| Hillier Project Management Ltd | Professional & scientific | 2017 |
| HIX IT Ltd | Other services | 2021 |
| HJ Robertson Ltd | Manufacturing | 2021 |
| HOB Farms Limited | Administrative & support | 2012 |
| Holistic Housekeeping Ltd | Administrative & support | 2015 |
| Holloway Properties Limited | Real estate | 1989 |
| Hollowsplit Ltd | Wholesale & retail | 2019 |
| Hollyoaks Holdings Ltd | Financial services | 2021 |
| Holmeleys Consulting Ltd | Information & communication | 2015 |
| Holmer Ltd | Administrative & support | 2022 |
| Home Farm Nurseries (Pinvin) Limited | Agriculture & fishing | 1979 |
| Homestyle Property Solutions Ltd | Construction | 2025 |
| Honeycomb Sky Limited | Information & communication | 2017 |
| HOO Lodge Holdings Ltd | Real estate | 2016 |
| Hooley Time Limited | Hospitality | 2008 |
| Hooper & Co Building Limited | Construction | 2024 |
| Hooper & Co Holdings Ltd | Financial services | 2025 |
| Hoptraffic Ltd | Wholesale & retail | 2019 |
| Hot Tottie Sunbeds Limited | Other services | 2025 |
| Hot Tottie Tanning Limited | Other services | 2023 |
| Hotchpotch Organics Ltd | Agriculture & fishing | 2021 |
| Houghton Brickwork Limited | Construction | 2020 |
| Hourtime Limited | Financial services | 1988 |
| HS Morrison Ltd | Administrative & support | 2021 |
| Hughes & Sons Limited | Extraterritorial | 2001 |
| Hunter and Badger Ltd | Wholesale & retail | 2024 |
| HWE Imaging Limited | Health & social care | 2024 |
| Hygienic Cleaning Company (UK) Ltd | Water & waste | 1965 |
| I SEE Solutions Limited | Professional & scientific | 2012 |
| Icke Partners Limited | Agriculture & fishing | 2018 |
| Iconic Lifestyle and Well Being Ltd | Other services | 2022 |
| ID Tanner Ltd | Health & social care | 2022 |
| ID2 Business Image Design Ltd | Professional & scientific | 2007 |
| Iden Green Ltd | Administrative & support | 2022 |
| Idole Ltd | Transport & logistics | 2022 |
| Ilex Legal Ltd | Professional & scientific | 2022 |
| Iliave Ltd | Administrative & support | 2022 |
| Ilton Ltd | Transport & logistics | 2022 |
| Immobility Ltd | Administrative & support | 2019 |
| Imperial Breast Surgeon Ltd | Health & social care | 2014 |
| Imperial Marques Ltd | Wholesale & retail | 2018 |
| Impexum Ltd | Wholesale & retail | 2025 |
| Implant Health Limited | Health & social care | 2021 |
| IN the Running Ltd | Arts & recreation | 2021 |
| In-Form Consulting Ltd | Professional & scientific | 2008 |
| Industrial Applications Consultancy Ltd | Professional & scientific | 2023 |
| Industrial Interface Systems Ltd | Manufacturing | 2022 |
| Ingenium Transitioning Ltd | Administrative & support | 2013 |
| Ingles Services Limited | Construction | 2023 |
| INNOV8IVE Software Limited | Arts & recreation | 2009 |
| Innovative Safety Systems Limited | Manufacturing | 2009 |
| Insideout Architecture + Interiors Ltd | Professional & scientific | 2005 |
| Inspired Managers Limited | Professional & scientific | 2008 |
| Intech Industries Ltd | Information & communication | 2006 |
| Integrated Engineering Solutions Ltd | Professional & scientific | 2023 |
| Inverc Ltd | Health & social care | 2019 |
| Inverkeilor Ltd | Transport & logistics | 2021 |
| Invest Tech Consulting Ltd | Professional & scientific | 2016 |
| Invest Tech Ltd | Manufacturing | 2014 |
| IP Transport Limited | Transport & logistics | 2010 |
| Isla Essence Ltd | Wholesale & retail | 2025 |
| ITR UK Holding Ltd | Financial services | 2019 |
| IU Weeks Ltd | Transport & logistics | 2021 |
| IWB Farms Ltd | Agriculture & fishing | 2025 |
| Izalica Ltd | Wholesale & retail | 2019 |
| Izona Limited | Manufacturing | 2021 |
| J & D Properties Midlands Limited | Real estate | 2013 |
| J a Britto Ltd | Health & social care | 2015 |
| J Bayliss Ltd | Construction | 2020 |
| J J T Sports Limited | Arts & recreation | 2002 |
| J R C Carpentry Contractors Ltd | Construction | 2014 |
| J&A Estate Agents Ltd | Real estate | 2014 |
| J.F. Chilman (Farriers) Limited | Manufacturing | 2003 |
| J.K.T. Properties Ltd | Real estate | 2003 |
| J.W. Libell Limited | Professional & scientific | 1962 |
| Jack L Barnett Limited | Professional & scientific | 2014 |
| Jackson Family Funeral Directors Limited | Other services | 2018 |
| Jackson Family Funerals Holdings Limited | Financial services | 2021 |
| Jacksons Funerals Limited | Administrative & support | 2020 |
| Jaffa Support & Consultancy Ltd | Financial services | 2008 |
| Jamie Macleod Wealth Management Ltd | Financial services | 2019 |
| Janus Care Partners Limited | Professional & scientific | 2019 |
| JAP Investments Limited | Real estate | 2021 |
| JC Window Cleaner Ltd | Administrative & support | 2023 |
| JCW Capital Ltd | Financial services | 2024 |
| JCW Capital One Ltd | Construction | 2025 |
| JCW Management | Financial services | 2024 |
| Jdaa Ltd | Professional & scientific | 2023 |
| JDC Solutions Ltd | Professional & scientific | 2011 |
| JDS Supplies(Midlands) Limited | Wholesale & retail | 2013 |
| Jetvise Ltd | Wholesale & retail | 2019 |
| JHS Laser Ltd | Manufacturing | 2022 |
| Jimmy Pickles Limited | Hospitality | 2015 |
| JJJ Arborist and Forestry Services Limited | Agriculture & fishing | 2020 |
| Jkls Medical Services Ltd | Financial services | 2024 |
| JKT Holdings Limited | Financial services | 2008 |
| JKT Property Holdings Limited | Financial services | 2018 |
| JLI Developments Limited | Real estate | 2025 |
| JMA Property Investor Ltd | Financial services | 2022 |
| Jmcr Design Limited | Professional & scientific | 2012 |