| Home Extension Team Holdings Limited | Financial services | 2003 |
| Home Interior Design Limited | Construction | 2009 |
| Home-School Tutoring North & West London Limited | Education | 2025 |
| Homecore Services Limited | Construction | 2023 |
| Homes and Lettings Limited | Real estate | 2017 |
| Homessence Limited | Real estate | 2004 |
| Honey Bunch LDN Flowers Ltd | Wholesale & retail | 2020 |
| Honey Tree Surgeons Limited | Agriculture & fishing | 2014 |
| HOO Park Restoration Limited | Real estate | 1998 |
| Hoopers Logistics Ltd | Transport & logistics | 2021 |
| Hope Spiritual Centre Limited | Hospitality | 2022 |
| Hopscotch and Conkers Ltd | Wholesale & retail | 2011 |
| Horizon PUB Company Limited | Hospitality | 2019 |
| Horizon Technology Consulting Ltd | Information & communication | 2024 |
| Horizons Edge Construction and Project Management Ltd | Construction | 2025 |
| Horley Bookshops Limited | Manufacturing | 1999 |
| Horne Rigging Limited | Construction | 2018 |
| Hospital Way Management Ltd | Real estate | 2023 |
| Hoss Lighting Limited | Information & communication | 2023 |
| Hot Squash Limited | Manufacturing | 2010 |
| Hot WOK Chinese Kitchen Ltd | Hospitality | 2025 |
| Hotlisted Network Limited | Information & communication | 2000 |
| Houghton Architecture Ltd | Professional & scientific | 2021 |
| Houghton Builders Ltd | Construction | 2024 |
| Houghton Paper Consultants Limited | Professional & scientific | 2023 |
| Hound Marketing Limited | Professional & scientific | 2020 |
| House Creative Design Limited | Professional & scientific | 2016 |
| House Creative Print Limited | Professional & scientific | 2016 |
| House Host Limited | Real estate | 2024 |
| House Marketing Group Limited | Real estate | 2017 |
| House Marketing Media Ltd | Professional & scientific | 2026 |
| House of Fitness Ltd | Arts & recreation | 2019 |
| House of Holley Ltd | Professional & scientific | 2019 |
| House of Legal Ltd | Professional & scientific | 2019 |
| House Water Limited | Wholesale & retail | 2008 |
| House Water Trade Mark Limited | Professional & scientific | 2008 |
| Hove-The Sequel Limited | Construction | 2023 |
| HOW and WHY Ltd | Extraterritorial | 2020 |
| HOW Farming Limited | Agriculture & fishing | 2016 |
| Howard Court (Letchworth) Residents Association Limited | Real estate | 1965 |
| HPT (Luton) Limited | Professional & scientific | 2004 |
| HR Circle UK Limited | Professional & scientific | 2011 |
| HRH Holmes & SON Limited | Wholesale & retail | 2004 |
| HS Techremedy LP | | 2021 |
| HSM Design and Build Ltd | Administrative & support | 2020 |
| Htfc (Top Field) Ltd | Arts & recreation | 1991 |
| HTH Finance Limited | Financial services | 2016 |
| Hub Fit Ltd | Arts & recreation | 2023 |
| Hudson-Glynn Consulting Ltd | Professional & scientific | 2023 |
| Hugh & Melanie Eaglesham Property Limited | Real estate | 2024 |
| Hughes Crescent Ltd | Financial services | 2025 |
| Hughes Holdings & Consultancy Limited | Information & communication | 2023 |
| Huixue British Guardianship Ltd | Education | 2025 |
| Hull Property Group Ltd. | Construction | 2025 |
| Huma Medical Limited | Health & social care | 2014 |
| Humanitas Charity | Health & social care | 2006 |
| Humble Arnold Associates Limited | Extraterritorial | 2025 |
| Humidity Control UK Ltd | Other services | 2023 |
| Hunt Commerce Ltd | Wholesale & retail | 2026 |
| Hunter Shore Group Limited | Administrative & support | 2023 |
| Huskies Limited | Professional & scientific | 2023 |
| Hustl Hitchin Ltd | Arts & recreation | 2025 |
| HVS ST Ibbs Limited | Professional & scientific | 2018 |
| HVS ST Ibbs Trustee Limited | Administrative & support | 2023 |
| HW Associates LLP | | 2003 |
| Hyde Motor Group Limited | Wholesale & retail | 2022 |
| Hydra Contracts Ltd | Administrative & support | 2019 |
| Hydras Property Limited | Real estate | 2024 |
| Hydrocomm Limited | Professional & scientific | 2007 |
| Hyena Bees Consultancy Services Ltd | Professional & scientific | 2022 |
| Hyper Mode Ltd | Information & communication | 2020 |
| I J M Bars Limited | Hospitality | 2018 |
| I Sell N Buy IT Ltd | Wholesale & retail | 2022 |
| I Want Storage Limited | Real estate | 2021 |
| I.P.E Sheet Metal Ltd | Manufacturing | 2019 |
| I.P.E Systems Ltd | Manufacturing | 2019 |
| I.S.A. Coaching Limited | Arts & recreation | 2009 |
| IAN C Crisp (Plant Hire) Limited | Real estate | 1957 |
| IAN Cooper Holdings Limited | Administrative & support | 2020 |
| IAN Murton Hypnotherapy Limited | Health & social care | 2025 |
| IAN Summerbee Limited | Construction | 2003 |
| IB Aviation Ltd | Professional & scientific | 2013 |
| IBD Licensing Limited | Extraterritorial | 2011 |
| Ibex Communications Limited | Information & communication | 2013 |
| Ibts Imports Limited | Wholesale & retail | 2025 |
| IC VIP Interiors Limited | Professional & scientific | 2013 |
| Icfm Consult Ltd | Professional & scientific | 2025 |
| ICT Connections (Rebelo) Limited | Education | 2007 |
| Ideal Maintenance Solutions Ltd | Administrative & support | 2014 |
| Ideasanvil Ltd | Information & communication | 2000 |
| Igenomics Limited | Professional & scientific | 2025 |
| Iglow Limited | Professional & scientific | 2014 |
| IGR Consultancy Ltd | Professional & scientific | 2024 |
| IHC Management Ltd | Professional & scientific | 2025 |
| IHS Structural Engineering Ltd | Professional & scientific | 2018 |
| Ikherma Consulting Ltd | Professional & scientific | 2022 |
| Ilink Educators Ltd | Education | 2023 |
| Illuminate Medical Ltd | Professional & scientific | 2016 |
| Ilsley Finance Limited | Financial services | 2002 |
| Imaginarium Future Limited | Professional & scientific | 2021 |