| Housing Professionals Limited | Real estate | 2000 |
| Houslet Limited | Real estate | 2019 |
| Hoverkart Mania Ltd | Arts & recreation | 2019 |
| Howards Decorators (North West) Ltd | Construction | 2016 |
| Howe & Coates Limited | Wholesale & retail | 1993 |
| Howe Ventures Ltd | Other services | 2025 |
| HPH Properties Limited | Real estate | 2016 |
| HQ Investments Limited | Real estate | 2016 |
| HR on Hand Ltd | Professional & scientific | 2009 |
| HRC Rigging Ltd | Transport & logistics | 2015 |
| HS Civils Solutions Ltd | Construction | 2025 |
| HS Power Properties Limited | Real estate | 2025 |
| HS Power Solutions Ltd | Construction | 2022 |
| Hudora Pet Hotel Limited | Agriculture & fishing | 2002 |
| Hudson and SON Limited | Construction | 2015 |
| Hughes Estate Agents Limited | Real estate | 2011 |
| Hughes Financial Solutions Limited | Financial services | 2009 |
| Hughes Haulage (Chorley) Ltd | Transport & logistics | 2009 |
| Hulton Estates Limited | Professional & scientific | 2007 |
| Humansetc Ltd | Information & communication | 2018 |
| Hungaro-Cargo Limited | Transport & logistics | 2012 |
| Hunt Minas Wealth Management Ltd | Financial services | 2012 |
| Hunter Building Services (Lancs) Ltd | Construction | 2022 |
| Hunter Fuel Solutions Limited | Administrative & support | 2019 |
| Hunter Investigations Ltd | Administrative & support | 2024 |
| Hunter Property Group (Lancs) Ltd | Construction | 2026 |
| Hunter Surveillance Services Ltd | Administrative & support | 2018 |
| Hurford Properties Limited | Real estate | 2019 |
| Hurst & Co Property Services Ltd | Construction | 2015 |
| Hushabye Hands Ltd | Education | 2014 |
| Hussain Retail Ltd | Wholesale & retail | 2023 |
| HVM North Limited | Real estate | 2017 |
| HW Legal Consulting Limited | Professional & scientific | 2023 |
| Hybrid Fitness League Ltd | Information & communication | 2026 |
| Hyde's Group Holdings Limited | Financial services | 2018 |
| Hyde's Toys & Gifts Limited | Wholesale & retail | 2006 |
| Hydro Bidco Limited | Financial services | 2023 |
| Hydro Midco Limited | Financial services | 2023 |
| Hydro Topco Limited | Financial services | 2023 |
| Hydrodoor Europe Ltd | Manufacturing | 2017 |
| Hygienic Maintenance Services Ltd | Administrative & support | 2021 |
| Hypothetic Ltd | Information & communication | 2026 |
| Hyrox Preston Limited | Other services | 2022 |
| Hyspec Joinery Ltd | Construction | 2022 |
| Hyspex Limited | Professional & scientific | 2018 |
| Hywel Ltd | Information & communication | 2021 |
| I & J Meats Limited | Wholesale & retail | 2012 |
| I Bloom YOU Ltd | Wholesale & retail | 2025 |
| I E B Consulting Limited | Construction | 2001 |
| I Own Limited | Professional & scientific | 2019 |
| I W Critchley & SON Limited | Wholesale & retail | 2009 |
| I W J Services Limited | Transport & logistics | 2010 |
| I Want That Camera Ltd | Other services | 2025 |
| I Watson Haulage Limited | Transport & logistics | 2010 |
| I-Sunglasses Limited | Wholesale & retail | 2009 |
| I. P. Jones Fencing Contractors Limited | Construction | 2000 |
| I.H. Psychotherapy Services Ltd | Health & social care | 2025 |
| IA Logistics Ltd | Information & communication | 2019 |
| IAN Southcott Ltd | Professional & scientific | 2019 |
| IAN Williams Garden Services Ltd | Administrative & support | 2013 |
| IBA Enterprises Limited | Financial services | 2019 |
| IBA GAS Maintenance Limited | Construction | 2011 |
| Ibathrooms & Boilers UK Ltd | Construction | 2020 |
| Ibbotson Transport Limited | Transport & logistics | 2006 |
| Ice Adventure Limited | Arts & recreation | 2009 |
| Iced Digital Ltd | Information & communication | 2021 |
| Icib Investments Ltd | Financial services | 2023 |
| Iconoclast 22 Limited | Professional & scientific | 2022 |
| Iddon Development Ltd | Information & communication | 2025 |
| Identity Furniture Limited | Wholesale & retail | 2002 |
| Identity Group Ltd | Financial services | 2016 |
| IDR Investments NW Ltd | Real estate | 2022 |
| IF Apparel Limited | Wholesale & retail | 2019 |
| IFS Worthing Ltd | Other services | 2019 |
| IG Kleans Ltd | Administrative & support | 2025 |
| IG Medical Limited | Health & social care | 2015 |
| IGC Engineering Limited | Professional & scientific | 2002 |
| IGC Engineering Systems Limited | Other services | 2023 |
| IGC Group 2020 Limited | Financial services | 2020 |
| Igloo Construction Limited | Construction | 2003 |
| Ihelm Enterprises Limited | Information & communication | 2004 |
| IIL Holdings Limited | Financial services | 2024 |
| Ikon Interior Contracts Ltd | Manufacturing | 2017 |
| Ikon Stone Ltd | Transport & logistics | 2013 |
| Ilanga Photography Limited | Arts & recreation | 2011 |
| ILDT4 Ltd | Hospitality | 2019 |
| Ilforall Ltd | Real estate | 2023 |
| ILM Medical Limited | Health & social care | 2023 |
| Ilona Investments Limited | Real estate | 2023 |
| Ilpg Ltd | Extraterritorial | 2012 |
| Image Associates Limited | Information & communication | 2000 |
| Imaginary Friends Brewing Limited | Manufacturing | 2018 |
| Imagiprint Ltd | Manufacturing | 2024 |
| Imap Vehicle Solutions Limited | Wholesale & retail | 2026 |
| Imeg Partnership Limited | Professional & scientific | 2022 |
| Immersive Property Group Ltd | Administrative & support | 2023 |
| Impact Plants Ltd | Administrative & support | 2015 |
| Impact Research and Evaluation Limited | Professional & scientific | 2022 |
| Impact Socket Supplies Limited | Wholesale & retail | 1972 |
| Impact Vehicle Management Ltd | Wholesale & retail | 2011 |