| Hnms Properties Limited | Real estate | 2024 |
| HNP Fitness Limited | Health & social care | 2019 |
| HNZ Properties Ltd | Real estate | 2021 |
| HO Finance Ltd | Administrative & support | 2019 |
| HOC Digital Limited | Administrative & support | 2007 |
| Hocroft Estates Limited | Real estate | 2023 |
| Hocroft Limited | Construction | 2024 |
| Hodson Advocates Limited | Professional & scientific | 2008 |
| Hofa Gallery Limited | Wholesale & retail | 2018 |
| HOG Wild Homes Ltd | Real estate | 2025 |
| Hogwarts Enterprises Ltd | Wholesale & retail | 2023 |
| Holborn Globetrotters Limited | Transport & logistics | 1980 |
| Holdhazel Limited | Construction | 1985 |
| Hollingsworth Mews (Watford) Management Company Limited | Real estate | 2009 |
| Hollybank LLP | | 2016 |
| Hollyroll Ltd | Real estate | 2024 |
| Holo Soft Ltd | Wholesale & retail | 2020 |
| Holosyn Ltd | Health & social care | 2026 |
| Home Brunch Ltd | Hospitality | 2024 |
| Home Carers Ltd | Health & social care | 2022 |
| Home House Properties Limited | Professional & scientific | 2012 |
| Home of Spice Limited | Hospitality | 2019 |
| Home Style Trading Limited | Wholesale & retail | 2024 |
| Home'N'Works Limited | Arts & recreation | 2005 |
| Homemade Spice Ltd | Wholesale & retail | 2025 |
| Homescan Solutions Limited | Wholesale & retail | 2023 |
| Homeworthy Properties Ltd | Real estate | 2024 |
| Honester's Little Media Company Ltd | Professional & scientific | 2016 |
| Honey Honey BEE Limited | Information & communication | 2025 |
| Honey POT Lane Ltd | Wholesale & retail | 2016 |
| Honeypot Auto Centre Limited | Wholesale & retail | 2011 |
| Honeypot Bistro Cafe Ltd | Hospitality | 2024 |
| Honeypot Cosmetics (Wholesale) Limited | Wholesale & retail | 2007 |
| Honeywagon Tankers Limited | Water & waste | 2020 |
| HOP Inns (UK) Limited | Hospitality | 2007 |
| Horan Contractors Limited | Manufacturing | 2016 |
| Horizon PM Ltd | Information & communication | 2015 |
| Horizon Utility Services Ltd | Construction | 2024 |
| Horizons Music Limited | Wholesale & retail | 2020 |
| Horsepower Motor Ltd | Transport & logistics | 2015 |
| Horseshoe Bar Limited | Hospitality | 2007 |
| Horsham Court and Dorking Court Freehold Limited | Households | 2020 |
| Horsham Court RTM Company Limited | Households | 2011 |
| Hoskco Limited | Professional & scientific | 2018 |
| Hotel Booking Agency Limited | Administrative & support | 1994 |
| Hotel Philosophy Limited | Wholesale & retail | 2026 |
| Hotset Limited | Real estate | 1985 |
| House of Arani Ltd | Wholesale & retail | 2025 |
| House of Gujarat Ltd | Education | 2025 |
| House Track Limited | Real estate | 2021 |
| Housing Base C.I.C. | Professional & scientific | 2017 |
| Howton Place Estate Limited | Households | 2020 |
| HPD Properties Limited | Real estate | 2013 |
| HPL Recruitment Ltd | Administrative & support | 2014 |
| HPL Training Ltd | Administrative & support | 2017 |
| Hprotection Services Ltd | Transport & logistics | 2023 |
| HPS (UK) Limited | Construction | 2012 |
| HR & K Investments Ltd | Real estate | 2023 |
| HR Shisha Ltd | Wholesale & retail | 2025 |
| Hrithik Constructions Limited | Real estate | 2026 |
| HRL Infotechs Limited | Information & communication | 2025 |
| HRS Consultants Limited | Professional & scientific | 2008 |
| HS Anaesthetics Limited | Health & social care | 2023 |
| HS Tax Advisers Ltd | Professional & scientific | 2018 |
| HTL Property Limited | Real estate | 2021 |
| Hubiq Holdings Ltd | Professional & scientific | 2024 |
| HUD Productions Ltd | Information & communication | 2024 |
| Hudson Developers Limited | Construction | 2024 |
| Hudson Wright Associates Limited | Professional & scientific | 1993 |
| Huffle Engineering Ltd | Information & communication | 2024 |
| Hugh Lloyd Pharmacy Limited | Wholesale & retail | 2013 |
| Hughes Property Ltd | Real estate | 2017 |
| Human Capital Associates Limited | Administrative & support | 1997 |
| Human Empire Ltd | Wholesale & retail | 2024 |
| Humanicare Limited | Health & social care | 2012 |
| Humans of Branded Content Limited | Information & communication | 2016 |
| Huna London Limited | Manufacturing | 2021 |
| Hunter Environmental Services Limited | Administrative & support | 2013 |
| Hunter Moon Properties Limited | Construction | 2006 |
| Hunter Plant Hire Ltd. | Construction | 2000 |
| Husam Studios Ltd | Professional & scientific | 2020 |
| HV Properties LLP | | 2010 |
| Hybrid Garage Limited | Wholesale & retail | 2020 |
| Hydro Dynamic BBC Ltd | Energy | 2026 |
| Hydrus Property Investments Limited | Real estate | 2021 |
| Hyett Estates Limited | Professional & scientific | 2006 |
| Hyperlynk Ltd | Wholesale & retail | 2024 |
| Hywell Limited | Wholesale & retail | 2011 |
| I & S Electrical, Fire & Security Servces Limited | Construction | 2015 |
| I AM ME Support CIC | Education | 2025 |
| I H Segal & Co Limited | Professional & scientific | 2024 |
| I Think and DO Limited | Information & communication | 2012 |
| I-Care Services CIC | Public administration | 2025 |
| I-Cirrus Limited | Information & communication | 2010 |
| I-Curate Lifestyle Consult Ltd | Professional & scientific | 2015 |
| I-Labs (Europe) Limited | Administrative & support | 2000 |
| I-Serve Group Ltd | Information & communication | 2020 |
| I-Serve Travels Limited | Administrative & support | 2006 |
| I-Ventilation Ltd | Construction | 2019 |
| I.C.E. Medical Solutions Limited | Health & social care | 2015 |