| Help ! Build ME Ltd | Professional & scientific | 2024 |
| Hels Boutique Ltd | Wholesale & retail | 2025 |
| Helsbells Bounce and Play Ltd | Arts & recreation | 2025 |
| Hendy HR Limited | Administrative & support | 2020 |
| Hendy Property Management Limited | Real estate | 2021 |
| Herbert Garland Group Ltd | Financial services | 2025 |
| Heritage Gate Estate Ltd | Real estate | 2010 |
| Heritage Masonry Group Limited | Manufacturing | 2025 |
| Highbury Court Management Limited | Real estate | 1988 |
| Highgate Bespoke Renovations Ltd | Construction | 2025 |
| Hilbar Auto's Limited | Wholesale & retail | 2010 |
| Hitchit UK Ltd | Wholesale & retail | 2019 |
| HK Barber Limited | Other services | 2018 |
| HLW Kitchen Wizard Limited | Construction | 2014 |
| Hobbl Ltd | Information & communication | 2022 |
| Hodges Transport Ltd | Transport & logistics | 2022 |
| Holiday House (Meifod) Ltd | Hospitality | 2020 |
| HOME2WALES Ltd | Construction | 2024 |
| Homecare Safeguard Ltd | Construction | 2022 |
| Hooper's Eco Play-Cafe Ltd | Extraterritorial | 2012 |
| Hopkin’S Butchers (Neath) Limited | Wholesale & retail | 2025 |
| Horizon GB Holdings Ltd | Real estate | 2025 |
| House to Home Property Sales & Renovations Ltd | Real estate | 2024 |
| Housecallbeauty Ltd | Other services | 2026 |
| Houses of Light Ltd | Administrative & support | 2012 |
| Howard Evans Financial Services Limited | Financial services | 2005 |
| Hpsa 11 Limited | Hospitality | 2026 |
| Hslg Limited | Professional & scientific | 2014 |
| HT Law Limited | Professional & scientific | 2011 |
| HTT Connect Limited | Education | 2026 |
| Humanity Global Housing Ltd | Real estate | 2017 |
| Hungry Rebel Holdings Ltd | Financial services | 2025 |
| Hutchinson Thomas Limited | Professional & scientific | 2011 |
| Hvsubsol Ltd | Construction | 2024 |
| I Care Health Group Ltd. | Health & social care | 2016 |
| I L E Homes Ltd | Real estate | 2025 |
| I L Vehicle Rentals Limited | Hospitality | 2019 |
| I.M. Design Studio Ltd | Professional & scientific | 2020 |
| I.Taylor Enterprises Ltd | Construction | 2018 |
| IAN Ross Group Limited | Financial services | 2025 |
| IAN Ross Investments Limited | Real estate | 2025 |
| IAN Ross Ventures Limited | Financial services | 2025 |
| IBM Brickwork Ltd | Construction | 2020 |
| Iced Recoveries Limited | Health & social care | 2023 |
| Ideal Designs Home Improvements Ltd | Wholesale & retail | 2019 |
| Idndt Inspections Ltd | Manufacturing | 2018 |
| Iengineer Consultancy Ltd | Professional & scientific | 2022 |
| Ilash Shan Products Ltd | Wholesale & retail | 2020 |
| Ilayda Stays Ltd | Hospitality | 2024 |
| Imaginedit Limited | Information & communication | 2025 |
| Imex Imports Ltd | Wholesale & retail | 2018 |
| Independent Buyer.Net Limited | Administrative & support | 2006 |
| Independent Medcare Ltd | Health & social care | 2021 |
| Infinite Blue Property Group UK Limited | Real estate | 2017 |
| Ingoodnic Group Ltd | Financial services | 2020 |
| Ingoodnic Ltd | Administrative & support | 2011 |
| Insight Health Screening Limited | Health & social care | 2009 |
| Instrument and Control Solutions Limited | Professional & scientific | 2005 |
| Intelligent Tracking Limited | Information & communication | 2018 |
| Investerties Ltd | Real estate | 2024 |
| Investment and Funding Limited | Professional & scientific | 2012 |
| Istratis Procurement Services Limited | Professional & scientific | 2024 |
| ITK Reporting Ltd | Information & communication | 2026 |
| Itrl Limited | Professional & scientific | 2021 |
| Ivory and Bloom Ltd | Information & communication | 2026 |
| J & D Clarke Limited | Financial services | 2010 |
| J & L Games Ltd | Arts & recreation | 2019 |
| J G Hale Group Ltd | Construction | 2013 |
| J G Jones (Kitchen Installations) Limited | Construction | 2004 |
| J James Upvc Ltd | Construction | 2020 |
| J Jones Landscapes Limited | Administrative & support | 2024 |
| J M Evans Building Limited | Construction | 2025 |
| J Paul Jones Ltd | Transport & logistics | 2025 |
| J Shaw's Property Maintenance Ltd | Construction | 2023 |
| J T Roberts Associates Limited | Professional & scientific | 2012 |
| J V Formwork Ltd | Construction | 2026 |
| J&D Enterprise Limited | Real estate | 2026 |
| J'S Cafe & Desserts Limited | Hospitality | 2022 |
| J-Graham Hale Limited | Administrative & support | 1996 |
| J. Adderley Properties Limited | Real estate | 2025 |
| J. D. C. Developments Ltd. | Construction | 1999 |
| J. Gethin Limited | Other services | 2007 |
| J.G. Hale Construction Limited | Construction | 1999 |
| J.M. Wealth Planning Limited | Financial services | 2016 |
| J.Phillips NDT Limited | Professional & scientific | 2019 |
| J.W. & S.M. Property Ltd | Real estate | 2018 |
| J43 Design Limited | Manufacturing | 2001 |
| JA Removals Limited | Transport & logistics | 2025 |
| JAB Offshore Ltd | Administrative & support | 2025 |
| Jack's Clearances Ltd | Water & waste | 2022 |
| Jacky's Vending Limited | Wholesale & retail | 2006 |
| Jahan Estates Ltd | Hospitality | 2025 |
| James Brothers Plumbing and Property Renovation Ltd | Construction | 2019 |
| James Brothers Roofing Limited | Construction | 2026 |
| James Brothers Waste and Garden Ltd | Water & waste | 2021 |
| Jamiesproperties Limited | Real estate | 2023 |
| Janela Shutters Limited | Manufacturing | 2014 |
| Japanese Knotweed Elimination Ltd | Administrative & support | 2015 |
| Jason Wright Ltd | Construction | 2023 |
| Jawa Kombucha Ltd | Manufacturing | 2018 |