| Heritage House Diagnostics Ltd | Financial services | 2026 |
| Herriard Cyder Co Limited | Manufacturing | 2024 |
| Herriard Hound Hotel Limited | Other services | 2024 |
| Heslop Digital Ltd | Information & communication | 2013 |
| Hetty Verney Associates Ltd | Professional & scientific | 2018 |
| Hewgar House Limited | Information & communication | 2020 |
| Hewgar House Property Limited | Real estate | 2025 |
| Hexaxes Ltd | Professional & scientific | 2024 |
| Heynes Properties Limited | Real estate | 2017 |
| HF Property Finding Ltd | Real estate | 2024 |
| Hgvdriversuk Limited | Transport & logistics | 2017 |
| HH Global Interactive Limited | Information & communication | 2000 |
| HI Spirits Bar Co Ltd | Hospitality | 2019 |
| High Tide Leap Ltd | Professional & scientific | 2022 |
| Highfield Partners Ltd | Real estate | 2021 |
| Highmoor + Frieth Properties Ltd | Construction | 2024 |
| Hijacknet Limited | Information & communication | 2014 |
| Hilles House Weddings Limited | Hospitality | 2022 |
| Hills Building & Architectural Services Limited | Construction | 2007 |
| Hillside (Cirencester) Limited | Real estate | 2020 |
| Hipermag Limited | Manufacturing | 2015 |
| Hiserve Computing Limited | Information & communication | 1989 |
| History Craft Limited | Manufacturing | 1975 |
| Hive CAM Limited | Administrative & support | 2018 |
| Hive Pension Ltd. | Financial services | 2024 |
| Hlcd Ltd | Information & communication | 2024 |
| HLX Ltd | Arts & recreation | 2016 |
| HM Tiling Ltd | Construction | 2022 |
| Hodgson Business Services Limited | Extraterritorial | 2015 |
| Holford Barns Management Company Limited | Real estate | 2000 |
| Holland & Bailey Limited | Financial services | 2018 |
| Hollow Management Company Limited | Households | 2001 |
| Holloway Bond Limited | Administrative & support | 2022 |
| Holly Robinson Ltd | Manufacturing | 2018 |
| Hollyhocks Book Shop Ltd | Wholesale & retail | 2026 |
| Home James Cirencester Limited | Transport & logistics | 2019 |
| Home Nations Hedging Ltd | Professional & scientific | 2025 |
| Home Paddock (Down Ampney) Ltd | Households | 2023 |
| Home-Start Cotswolds Ltd. | Education | 2005 |
| Honeydrop Property Management LLP | | 2025 |
| Hopper Roofing Services Limited | Construction | 2021 |
| Hornet Automotive Ltd | Wholesale & retail | 2022 |
| Horse & Groom Management Company Limited | Administrative & support | 2009 |
| Hortis Landscapes Limited | Administrative & support | 2021 |
| Hound Gate Ltd | Professional & scientific | 2018 |
| House of Sienna Ltd | Manufacturing | 2025 |
| House Transport Consultants Limited | Transport & logistics | 2016 |
| Howe Agricultural Services Limited | Manufacturing | 2003 |
| HR for Small Businesses Ltd | Administrative & support | 2014 |
| HRG Construction Limited | Construction | 2023 |
| Hseq Solutions Limited | Professional & scientific | 2007 |
| Hudson Creative Limited | Professional & scientific | 2003 |
| HUI HAO Limited | Hospitality | 2024 |
| Human Engineered Limited | Professional & scientific | 2022 |
| Human-Ai Systems Ltd | Wholesale & retail | 2020 |
| Hume Homes Ltd | Real estate | 2021 |
| Humphreys Property Management Limited | Households | 2026 |
| Hungerlands Limited | Agriculture & fishing | 2008 |
| Hunter Valley Sport Horses Ltd | Agriculture & fishing | 2016 |
| Hush Kitchens Ltd | Wholesale & retail | 2019 |
| Husk Data Ltd | Information & communication | 2022 |
| Huuser Limited | Hospitality | 2020 |
| HV Excavators Ltd | Construction | 2023 |
| HV Wrapping Ltd | Wholesale & retail | 2023 |
| HWM Building Services Limited | Construction | 2009 |
| Hyam Capital Partners Limited | Professional & scientific | 2020 |
| Hyams Autos Limited | Wholesale & retail | 1977 |
| Hydes Cyder Co LLP | | 2022 |
| Hydref Accounting Ltd | Professional & scientific | 2019 |
| Hydrophobe Ltd | Manufacturing | 2024 |
| Hytek Europe | | 1996 |
| Hytek Europe | | 1993 |
| I AM ME NOW Ltd | Other services | 2021 |
| I J M Couriers Ltd | Transport & logistics | 2017 |
| I Repair Service Centre Ltd | Wholesale & retail | 2022 |
| I Wall Installations Limited | Extraterritorial | 2003 |
| I Wall Limited | Manufacturing | 1996 |
| I Wanted That Ltd | Wholesale & retail | 2025 |
| I.J. Marketing Services Limited | Professional & scientific | 2011 |
| I3PO Ltd | Professional & scientific | 2013 |
| IAN Chamberlain Groundworks Limited | Construction | 2015 |
| IAN Cockbain Wealth Management Limited | Administrative & support | 2003 |
| Ibbotson Consulting Ltd | Professional & scientific | 2023 |
| Icarus Properties Ltd | Real estate | 2022 |
| IEG Consulting Limited | Professional & scientific | 2019 |
| Igloo Restaurants Ltd | Hospitality | 2018 |
| Ignite People Partners Ltd | Administrative & support | 2026 |
| IM Payments Ltd | Professional & scientific | 2021 |
| Immersion Events Ltd | Hospitality | 2025 |
| Imparta Consulting Ltd | Information & communication | 2003 |
| Imperium People Ltd | Administrative & support | 2021 |
| IN Cool Company Ltd | Education | 2021 |
| IN Event Management Limited | Administrative & support | 2025 |
| IN London Limited | Other services | 2006 |
| IN This Together Cards Ltd | Wholesale & retail | 2022 |
| IN3DINSIGHTS Ltd | Professional & scientific | 2022 |
| Indesosa Limited | Administrative & support | 2010 |
| India by Florence Ltd | Wholesale & retail | 2024 |
| Infinigate Global Services Limited | Wholesale & retail | 1999 |
| Information Facilities Management Limited | Information & communication | 2000 |