| HAC IT Ltd | Other services | 2018 |
| Haddenham Osteopathic Clinic Limited | Health & social care | 2009 |
| Haddon Court (1999) Limited | Households | 1999 |
| Hadeed Mart Limited | Wholesale & retail | 2024 |
| Hadid Sons Ltd | Financial services | 2022 |
| Hadleigh Court (Willesden) Residents Association Limited | Households | 1987 |
| Hadventurous Limited | Professional & scientific | 2025 |
| Hafiz Halal Meat & Groceries Limited | Wholesale & retail | 2020 |
| Haflim Ltd | Health & social care | 2026 |
| Hafren Advisory Limited | Professional & scientific | 2024 |
| Hafsa Catering Limited | Hospitality | 2015 |
| Hagden Services Limited | Administrative & support | 2016 |
| Haggle Hive Ltd | Information & communication | 2026 |
| Hagha Ltd | Real estate | 2026 |
| Hagley Road West Limited | Hospitality | 2022 |
| Haiderco Ltd | Wholesale & retail | 2025 |
| Hair by Mike Limited | Other services | 2023 |
| Haircare London Limited | Other services | 2021 |
| Hairdo Studio Ltd | Other services | 2023 |
| HAL 3 Developments London Ltd | Administrative & support | 2020 |
| HAL 3 Ltd | Administrative & support | 2019 |
| Halal Fresh Poultry and Meat Ltd | Wholesale & retail | 2025 |
| Halalification Ltd | Professional & scientific | 2025 |
| Halcyon (London) Limited | Professional & scientific | 2009 |
| Halcyon System Services Limited | Information & communication | 2015 |
| Haleena Firaaz Ltd | Wholesale & retail | 2026 |
| Halex Properties Limited | Real estate | 2006 |
| Half Moon Holdings Limited | Financial services | 2001 |
| Half Moon Management Company Limited | Households | 1985 |
| Hallidays (Antiques) Limited | Wholesale & retail | 1961 |
| Halliford Accountancy Services Ltd | Professional & scientific | 2017 |
| Hallmark Estate and Property Management Limited | Administrative & support | 2004 |
| Hallmark Property Management Limited | Real estate | 2002 |
| Hallsworth Press Ltd | Information & communication | 2014 |
| Halton Wood Estate Management Company Limited | Households | 2001 |
| Ham-Line Limited | Wholesale & retail | 2025 |
| Hamble Self-Storage Company Limited | Transport & logistics | 2009 |
| Hambleton Decorating Limited | Administrative & support | 1984 |
| Hamburg Doner Ltd | Hospitality | 2024 |
| Hamdan Enterprises Ltd | Wholesale & retail | 2019 |
| Hamed Laundry Limited | Other services | 2013 |
| Hamerville Events Limited | Extraterritorial | 2012 |
| Hamerville Media Group Limited | Information & communication | 1967 |
| Hamerville Online Media Limited | Extraterritorial | 2012 |
| Hamilton & Co Holdings Limited | Financial services | 2019 |
| Hamilton Wholesalers Limited | Wholesale & retail | 2025 |
| Hamilton's Primary Holding Limited | Financial services | 2020 |
| Hamlet Bespoke Builds Ltd | Construction | 2025 |
| Hammock Trading Ltd | Professional & scientific | 2016 |
| Hammond & Smith Ltd | Real estate | 2019 |
| Hammond Clarke Construction Limited | Administrative & support | 2019 |
| Hammond Clarke Group Limited | Professional & scientific | 2019 |
| Hammond Clarke Limited | Administrative & support | 2007 |
| Hampden Financial Partnerships Limited | Professional & scientific | 2015 |
| Hamsa (UK) Ltd | Transport & logistics | 2013 |
| Hamsard 3352 Limited | Administrative & support | 2014 |
| Hamsard 3353 Limited | Administrative & support | 2014 |
| Hamsi Investments Ltd | Financial services | 2023 |
| Handelt Marketing Limited | Information & communication | 2022 |
| Handlewell Academy Ltd | Education | 2022 |
| Handpost Farm Management Limited | Real estate | 2020 |
| Handyvan Ltd | Transport & logistics | 2023 |
| Hanem Consultancy Limited | Professional & scientific | 2020 |
| Hanem Properties Ltd | Real estate | 2017 |
| Hanley Group Holdings Ltd | Financial services | 2023 |
| Hanley Property Investments Ltd | Real estate | 2023 |
| Hanna Property Investments Ltd | Real estate | 2024 |
| Hanover Court Freehold Limited | Real estate | 2006 |
| Hanover Court Management Services Limited | Real estate | 2019 |
| Hanover Global Services Limited | Administrative & support | 2010 |
| Hanover Leadership Solutions Limited | Professional & scientific | 2025 |
| Hanover Search Group Ltd | Administrative & support | 2009 |
| Hanover Search Holdings Limited | Financial services | 2014 |
| Hanovers Care Limited | Health & social care | 2021 |
| Hansford Group Holdings Limited | Financial services | 2024 |
| Hansford Haircare LLP | | 2009 |
| Hansford Holdings Limited | Other services | 2000 |
| Hansford Impex LLP | | 2012 |
| Hansford Investments Limited | Real estate | 2017 |
| Hanstead House Management Company Limited | Households | 2020 |
| Hansuke Consulting Limited | Professional & scientific | 2016 |
| Hansuke Digital Limited | Information & communication | 2023 |
| Happiher Limited | Health & social care | 2023 |
| Happy & Walnut Studio Ltd | Manufacturing | 2024 |
| Happy Chapps Ltd | Professional & scientific | 2020 |
| Happy Flavours Caribbean Takeaway Ltd | Hospitality | 2023 |
| Happy GUY Ltd | Information & communication | 2022 |
| Happy Hairuk Ltd | Other services | 2022 |
| Happybeescleaning Ltd | Administrative & support | 2017 |
| Haque Trades Limited | Construction | 2016 |
| Harbourline UK Ltd | Wholesale & retail | 2025 |
| Harcap Services (UK) Ltd | Professional & scientific | 2014 |
| Hard MD Construction Ltd | Construction | 2025 |
| Hardcover Ltd | Information & communication | 2023 |
| Hardie Management Co Ltd | Households | 2022 |
| Harding Property Limited | Real estate | 2016 |
| Hardy Wellings Limited | Wholesale & retail | 2014 |
| Hare Krishna Movement United Kingdom | Other services | 2023 |
| Harebreaks Gospel Church | Other services | 2026 |
| Hargenant Global Management Ltd | Administrative & support | 2015 |