| Higgs&Hughes Ltd | Professional & scientific | 2015 |
| High Grade Fire and Security Technology Limited | Administrative & support | 2014 |
| High Mead (Harrow) Management Company Limited | Real estate | 2006 |
| High NET Worth Limited | Real estate | 2019 |
| High Peak Marketing Ltd | Wholesale & retail | 2026 |
| High Point Yeading Management Limited | Households | 2005 |
| High Profile Travel Ltd | Transport & logistics | 2025 |
| High Quality Fruits & Vegetables Limited | Wholesale & retail | 2010 |
| High Quality Trade Ltd | Wholesale & retail | 2021 |
| High Road Felixstowe Limited | Real estate | 2021 |
| High Speed Hire Ltd | Professional & scientific | 2020 |
| High Street Investment Property Limited | Real estate | 2016 |
| High Thoughts Ltd | Information & communication | 2008 |
| High View Investments Hounslow Ltd | Real estate | 2020 |
| High Voltage Wizards Ltd | Professional & scientific | 2022 |
| High West Homes Limited | Real estate | 2021 |
| Higham.Ai Limited | Information & communication | 2025 |
| Highbury Home Limited | Health & social care | 2024 |
| Highbury News Limited | Information & communication | 2013 |
| Higherhealth Ltd | Wholesale & retail | 2023 |
| Highfield Property Company(Northwood) Limited | Real estate | 1963 |
| Highgate Land and Development Agency Ltd | Professional & scientific | 2022 |
| Highgrove Hospitality Limited | Hospitality | 2025 |
| Highland and Hewn Limited | Hospitality | 2026 |
| Highland Comfort Limited | Transport & logistics | 2012 |
| Highlands Construction Management Limited | Construction | 2024 |
| Highmead Management Company Limited | Real estate | 2015 |
| Highq Global Solutions Limited | Information & communication | 2013 |
| Highstead Consulting Limited | Professional & scientific | 2010 |
| Highstead Partnership LLP | | 2019 |
| Hightail K9S Limited | Administrative & support | 2023 |
| Hightech Group (UK) Limited | Professional & scientific | 2000 |
| Hightech Motor Centre Limited | Administrative & support | 1995 |
| Highverge Limited | Construction | 2012 |
| Highview (2011) Ltd | Wholesale & retail | 1984 |
| Highway Trucking Ltd | Transport & logistics | 2020 |
| Highways Maintenance Ltd | Construction | 2021 |
| Higina Homes Ltd | Hospitality | 2024 |
| HII Speed Ltd | Wholesale & retail | 2019 |
| Hika&Co Ltd | Professional & scientific | 2026 |
| Hilda Holdings 2 Limited | Financial services | 2018 |
| Hilda Holdings Limited | Real estate | 2017 |
| Hiljon Investments Limited | Real estate | 1963 |
| Hill & Ellis Ltd. | Manufacturing | 2013 |
| Hill 112 1944 Ltd | Financial services | 2018 |
| Hill Go Limited | Real estate | 2023 |
| Hill Space Limited | Arts & recreation | 2021 |
| Hill's Finest Limited | Real estate | 2017 |
| Hillcrest Court Management Limited | Households | 1967 |
| Hillectrics Limited | Construction | 2014 |
| Hillier Business Consultancy Limited | Administrative & support | 2004 |
| Hillingdon Gateway Ltd | Construction | 2025 |
| Hillmans Global Ltd | Other services | 2025 |
| Hillmont Management Limited | Real estate | 2025 |
| Hillpride Limited | Wholesale & retail | 2000 |
| Hillrose Transport Limited | Transport & logistics | 2006 |
| Hills and Cows Limited | Hospitality | 2017 |
| Hillside Close (Banstead) Management Limited | Households | 1981 |
| Hillspoint Limited | Administrative & support | 1974 |
| Hillstar Finance Limited | Financial services | 2015 |
| Hillstar Investments (Old Town Hall) Limited | Real estate | 2017 |
| Hillstar Investments Limited | Real estate | 2015 |
| Hilltop House Limited | Health & social care | 2015 |
| Hillvenor Limited | Wholesale & retail | 2009 |
| Hiltan Investments Ltd | Financial services | 2022 |
| Hilton Textiles Limited | Wholesale & retail | 2011 |
| Hiltons Sales Ltd | Real estate | 2014 |
| Hilverdon Heritage Ltd | Real estate | 2019 |
| Hilverdon Investments Ltd | Financial services | 2018 |
| Hilverdon Limited | Construction | 2016 |
| Hilverdon Properties Ltd | Hospitality | 2019 |
| Himaara Investments Ltd | Hospitality | 2024 |
| Himaara Ltd | Professional & scientific | 2018 |
| Himalayan Salt Essence Ltd | Wholesale & retail | 2024 |
| Himalayas Consulting Services Ltd | Information & communication | 2025 |
| Himanshu Ltd | Administrative & support | 2025 |
| Himelight Holdings Limited | Financial services | 2018 |
| Himelight Limited | Real estate | 1999 |
| Himgiri Process Solutions Limited | Professional & scientific | 2007 |
| Himitsu LAB Limited | Information & communication | 2019 |
| Himmkg Ltd | Professional & scientific | 2024 |
| Hinchley Charitable Trust | Administrative & support | 2005 |
| Hindai Care Ltd | Public administration | 2022 |
| Hindes Property Ltd | Construction | 2025 |
| Hindmarsh Business Finance Ltd | Administrative & support | 2022 |
| Hindmarsh Property Investments Ltd | Real estate | 2024 |
| Hindsculture Limited | Manufacturing | 2013 |
| Hindus United CIC | Health & social care | 2026 |
| Hingston Rise Amenities Ltd | Households | 2019 |
| Hinton Residential Limited | Real estate | 2008 |
| HIP Event Management Ltd | Information & communication | 2020 |
| HIP PAC Ltd | Manufacturing | 2021 |
| Hippo Lite Services Limited | Arts & recreation | 2022 |
| Hippo Packaging Ltd | Manufacturing | 2024 |
| Hira Construction D&B Ltd | Construction | 2009 |
| Hira Developments Ltd | Construction | 2012 |
| Hira Properties Ltd | Construction | 2012 |
| Hiral Ventures Ltd | Hospitality | 2022 |
| Hirani Electrical Ltd | Construction | 2024 |
| Hirani Estates Ltd | Real estate | 2010 |