| Hocroft Trust Limited | Extraterritorial | 1946 |
| Holidays by Vivian Ltd | Administrative & support | 2025 |
| Holistic Reach Consultancy Ltd | Public administration | 2023 |
| Holisticare Limited | Health & social care | 2006 |
| Holkham Construction Ltd | Construction | 2026 |
| Holland Interiors Limited | Professional & scientific | 2026 |
| Hollie Private Practice Limited | Administrative & support | 2025 |
| Hollrist Limited | Professional & scientific | 2021 |
| Holly Sims Design Ltd | Professional & scientific | 2023 |
| Holman & Co Recruitment Ltd | Administrative & support | 2026 |
| Holt Farm Lettings Ltd | Hospitality | 2019 |
| Holtronic Limited | Professional & scientific | 2021 |
| Home & DRY Sussex Limited | Administrative & support | 2012 |
| Home Hill Flowers Ltd | Wholesale & retail | 2021 |
| Homely Essentials Ltd | Wholesale & retail | 2025 |
| Homenest Interiors Ltd | Construction | 2022 |
| Homeworks GRP Ltd | Other services | 2013 |
| HOP Kingdom C.I.C. | Manufacturing | 2016 |
| Hopes and Dreams (London) Limited | Administrative & support | 2011 |
| Horozov Ltd | Wholesale & retail | 2020 |
| Hospitality 1 Limited | Administrative & support | 2025 |
| Hospitality Property Solutions Limited | Professional & scientific | 2007 |
| Hotel Rafayel Limited | Hospitality | 2009 |
| Hotpod Yoga Bishop's Stortford Limited | Arts & recreation | 2025 |
| Houghton Move Limited | Transport & logistics | 2021 |
| Hounsdown Property Ltd | Construction | 2025 |
| House of Chorky Limited | Professional & scientific | 2026 |
| House of Panier Limited | Wholesale & retail | 2024 |
| House of Prayer for ALL Nations CIC | Other services | 2024 |
| Housemartin Property Development Ltd | Real estate | 2012 |
| Howard Andrew Associates Limited | Information & communication | 2021 |
| Howard Sanderson Gardening Limited | Administrative & support | 2009 |
| Howe Capital Holdings Limited | Financial services | 2024 |
| Howe Green Moat Management Company Limited | Households | 1999 |
| HP Quality Accounts Ltd | Professional & scientific | 2014 |
| HPL Financial Services Ltd | Financial services | 2021 |
| Hps-Ih Limited | Financial services | 2021 |
| HR for ALL Ltd | Administrative & support | 2022 |
| HR Page Consultancy Ltd | Professional & scientific | 2021 |
| HRD Medical Ltd | Health & social care | 2021 |
| HRM Consultants Limited | Professional & scientific | 2017 |
| HS Ware Management Limited | Households | 2018 |
| HSF Associates Limited | Construction | 2025 |
| Htrend Capital Ltd | Financial services | 2026 |
| Hublok Limited | Wholesale & retail | 2020 |
| Hudro Limited | Wholesale & retail | 2018 |
| Hughes Tax Consultancy Ltd | Professional & scientific | 2025 |
| Human Copywriting Ltd | Professional & scientific | 2024 |
| Human Law Limited | Professional & scientific | 2026 |
| Humboldt UK Ltd | Health & social care | 2018 |
| Hungry Browser Limited | Information & communication | 2008 |
| Hunt Capital Ltd | Construction | 2024 |
| Hunt-Rec Ltd | Administrative & support | 2022 |
| Hunter Grace Consultancy Limited | Professional & scientific | 2015 |
| Hunters Court Residents Association Limited | Households | 1986 |
| Huntly Homes Ltd | Construction | 2023 |
| Hutchison Medical Services Limited | Health & social care | 2025 |
| Hvbrand Ltd | Professional & scientific | 2025 |
| Hy-Tek Solutions Limited | Extraterritorial | 2024 |
| Hyde Grove Ltd | Real estate | 2023 |
| Hylton Heights Scaffolding Ltd | Construction | 2021 |
| I AM SO FLY Limited | Wholesale & retail | 2009 |
| I J G Engineering Design Limited | Professional & scientific | 2018 |
| I Know This Girl Ltd | Wholesale & retail | 2023 |
| I Tech Accessories Ltd | Wholesale & retail | 2017 |
| I-Merge Services Limited | Information & communication | 2025 |
| Iberlink Ltd | Administrative & support | 2012 |
| Ibrahim Advisors Ltd | Professional & scientific | 2023 |
| IC Accounts Ltd | Professional & scientific | 2018 |
| Icarus Property Investments Ltd | Real estate | 2019 |
| Icarus Renewable Energy Ltd | Construction | 2011 |
| ICC Property Management Limited | Real estate | 2025 |
| Iceni Wear Ltd | Wholesale & retail | 2019 |
| Icon Recruitment Services Limited | Education | 2013 |
| Iconic Influencer Limited | Arts & recreation | 2020 |
| Ideal Ventilation Ltd | Construction | 2019 |
| Ieva Benz Ltd | Administrative & support | 2018 |
| Ifit Blinds & Shutters Ltd | Construction | 2020 |
| Ifoaa Services Limited | Professional & scientific | 2026 |
| Ignitionuk AI Limited | Information & communication | 2026 |
| Ikenga Innovations Limited | Information & communication | 2017 |
| Illuminated Beverages Limited | Wholesale & retail | 2015 |
| ILX Consultancy Ltd | Professional & scientific | 2026 |
| IMA Studio Design Ltd | Professional & scientific | 2021 |
| Image Fusion Creations Limited | Professional & scientific | 2025 |
| Imarcomedia Ltd | Administrative & support | 2012 |
| Imarenen Ltd | Arts & recreation | 2026 |
| IMD Recruitment Services Ltd | Administrative & support | 2025 |
| IMH Advisory LLP | | 2013 |
| IMH Services Limited | Professional & scientific | 2016 |
| Imperial Home Improvements EA Ltd | Construction | 2026 |
| Imperial Home Improvements UK EA Ltd | Administrative & support | 2026 |
| Imperium (Highlands) Limited | Construction | 2025 |
| Imperium (Rowlands Castle) Limited | Real estate | 2018 |
| Imperium Construction Limited | Construction | 2020 |
| Imperium Group (Holdings) Limited | Financial services | 2018 |
| Imperium Group Developments Limited | Construction | 2020 |
| Imperium Holiday Homes Limited | Hospitality | 2022 |
| Imperium Property Rentals Limited | Real estate | 2020 |
| Impulse Alpine Ltd | Administrative & support | 2019 |