 |
| HAR Bassi Consulting Limited | Administrative & support | 2014 |
| Hare Krishna Travels Ltd | Transport & logistics | 2021 |
| Hari OM Construction Ltd | Construction | 2017 |
| Hari OM Fruit and VEG Ltd | Administrative & support | 2025 |
| Hari OM Properties & Rental Limited | Real estate | 2025 |
| Harikaran Supermarket Limited | Wholesale & retail | 2022 |
| Harji Construction Ltd | Construction | 2026 |
| Harjit Concrete Limited | Construction | 2020 |
| Harjot Film Productions Ltd | Information & communication | 2024 |
| Harjot Kumar Ltd | Construction | 2021 |
| Harleen Construction Limited | Construction | 2023 |
| Harley Street Dental Art Clinic Ltd | Health & social care | 2022 |
| Harman Construction United Ltd | Construction | 2017 |
| Harmondsworth Proprietors Limited | Real estate | 2025 |
| Harneet Ltd | Wholesale & retail | 2023 |
| Harnek Singh Enterise Ltd Ltd | Wholesale & retail | 2025 |
| Harold Property Limited | Real estate | 2019 |
| Haroon Collection Ltd | Wholesale & retail | 2023 |
| Harpal Couriers Limited | Transport & logistics | 2026 |
| Harpy Construction Services Ltd | Construction | 2024 |
| Harraj Investments Ltd | Real estate | 2025 |
| Harrow Legal Centre Limited | Professional & scientific | 2025 |
| Harry Fashion Jewellery Ltd | Other services | 2016 |
| Harry Garry Construction Ltd | Construction | 2024 |
| Harry UK Services Ltd | Wholesale & retail | 2025 |
| Harry Vishal Limited | Construction | 2025 |
| Hars.Shaind Ltd | Wholesale & retail | 2025 |
| Harsh Mart Ltd | Wholesale & retail | 2026 |
| Harshie Consultancy Ltd | Professional & scientific | 2018 |
| Harshleen Ltd | Administrative & support | 2025 |
| Harshpreet Properties Limited | Real estate | 2026 |
| Harsimrans Fashion Ltd | Wholesale & retail | 2025 |
| Harveen Ltd | Wholesale & retail | 2019 |
| Harvinder Design and Construct Ltd | Construction | 2023 |
| Harwin (UK) Limited | Wholesale & retail | 2007 |
| Haryanvi Sweet & Spicey Ltd | Hospitality | 2026 |
| Hasdaf Business Developer Ltd | Information & communication | 2013 |
| Hash Collection Limited | Wholesale & retail | 2001 |
| Hashmats Care Limited | Professional & scientific | 2010 |
| Hashmats Health Ltd | Manufacturing | 2010 |
| Hashmats Limited | Other services | 2010 |
| Hashmats Management Ltd | Administrative & support | 2026 |
| Hashmats Pharma Ltd | Wholesale & retail | 2010 |
| Hashmats Property Ltd | Real estate | 2026 |
| Havelock Family Centre | Health & social care | 2006 |
| Haven Bites Ltd | Hospitality | 2025 |
| Hayes Stocks PVT Ltd | Wholesale & retail | 2025 |
| Haykal Driving School Limited | Education | 2026 |
| Hayre Investments & Developments Limited | Real estate | 2004 |
| Hayward Bodyworks Limited | Manufacturing | 2025 |