| Hillside Ventures Limited | Wholesale & retail | 2017 |
| Hirani Diamonds Ltd. | Wholesale & retail | 2014 |
| Hirst PPM Associates Ltd | Professional & scientific | 2013 |
| Hitlab Limited | Information & communication | 2008 |
| Hkcp Ltd | Wholesale & retail | 2026 |
| HM Charles III Ltd | Extraterritorial | 2011 |
| HMR Media Limited | Construction | 2014 |
| Hobden Commercial Property Limited | Real estate | 2024 |
| HOC Limited | Real estate | 2012 |
| Hoho Studio Ltd | Professional & scientific | 2022 |
| Holbulk Limited | Wholesale & retail | 2025 |
| Holbulk Trading Ltd | Wholesale & retail | 2025 |
| Holder Properties Limited | Professional & scientific | 1938 |
| Holdken Limited | Administrative & support | 2020 |
| Home & Quarters Investments Limited | Administrative & support | 2021 |
| Home Ties Limited | Information & communication | 2018 |
| Homecare Support Ltd | Health & social care | 2017 |
| Homeless to Wellness Ltd | Information & communication | 2019 |
| Honest Wellness Ltd | Manufacturing | 2025 |
| Hopewell Property Ltd | Real estate | 2022 |
| Horizon Classics Ltd | Transport & logistics | 2019 |
| Hospital Switch Ltd | Information & communication | 2023 |
| Hospitality Crew Limited | Professional & scientific | 2019 |
| Hotels in India Limited | Administrative & support | 2022 |
| House Clearance London Ltd | Water & waste | 2024 |
| House of Gharats Denartistry Ltd | Health & social care | 2020 |
| House of Gharats Holdings Ltd | Financial services | 2025 |
| House of Gharats Properties Ltd | Real estate | 2024 |
| House of Libertine Ltd | Manufacturing | 2017 |
| HOUSES4GOOD Limited | Real estate | 2022 |
| Houzan Coaching LLP | | 2025 |
| Howard Richards Legal Services Limited | Real estate | 2020 |
| Howson Care Centre Limited | Health & social care | 1996 |
| HR Maximum Talent Ltd | Education | 2025 |
| HS Tuli Builders Ltd | Construction | 2024 |
| HSD Automotive Limited | Wholesale & retail | 2025 |
| HSP Hotels Ltd | Hospitality | 2017 |
| HT SSC Ltd | Education | 2025 |
| Hucclecote Retirement Holdings Limited | Real estate | 2016 |
| Hudson Nutley Limited | Administrative & support | 2016 |
| Huge Potential Ltd | Professional & scientific | 2024 |
| Humphrey Construction Limited | Construction | 2011 |
| Humphrey Foot & Ankle Limited | Health & social care | 2018 |
| Hungry LEO Restaurant Ltd | Hospitality | 2026 |
| Hunton Park Hospitality Limited | Hospitality | 2022 |
| Hunton Park Hotel Limited | Hospitality | 2021 |
| Huzaifa Smiles Ltd | Health & social care | 2025 |
| Hyde SSB (1) Limited | Real estate | 2022 |
| Hyper Projects Limited | Construction | 2022 |
| Hyperstatic Limited | Construction | 2022 |
| I G Healthcare Limited | Health & social care | 2013 |
| I-Tech Solutions & Consulting UK Limited | Information & communication | 2010 |
| IAN Gibson Services (London) Limited | Financial services | 2014 |
| IAN Hale Planning & Design Limited | Professional & scientific | 2012 |
| IAV Property Services Ltd | Real estate | 2023 |
| Ibotu Limited | Health & social care | 2022 |
| Iced T Ice Cream Parlour Limited | Manufacturing | 2026 |
| ICP Education Limited | Education | 2021 |
| Iebs Ltd | Information & communication | 2024 |
| Iesg Limited | Health & social care | 2014 |
| IF Systems Limited | Wholesale & retail | 2015 |
| Ifsport Leisure Ltd | Education | 2008 |
| Ignition Dance Productions Limited | Arts & recreation | 2024 |
| IHT Consulting Limited | Administrative & support | 2011 |
| IKA Epos Ltd | Professional & scientific | 2011 |
| Imella Store Limited | Wholesale & retail | 2025 |
| Imex Trading (UK) Limited | Wholesale & retail | 2000 |
| Immerse Educational Services Ltd | Education | 2021 |
| Immerse Summer Schools Limited | Education | 2020 |
| Impact Consultancy Ltd | Information & communication | 2011 |
| Impact Motion Ltd | Information & communication | 2016 |
| Impactron Global Limited | Information & communication | 2024 |
| Imparts Workshops Ltd | Education | 2026 |
| Imperial Quant Ltd | Professional & scientific | 2016 |
| Impexar Ltd | Wholesale & retail | 2010 |
| Implanttrack Ltd | Information & communication | 2026 |
| Inaxis Limited | Information & communication | 2008 |
| Independent Film Festivals Limited | Administrative & support | 2025 |
| Independent Mortgage Partnership Ltd | Financial services | 1999 |
| Indo-British Cultural Exchange Limited | Arts & recreation | 1999 |
| Indo-British Cultural Heritage Limited | Information & communication | 2025 |
| Infaserv Limited | Information & communication | 2004 |
| Infinite Referrals Limited | Professional & scientific | 2023 |
| Infinity Property Investments Ltd | Real estate | 2013 |
| Inflair Software Limited | Information & communication | 1994 |
| Influncr Ltd | Professional & scientific | 2021 |
| Informatics Consulting Ltd | Information & communication | 2013 |
| Informatics Consulting Services Ltd | Information & communication | 2025 |
| Inkerman Homes Limited | Real estate | 2022 |
| Inkot Limited | Wholesale & retail | 2004 |
| Inkwell Ltd | Professional & scientific | 2022 |
| Innovate Education Ltd | Education | 2024 |
| Innovative Analytics Ltd | Information & communication | 2021 |
| Innovative Facilities Management Limited | Real estate | 2017 |
| Innovative Property Holdings Limited | Real estate | 2019 |
| Innpride Limited | Real estate | 2013 |
| Inscope Projects Ltd | Administrative & support | 2016 |
| Insight Real Action Ltd | Professional & scientific | 2018 |
| Inso PAN Limited | Hospitality | 2023 |
| Inspira UK Limited | Professional & scientific | 2003 |