| Hailstorm Ltd | Real estate | 2019 |
| Hairification UK Limited | Wholesale & retail | 2024 |
| HAK and MED Incorporated Ltd | Education | 2015 |
| Halcyon Court (Staines) Residents Association Limited | Households | 1965 |
| Halewood Health Limited | Wholesale & retail | 2015 |
| Halliford Studios Ltd | Real estate | 2023 |
| Hamilton Court RTM Company Limited | Households | 2022 |
| Hamilton Fletcher UK Ltd | Real estate | 2017 |
| Hammersley & Company Ltd | Extraterritorial | 2000 |
| Hampshire Haig Property Ltd | Real estate | 2017 |
| HAN Fang UK Limited | Administrative & support | 2019 |
| HAN UK Trading Group Limited | Financial services | 2019 |
| Hanko Limited | Transport & logistics | 2014 |
| Harmony Home Solutions Ltd | Real estate | 2022 |
| Harmony Within Counselling Services Limited | Health & social care | 2023 |
| Harpers Home Developments Ltd | Construction | 2022 |
| Hartley Old Road Ltd | Construction | 2020 |
| Haseeb Optical Ltd | Health & social care | 2024 |
| Hatton Cross Haulage Ltd | Transport & logistics | 2021 |
| Haute Homes Ltd | Real estate | 2024 |
| Hawk EYE Digital Ltd | Information & communication | 2024 |
| Hawthorne and Finch Limited | Construction | 2025 |
| Haymur Limited | Real estate | 2018 |
| Hazal&Daoud Limited | Wholesale & retail | 2026 |
| HB Spaces Ltd | Other services | 2024 |
| HBA Construction Ltd | Construction | 2017 |
| HC Motors London Ltd | Wholesale & retail | 2025 |
| Hclw Ltd | Professional & scientific | 2024 |
| Headache Academy Limited | Health & social care | 2018 |
| Headache Masterclass Ltd | Health & social care | 2009 |
| Headache Pro Limited | Health & social care | 2016 |
| Health and Public Care Ltd | Administrative & support | 2025 |
| Health Hub Community CIC | Health & social care | 2024 |
| Hear - on Ltd | Wholesale & retail | 2024 |
| Heart Beat Cardio Limited | Health & social care | 2024 |
| Heather Court (Avondale) Management Company Limited | Households | 1984 |
| Heathrow Building Supplies Ltd | Wholesale & retail | 2020 |
| Heathrow Corporate Chauffeurs Ltd. | Transport & logistics | 2016 |
| Heathrow Industrial Recycling Ltd | Wholesale & retail | 2018 |
| Heathrow Logistic Solution Ltd | Transport & logistics | 2022 |
| Heathrow London Properties Ltd | Real estate | 2024 |
| Heathrow Messenger Service Limited | Transport & logistics | 1967 |
| Heathrow Tyres and Specialist Ltd | Wholesale & retail | 2024 |
| Heathrow Vehicle Solutions Limited | Wholesale & retail | 2007 |
| Heating and Plumbing Systems Solutions Limited | Construction | 2010 |
| Heaven Autos Ltd | Wholesale & retail | 2025 |
| Heaven Holdings Limited | Real estate | 2016 |
| Heavens Aviation Limited | Transport & logistics | 2022 |
| Helen Grogan Tuition Limited | Education | 2014 |
| Heli-Tele Ltd | Information & communication | 2014 |
| Helpful Consultants Limited | Information & communication | 1991 |
| Heneways UK Limited | Transport & logistics | 2007 |
| Henrique Campos Ltd | Transport & logistics | 2019 |
| Herbal Real Limited | Wholesale & retail | 2014 |
| Herin Trading Co. Ltd. | Administrative & support | 2018 |
| Heritage Notary Public Limited | Professional & scientific | 2024 |
| Heritage Stone Steps Ltd | Construction | 2017 |
| Heritage World Press Limited | Information & communication | 2009 |
| Heron Farms Limited | Agriculture & fishing | 1965 |
| Herons Rest Developments Ltd | Real estate | 2018 |
| Herons Rest Properties Ltd | Hospitality | 2019 |
| Herons Rest Property Consultancy Ltd | Real estate | 2021 |
| Hero’S Punch Limited | Manufacturing | 2024 |
| Herts Singing School Ltd | Education | 2017 |
| Hesham Centrino Ltd | Information & communication | 2024 |
| HGB Enterprises Ltd | Wholesale & retail | 2023 |
| HGV Road Trans Limited | Transport & logistics | 2022 |
| HI Peak Feeds Limited | Agriculture & fishing | 1972 |
| HI Peak Organic Food Limited | Extraterritorial | 2022 |
| HI SMD Group Limited | Financial services | 2025 |
| Hibburt Holdings Ltd | Real estate | 2024 |
| Highgate Lane Management Co. Limited | Real estate | 1976 |
| Higoo Limited | Real estate | 2019 |
| Hill View Grab Solutions Ltd | Manufacturing | 2022 |
| Hill View Home Solutions Ltd | Real estate | 2025 |
| Hillingdon Care Village Ltd | Real estate | 2019 |
| HIR Ltd | Water & waste | 2013 |
| Hithermoor Farm Limited | Real estate | 2024 |
| HKU Ltd | Information & communication | 2026 |
| HM Elite Interiors Limited | Construction | 2025 |
| Holiday Nails Spa Ltd | Other services | 2026 |
| Hollar Gabriels UK Limited | Construction | 2015 |
| Holmwood Newco Limited | Agriculture & fishing | 2025 |
| Home & Nurture Ltd | Wholesale & retail | 2024 |
| Home Cleaning Rafal Dabrowski Ltd | Administrative & support | 2017 |
| Home Sweet Home Management Ltd | Real estate | 2023 |
| Homes of Heaven Ltd | Real estate | 2022 |
| Honeysuckle Residents Company Limited | Households | 2000 |
| Hope Alliance Limited | Other services | 2018 |
| Hopkins Plumbing & Heating Solutions Ltd | Construction | 2024 |
| Horizon Aerospace Limited | Professional & scientific | 2003 |
| Horizon Courier Limited | Transport & logistics | 2024 |
| Horton Plumbers Ltd | Construction | 2016 |
| Hot Dawgz Ltd | Hospitality | 2023 |
| Houghton Rookery Limited | Households | 2013 |
| House of Zaikha Limited | Hospitality | 2024 |
| House Special Limited | Hospitality | 2011 |
| Howard Barber Associates Limited | Professional & scientific | 1996 |
| Hpjss Limited | Transport & logistics | 2024 |
| HRJ Real Estate Limited | Real estate | 2023 |