| GWG Waste Care Solutions UK Ltd | Water & waste | 2013 |
| H L Joinery Ltd | Construction | 2008 |
| H.E.E.P (UK) (Heal, Empower, Educate, Prevent) Community Interest Company | Education | 2025 |
| H2 Property Investments Limited | Administrative & support | 2004 |
| H2GLENFERN Limited | Professional & scientific | 2003 |
| Habilis Garden Lifestyle Ltd | Professional & scientific | 2025 |
| Haines Gadd Greaves Limited | Professional & scientific | 2018 |
| Halden Dash Ltd | Information & communication | 2008 |
| Hall Financial Planning LLP | | 2009 |
| Halle Housing Ltd | Real estate | 2024 |
| Haralina Ltd | Real estate | 2019 |
| Harbour Neuro Ltd | Professional & scientific | 2026 |
| Harmony Medical Distribution Limited | Wholesale & retail | 1987 |
| Harrisons Aesthetics Skincare Clinic Ltd | Other services | 2023 |
| Harrisons Car Sales Ltd | Wholesale & retail | 2022 |
| Harrisons Fish & Chips Ltd | Hospitality | 2020 |
| Hartham Park Minerals Limited | Real estate | 2017 |
| Harvey Holland Limited | Real estate | 2019 |
| Harwood Automotive Ltd | Extraterritorial | 2021 |
| Harwood Residential Ltd | Real estate | 2024 |
| Have YOU Heard Limited | Professional & scientific | 2017 |
| Hawes & Sons (Cirencester) Limited | Professional & scientific | 1973 |
| Hbeb Services Ltd | Professional & scientific | 2022 |
| HBP Residual Property Limited | Construction | 2019 |
| HC Wychwood Management Ltd | Real estate | 2022 |
| HCP Farming Ltd | Agriculture & fishing | 2019 |
| Health AI Ltd | Health & social care | 2024 |
| Health Bonus Ltd | Wholesale & retail | 2011 |
| Healthpack Limited | Health & social care | 2016 |
| Healthpack Logistics Limited | Wholesale & retail | 2008 |
| Healthy Beast Equine Ltd | Agriculture & fishing | 2014 |
| Healthy Beast Limited | Arts & recreation | 2024 |
| Heathwold Security Services Ltd | Administrative & support | 2024 |
| Heavenly Trees Ltd | Agriculture & fishing | 2019 |
| Henda Knobel Design Ltd | Professional & scientific | 2021 |
| Henderson Project Consultancy Ltd | Professional & scientific | 2019 |
| Henry Stratford Consulting Ltd | Professional & scientific | 2020 |
| Henry Street Property Company Limited | Construction | 1966 |
| Heritage Quarry Group (North) Limited | Mining & quarrying | 2022 |
| Heritage Quarry Group (South) Limited | Mining & quarrying | 2020 |
| Hesterra Ltd | Administrative & support | 2022 |
| Hibiscus Five Limited | Real estate | 2017 |
| Hibiscus Seven Ltd | Real estate | 2026 |
| Hibiscus SIX Limited | Real estate | 2021 |
| Hickman Brothers Landscapes Limited | Construction | 1990 |
| High Lodge Fungi Limited | Agriculture & fishing | 2023 |
| Hillrock Limited | Manufacturing | 2026 |
| Hillyjo Ltd | Wholesale & retail | 2016 |
| Hitchman Utilities Ltd | Real estate | 2025 |
| Hitchmans Ltd | Wholesale & retail | 2016 |
| HM Personal Training Ltd | Health & social care | 2023 |
| HMD Europe Ltd | Wholesale & retail | 1991 |
| Hobbs Hole Limited | Agriculture & fishing | 2008 |
| Hoco Trans Limited | Transport & logistics | 2018 |
| Holy Social Ltd | Professional & scientific | 2019 |
| Home Farm (Over Norton) Limited | Real estate | 2005 |
| Home Farm Properties (Little Preston) Limited | Financial services | 2022 |
| Homename Limited | Financial services | 1989 |
| Honeyway Construction Limited | Construction | 2007 |
| Hook Norton Equine Ltd | Agriculture & fishing | 2021 |
| Horsehay Farm and Leisure Limited | Hospitality | 2021 |
| Housemission Limited | Construction | 2001 |
| Hozts Ltd | Information & communication | 2020 |
| Hstjc Ltd | Professional & scientific | 2019 |
| HTP Aviation Services Ltd | Manufacturing | 2018 |
| Hudson Cubed Limited | Arts & recreation | 2016 |
| Hugh Wassell Ltd | Construction | 2010 |
| Hugopickering.Com Limited | Professional & scientific | 2015 |
| Hundred Acres Apothecary Limited | Wholesale & retail | 2013 |
| Huntley Spence Limited | Administrative & support | 2009 |
| Hurlingham Capital Limited | Real estate | 2009 |
| HV Senior Authorised Solutions Ltd | Construction | 2025 |
| I AM a Graduate Limited | Extraterritorial | 2006 |
| I C Pearman Limited | Wholesale & retail | 1979 |
| I.G. Carpentry and Joinery Specialists Limited | Construction | 1997 |
| IAN Stedman Coaching Limited | Arts & recreation | 2023 |
| Ibbotson Studios Limited | Professional & scientific | 2013 |
| Iberian Horses Limited | Wholesale & retail | 2024 |
| IBX Ltd | Information & communication | 2012 |
| Icon Scaffolding Ltd | Construction | 2010 |
| Idexqr Ltd | Administrative & support | 2025 |
| Ie-Ndt Limited | Manufacturing | 2000 |
| Ignition Agencies Limited | Wholesale & retail | 2024 |
| Iley Design Limited | Professional & scientific | 2015 |
| Illions Limited | Professional & scientific | 2002 |
| Impact Advertising & Design Limited | Professional & scientific | 1987 |
| Indigo Consulting Solutions Limited | Information & communication | 2007 |
| Infologic Ltd | Information & communication | 2005 |
| Informed Decision Limited | Professional & scientific | 2003 |
| Innerise Wellbeing Ltd | Health & social care | 2025 |
| Innopack Ltd | Professional & scientific | 2024 |
| Inparlour Ltd | Arts & recreation | 2012 |
| Insuremy Limited | Extraterritorial | 2005 |
| Insuremybusiness Limited | Extraterritorial | 2005 |
| Insuremycar Limited | Extraterritorial | 2005 |
| Insuremyholiday Limited | Extraterritorial | 2005 |
| Insuremyhome Limited | Extraterritorial | 2005 |
| Intel Force Ltd | Information & communication | 2026 |
| Intime Properties Limited | Real estate | 2014 |
| IP Pro Limited | Administrative & support | 2018 |