| Holm Security UK Limited | Extraterritorial | 2022 |
| Holson Property Ltd | Real estate | 2020 |
| Holt Property Limited | Real estate | 2008 |
| Holt Solutions Limited | Hospitality | 2001 |
| Holy Greens UK Ltd | Hospitality | 2025 |
| Home & Garden Centre Limited | Wholesale & retail | 2000 |
| Home and DRY Construction Ltd | Construction | 2018 |
| Home Farm Close (Lighthorne) Management Company Limited | Households | 2020 |
| Home to Home Care Services Ltd | Health & social care | 2018 |
| Homebass Ltd | Manufacturing | 2023 |
| Homesabroad.Uk.Com Limited | Real estate | 1999 |
| Homesbuild Ltd | Construction | 2015 |
| Hone Rugs Limited | Wholesale & retail | 2015 |
| Honest Catering Limited | Extraterritorial | 2015 |
| Hooper & Co International Trade Consultancy Ltd | Administrative & support | 2017 |
| Hope Summers Communications Limited | Professional & scientific | 2013 |
| Hopkins Interiors Limited | Construction | 2025 |
| Horizon Sourcing Ltd | Real estate | 2017 |
| Horner Grand CRU Ltd | Professional & scientific | 2024 |
| Horner's Homes Ltd | Real estate | 2018 |
| Hostaway UK Limited | Information & communication | 2023 |
| Hot TUB Rescue Ltd | Other services | 2025 |
| Hotel Assistance Limited | Hospitality | 2020 |
| House Estates Limited | Real estate | 2021 |
| House of British Bonsai and Yamadori (Hobby) Ltd | Wholesale & retail | 2024 |
| House of Hair (Warwick) Limited | Other services | 2024 |
| House of Harris Interiors Limited | Professional & scientific | 2021 |
| House of Laser Warwick Limited | Other services | 2014 |
| Housed Ltd | Real estate | 2025 |
| Housestyle Countrywide (Clarendon) Limited | Real estate | 2022 |
| Housestyle Countrywide (Lighthorne) Ltd | Households | 2015 |
| Housestyle Countrywide (Newbold Terrace) Limited | Households | 2017 |
| Housestyle Countrywide (Oxford Street) Limited | Households | 2016 |
| Housestyle Countrywide (Spring Acre) Limited | Households | 2016 |
| Houterman Smith Properties Limited | Construction | 2020 |
| Howcas Limited | Real estate | 2004 |
| Hoxhunt Limited | Information & communication | 2019 |
| Hoyco Limited | Information & communication | 2001 |
| Hpcimpact Limited | Information & communication | 2023 |
| HRH Rentals Ltd | Hospitality | 2025 |
| HRP ERP Solutions Limited | Information & communication | 2010 |
| HS Renewables Ltd | Construction | 2022 |
| HSI Transport Ltd | Transport & logistics | 2023 |
| HSM Consulting Limited | Professional & scientific | 2023 |
| Hstl Made Ltd | Wholesale & retail | 2017 |
| Hughes & Hughes Legal Services Limited | Administrative & support | 2022 |
| Hugolicious Limited | Wholesale & retail | 2025 |
| Hulco U.K. Limited | Manufacturing | 1984 |
| Hull Property Investments Limited | Real estate | 2005 |
| Humber Consulting Limited | Information & communication | 2019 |
| Humber Hydrogen Transmission System Ltd | Financial services | 2024 |
| Hunneybell-Evans Limited | Financial services | 2008 |
| Huscarl Training Ltd | Education | 2025 |
| Hy-Kleen of Warwick Limited | Administrative & support | 1994 |
| Hydrive Ltd | Professional & scientific | 2024 |
| Hydrogen Engineering Enhancing Technology Ltd | Water & waste | 2014 |
| Hydromotive Ltd | Professional & scientific | 2024 |
| Hype Ltd | Information & communication | 2010 |
| Hzimmerman Holding Limited | Financial services | 2022 |
| I G a Certification Limited | Wholesale & retail | 2007 |
| I&Rac Infrastructures Limited | Administrative & support | 2024 |
| I3I Distribution Limited | Wholesale & retail | 2009 |
| I3I Group Limited | Administrative & support | 2013 |
| I3I Solutions Limited | Information & communication | 2010 |
| I3I Systems Limited | Wholesale & retail | 2013 |
| I4SEA Technologies Limited | Professional & scientific | 2021 |
| Iambic Therapeutics UK Ltd | Information & communication | 2020 |
| IAN Crockett Motors Ltd | Wholesale & retail | 2003 |
| Iaps | Education | 1923 |
| Iaps Charitable Trust | Education | 2011 |
| Iaps Consultancy Ltd | Professional & scientific | 2021 |
| Iberian Art Limited | Hospitality | 2014 |
| IBI (Design) Limited | Construction | 2010 |
| IBJ Ltd | Construction | 2025 |
| Ibware Technologies Ltd | Information & communication | 2022 |
| Iceo LAB Ltd | Information & communication | 2018 |
| Iconix Design Limited | Other services | 2008 |
| ICT Solutions (UK) Limited | Information & communication | 2008 |
| Ideal Bathrooms (Wolseley) Limited | Wholesale & retail | 2022 |
| Ideas by Design Limited | Administrative & support | 1996 |
| Ideas LAB Ltd | Professional & scientific | 2024 |
| Ideation LAB Ltd | Real estate | 2025 |
| Idktp Ltd | Financial services | 2023 |
| IJ Beverages Ltd | Wholesale & retail | 2026 |
| IK Insights Limited | Professional & scientific | 2026 |
| IK Tech Limited | Professional & scientific | 2005 |
| Iksh Ltd | Real estate | 2025 |
| IL Piccolino's Limited | Hospitality | 2005 |
| Ilarna Foundation Limited | Other services | 2024 |
| Illegally Blonde (Management) Ltd | Other services | 2025 |
| Illustrated Ltd | Education | 2017 |
| IM Design Limited | Professional & scientific | 2014 |
| Imagemaker Digital Limited | Information & communication | 2021 |
| Imaginari Design Ltd | Professional & scientific | 2023 |
| Imagine Engineering Limited | Administrative & support | 2012 |
| Imagineall Ltd | Real estate | 2017 |
| Imaginera Holdings Limited | Financial services | 2024 |
| Imaginera Limited | Information & communication | 2013 |
| IMJ Management Consulting Ltd | Professional & scientific | 2012 |
| Imja Group Limited | Financial services | 2016 |