| Hilton Storage Limited | Transport & logistics | 2015 |
| Hippy Shop Limited | Wholesale & retail | 2018 |
| Historic Retreats Ltd | Hospitality | 2019 |
| Hitchcock Engineering Ltd. | Construction | 2002 |
| Hitchetts Hill Trading Limited | Wholesale & retail | 2018 |
| HJB Property Ltd | Real estate | 2025 |
| Hlengineering Ltd | Manufacturing | 2025 |
| Hoang GIA Ltd | Hospitality | 2023 |
| Hoang Phat Nail Limited | Other services | 2024 |
| Hobah Equestrian Limited | Information & communication | 2024 |
| Hoddy's Limited | Manufacturing | 2020 |
| Hodgins and Rayner Ltd | Hospitality | 2024 |
| HOE Grange Holidays Limited | Hospitality | 2018 |
| Holbrook Advisory Ltd | Professional & scientific | 2024 |
| Hollywood ST MX Ltd | Arts & recreation | 2022 |
| Hooper Engineering Ltd | Professional & scientific | 2019 |
| Hope Farm Holidays Ltd | Hospitality | 2021 |
| Hope Project - Helping Pupils' & Parents Emotional Wellbeing CIC | Education | 2022 |
| Horizon Adventure Breaks Limited | Education | 2025 |
| Hornbeam Associates Limited | Administrative & support | 2005 |
| Hotels and Venues Limited | Administrative & support | 2010 |
| Hotshotcreative LLP | | 2016 |
| Hoults Plumbing and Heating Limited | Construction | 2021 |
| HOUSE2HOME Conveyancing Ltd | Professional & scientific | 2023 |
| Housley CAD Services Limited | Information & communication | 2002 |
| Howardson Group Hire Ltd | Administrative & support | 2024 |
| Howe to Recycle Ltd | Water & waste | 2020 |
| HTH Transport Ltd | Transport & logistics | 2016 |
| HUI Property Group Ltd | Real estate | 2020 |
| Hulland Capital 4 Limited | Other services | 2017 |
| Hulland Capital 5 Limited | Other services | 2017 |
| Hulland Capital Developments Ltd | Other services | 2019 |
| Hulland House Ltd | Hospitality | 2019 |
| Hulland Nurseries Ltd | Agriculture & fishing | 2019 |
| Hulland Property Company Limited | Real estate | 1996 |
| Hunter Industrial Services Ltd | Professional & scientific | 2025 |
| Hydraulics UK Ltd | Extraterritorial | 1998 |
| I & C a Potter Ltd | Administrative & support | 2026 |
| I B Building Contractors Limited | Construction | 2009 |
| I Booked IT Ltd | Information & communication | 2014 |
| I Matkin Joinery Ltd | Construction | 2026 |
| IAN Harrison Transport Limited | Transport & logistics | 2003 |
| IAN Potter Marketing Services Limited | Administrative & support | 2010 |
| ICA Communications Limited | Professional & scientific | 2000 |
| Icarus Collective Ltd | Administrative & support | 2001 |
| IGF Decor Limited | Construction | 2003 |
| IGM Project Solutions Limited | Professional & scientific | 2004 |
| Ikigai Retreats Ltd | Hospitality | 2026 |
| Ikry Ltd | Wholesale & retail | 2026 |
| Imac Projects Ltd | Construction | 2020 |
| Imagetotal Limited | Real estate | 1990 |
| IN 21 Limited | Information & communication | 1999 |
| Infinity for Eternity Ltd | Real estate | 2011 |
| Inishowen Consulting Limited | Professional & scientific | 2024 |
| Inizio Design Limited | Arts & recreation | 2014 |
| Inkjet & Printing Supplies Limited | Wholesale & retail | 2002 |
| Inner Direction Ltd | Professional & scientific | 2019 |
| Inovello Consulting Limited | Professional & scientific | 2013 |
| Insight Coaching Solutions Ltd | Administrative & support | 2017 |
| Inspect-A-Drain Limited | Administrative & support | 2002 |
| Inspiral Fashion Limited | Wholesale & retail | 2015 |
| Integra Automation Systems Limited | Professional & scientific | 2001 |
| Interior Aspirations Limited | Extraterritorial | 2017 |
| Into Bikes Ltd | Wholesale & retail | 2011 |
| Investmap Limited | Information & communication | 2019 |
| IP 786 Ltd | Extraterritorial | 2023 |
| IRG Training & Services Limited | Transport & logistics | 2024 |
| IS Compliance Solutions Ltd | Information & communication | 2010 |
| Isac (UK) Limited | Administrative & support | 2002 |
| Isey & Co Limited | Other services | 2011 |
| ISULU2 Limited | Wholesale & retail | 2022 |
| Ivanhoe (Ashby) Management Company Ltd | Real estate | 2005 |
| Ivanhoe Business Park (a to D) Management Company Ltd | Real estate | 2015 |
| Ixion Technology Ltd | Information & communication | 2022 |
| J & a Straw Products Ltd | Manufacturing | 2025 |
| J & L POT Limited | Agriculture & fishing | 2002 |
| J & S Holmes LLP | | 2021 |
| J a Crooks Building Ltd | Construction | 2026 |
| J a S Agricultural (UK) Limited | Agriculture & fishing | 2005 |
| J and S Plumbing, Heating and GAS Services Limited | Construction | 2014 |
| J E Barker Ltd | Construction | 2018 |
| J H Holidays Ltd | Real estate | 2026 |
| J O Smith Ltd | Agriculture & fishing | 2003 |
| J R T Construction Limited | Construction | 1999 |
| J S Oakley Estate Limited | Financial services | 2019 |
| J Young Engineering Services Ltd | Construction | 2011 |
| J&R Management Ltd | Real estate | 2012 |
| J. B. Joinery and Building Limited | Construction | 2006 |
| J.A Property Renovations Ltd | Construction | 2024 |
| J.C.Archer Limited | Agriculture & fishing | 1958 |
| J.D.B. Groundworks & Surfacing Ltd | Construction | 2009 |
| Jaftica Ltd | Professional & scientific | 2026 |
| JAM ENTERPRISES25 Ltd | Hospitality | 2025 |
| JAM Thornley Ltd | Wholesale & retail | 2012 |
| James Brown Groundworks Limited | Construction | 2020 |
| James Roobottom Traditional Building and Renovation Limited | Construction | 2022 |
| Jamhaus Community Music Hub CIC | Education | 2026 |
| Jamhaus Music Ltd | Wholesale & retail | 2024 |
| Jamie Edwards Building Limited | Construction | 2002 |
| Jasmine House Rentals Ltd | Real estate | 2023 |