| Hopepunk Ltd | Professional & scientific | 2025 |
| Hopkins Court Management Company Limited | Households | 1995 |
| Host Smart Ltd | Real estate | 2023 |
| Hosting Homes Limited | Real estate | 2018 |
| Hostsmart Investment Portfolio Ltd | Hospitality | 2025 |
| Hot Innovations Ltd | Hospitality | 2003 |
| Hot Moves Limited | Transport & logistics | 2023 |
| Hot Tanning Ltd | Other services | 2025 |
| Hotels With Heart Limited | Administrative & support | 2025 |
| Houdret & Company Limited | Other services | 1973 |
| House of Hamble Limited | Construction | 2013 |
| House of Persia Limited | Hospitality | 2019 |
| House of Tyres Ltd | Wholesale & retail | 2017 |
| Howard Hungerford Limited | Financial services | 2020 |
| Hoxton Design Ltd | Professional & scientific | 2025 |
| Hoxton Distributions Limited | Wholesale & retail | 2022 |
| Hoxton Vodka Limited | Extraterritorial | 2024 |
| HPW Associates Limited | Professional & scientific | 2014 |
| HR Pilot Services Ltd | Transport & logistics | 2023 |
| Humid Music Limited | Arts & recreation | 2018 |
| Humphreys of Henley Limited | Wholesale & retail | 2012 |
| Hunt Lancaster Limited | Information & communication | 1999 |
| Hunts Farm Residents Management Company Limited | Households | 2019 |
| Hurley Burley Partners Ltd | Administrative & support | 2018 |
| Hurst Sanderson LLP | | 2011 |
| HV Aviation Limited | Transport & logistics | 2021 |
| Hyde END Road Development Ltd | Construction | 2018 |
| Hypergallery Ltd | Wholesale & retail | 2002 |
| Iaconnects Technology Limited | Professional & scientific | 2004 |
| IBS Office Solutions Limited | Administrative & support | 2006 |
| ID41 Limited | Professional & scientific | 2012 |
| Iguazu Midco 1 Limited | Financial services | 2021 |
| Imedge Ltd | Information & communication | 2017 |
| Imma Group Limited | Manufacturing | 2021 |
| Immy Pops Limited | Financial services | 2021 |
| Impel Facilities Management Limited | Administrative & support | 2016 |
| Imperial Square (Binfield) Management Company Limited | Households | 2016 |
| Impressive Ideas Limited | Professional & scientific | 1998 |
| IN Showjumpers Global Limited | Agriculture & fishing | 2018 |
| IN8WEB Ltd | Information & communication | 2006 |
| Inbeta Limited | Information & communication | 2020 |
| Incore Physiotherapy Services Ltd | Health & social care | 2025 |
| Independent Director Services Limited | Professional & scientific | 2003 |
| Indica Consultancy Limited | Administrative & support | 2010 |
| Indivity Limited | Information & communication | 2002 |
| Indypol Properties Limited | Real estate | 2022 |
| Influential Computers Limited | Information & communication | 1984 |
| Infra Vest Limited | Construction | 2023 |
| Infraspec Ltd | Other services | 2017 |
| Infrastructure Ventures Limited | Professional & scientific | 2010 |
| Ingleby Barwick Golf Academy Limited | Hospitality | 2005 |
| Ingxabo International Ltd | Health & social care | 2017 |
| Innings Gate Residents Association Limited | Real estate | 2020 |
| Innovatium Services Ltd | Professional & scientific | 2018 |
| Inside Edge Power Limited | Professional & scientific | 2024 |
| Inspiratio Limited | Wholesale & retail | 2021 |
| Inspire Design and Build Ltd | Administrative & support | 2011 |
| Intelligent Healing Limited | Professional & scientific | 2008 |
| Intrepid Marketing Limited | Professional & scientific | 2015 |
| Invesco (Nominees) Limited | Extraterritorial | 1984 |
| Invesco Asset Management Limited | Financial services | 1969 |
| Invesco FAR East Limited | Professional & scientific | 1997 |
| Invesco Fund Managers Limited | Financial services | 1967 |
| Invesco GT Asset Management Limited | Professional & scientific | 1969 |
| Invesco Holding Company Limited | Financial services | 1935 |
| Invesco International Holdings Limited | Financial services | 1982 |
| Invesco Pacific Group Limited | Financial services | 1994 |
| Invesco Pension Trustees Limited | Professional & scientific | 1994 |
| Invesco UK Holdings Limited | Financial services | 1989 |
| Invesco UK Limited | Financial services | 1994 |
| Invesco UK Services Limited | Financial services | 2008 |
| Investmaster Limited | Professional & scientific | 2001 |
| Irja Howie's Content Company Limited | Information & communication | 2024 |
| Iron Triple Consulting Limited | Information & communication | 2011 |
| Ironbridge Capital Partners LLP | | 2004 |
| Ithaca Infrastructure Limited | Professional & scientific | 2019 |
| J Builders and Landscape Limited | Construction | 2025 |
| J C Dental Care Ltd | Health & social care | 2018 |
| J F Clarke Consulting Limited | Professional & scientific | 2015 |
| J G Motor Services Limited | Wholesale & retail | 2020 |
| J G Seaton Consulting Ltd | Professional & scientific | 2022 |
| J Maillard Trading Limited | Hospitality | 2018 |
| J Penney Services Limited | Extraterritorial | 2022 |
| J Simons Events Ltd | Hospitality | 2021 |
| J Stanton Consultants Ltd | Professional & scientific | 2024 |
| J&C Influence Ltd | Professional & scientific | 2025 |
| J.Evans Property Services Limited | Construction | 2022 |
| J.M Motor Trade Limited | Wholesale & retail | 2023 |
| J.M Property Holdings Ltd | Construction | 2022 |
| J.T. Davies & Sons Holdings Limited | Professional & scientific | 2006 |
| J.T.D. Finance Limited | Administrative & support | 2006 |
| J.T.D. Investments Limited | Administrative & support | 2006 |
| J.T.Davies & Sons Limited | Hospitality | 1911 |
| Jacksmeadow (Uffington) Management Company Limited | Real estate | 2016 |
| Jackson Rose Recruitment Solutions Limited | Administrative & support | 2006 |
| Jacob Simons Limited | Professional & scientific | 2022 |
| Jacobcx Development Ltd | Information & communication | 2020 |
| Jade Global Holdings Limited | Financial services | 2020 |
| Jake Kemp Ltd | Information & communication | 2024 |
| James Bryant Limited | Professional & scientific | 1930 |