| Hawkeye Solutions Limited | Administrative & support | 2011 |
| Hayat & Partners Ltd | Professional & scientific | 2025 |
| Hayes IT Consultancy Limited | Information & communication | 2008 |
| Hayley Moore Media Limited | Information & communication | 2017 |
| Haytech Ltd | Information & communication | 2020 |
| Hayward Design Limited | Professional & scientific | 2003 |
| HCM Solutions Ltd | Information & communication | 2024 |
| Head Partners Limited | Other services | 2001 |
| Headlight Communications Ltd | Professional & scientific | 2012 |
| Healix Health Services Limited | Health & social care | 2000 |
| Healix Insurance Services Limited | Financial services | 2005 |
| Healix International Group Limited | Professional & scientific | 2016 |
| Healix International Limited | Health & social care | 2000 |
| Healix International Risk Management Services Limited | Financial services | 2015 |
| Healix IT Limited | Information & communication | 2005 |
| Healix Limited | Administrative & support | 2000 |
| Healix Management Limited | Financial services | 2016 |
| Healix Medical Services Limited | Health & social care | 2014 |
| Health at Hand Limited | Health & social care | 2006 |
| Health Ignite Ltd | Administrative & support | 2020 |
| Hearing Services London Limited | Wholesale & retail | 2016 |
| Hearken Performance Ltd | Professional & scientific | 2023 |
| Heather Court Management Company (Esher) Limited | Households | 1994 |
| Heathside Capital Limited | Real estate | 2022 |
| Heathside Property Developments Ltd | Real estate | 2020 |
| HEC Estates Ltd | Real estate | 2021 |
| Helaya Ltd | Real estate | 2026 |
| Helen Hatton Limited | Professional & scientific | 2018 |
| Helix Doctors Ltd | Information & communication | 2026 |
| Hellenic Holdings Limited | Financial services | 2019 |
| Hemmy Ltd | Construction | 2012 |
| Henfold Lakes Limited | Extraterritorial | 2009 |
| Hereford Securities Limited | Professional & scientific | 1987 |
| Hermance Limited | Professional & scientific | 2016 |
| Hewmann Peaks Ltd | Financial services | 2011 |
| Hh-Re Ltd | Real estate | 2026 |
| HI Design Landscaping Limited | Administrative & support | 2016 |
| Hi-Point Sales Limited | Professional & scientific | 1989 |
| Hi-Pro Limited | Other services | 1991 |
| Hidden Close (Molesey) Management Company Limited | Real estate | 2010 |
| High Wire Brighton Limited | Real estate | 2017 |
| Highland Accounting Services Limited | Professional & scientific | 1997 |
| Highrise Digital Ltd | Information & communication | 2016 |
| Highview Properties Limited | Real estate | 1988 |
| Hillersdon Investments Ltd | Financial services | 2016 |
| Hillfield Court (Esher) (1993) Limited | Households | 1993 |
| Hillmont Associates Limited | Professional & scientific | 2019 |
| Hillock Family Limited | Manufacturing | 2025 |
| Hinchley Park Developments Limited | Construction | 2010 |
| Hinchley Wood Learning Partnership | Education | 2011 |
| Hinde Pharma Consulting Limited | Professional & scientific | 2013 |
| Hinks Harris Ltd | Professional & scientific | 2019 |
| Hiper Energy Limited | Manufacturing | 2022 |
| Hiper Pile Limited | Construction | 2022 |
| Hipper Partners LLP | | 2022 |
| Hippo Events Limited | Administrative & support | 2017 |
| Hitchin 2022 Ltd | Professional & scientific | 2022 |
| Hockering FS Limited | Professional & scientific | 2023 |
| HOK Property Services Ltd | Households | 2026 |
| Hollydale Developments Limited | Construction | 1991 |
| Holmes Street Property Limited | Real estate | 1987 |
| Home - Worx Handyman Ltd | Construction | 2024 |
| Home Insight Ltd | Professional & scientific | 2025 |
| Honourable Society of Knights of the Round Table | Health & social care | 1964 |
| Horgan a Priori Limited | Professional & scientific | 2016 |
| Hot Wire Extensions Ltd | Arts & recreation | 2017 |
| Houde Financial Services Limited | Professional & scientific | 2017 |
| HOW NOT What Limited | Professional & scientific | 2024 |
| Howard Nowell Life Planning Ltd | Professional & scientific | 2023 |
| Howitts Close Management Company Limited | Households | 1997 |
| HS Recruitment and Employment Ltd | Administrative & support | 2022 |
| Hsmu Ltd | Health & social care | 2021 |
| Huckleberry Associates Ltd | Professional & scientific | 2013 |
| Hudson Construction Ltd | Construction | 2011 |
| Hudson Health & Safety Ltd | Construction | 2013 |
| Human Connections Limited | Health & social care | 2017 |
| Hummings Bar & Cafe Limited | Other services | 2009 |
| Hunny Tees Limited | Wholesale & retail | 2015 |
| Huntington Advisory Limited | Professional & scientific | 2013 |
| Huxley Close Ltd | Real estate | 2019 |
| Hyperplanes Ltd | Information & communication | 2015 |
| I-Echo Ltd | Manufacturing | 2014 |
| IAA Global Ltd | Other services | 2026 |
| Iain Macdonald Design Limited | Administrative & support | 2008 |
| Icklin Ltd | Financial services | 2015 |
| Icontrolhub Limited | Manufacturing | 2013 |
| Idaho Jones Ltd | Wholesale & retail | 2015 |
| Idchem Consulting Limited | Professional & scientific | 2025 |
| Ideal-B Limited | Construction | 2024 |
| Identika Ltd | Professional & scientific | 2023 |
| IGB Architect Limited | Professional & scientific | 2012 |
| IHG Consulting Limited | Professional & scientific | 2025 |
| Ikonik Drafting Ltd. | Construction | 2013 |
| ILW Consulting Ltd | Professional & scientific | 2025 |
| Immersive Interior Ltd | Professional & scientific | 2024 |
| IN a Dune Jail Ltd | Real estate | 2018 |
| IN a Real Pickle Ltd | Manufacturing | 2024 |
| Inetum UK Limited | Information & communication | 2004 |
| Infinity Trustees Ltd | Professional & scientific | 2013 |
| Infinium Projects UK, Ltd | Administrative & support | 2026 |