| Hocroft Industrial Limited | Real estate | 2018 |
| Hocroft Properties Limited | Real estate | 2014 |
| Hoffman & Hoffman Ltd | Real estate | 2019 |
| Hoffman Agricultural Ltd | Real estate | 2021 |
| Hoffman Healthcare Corporation Limited | Health & social care | 2017 |
| Holland Park Propco 2 Limited | Real estate | 2024 |
| Hollow Legion Interactive Ltd | Information & communication | 2026 |
| Holly Park London Limited | Real estate | 2026 |
| Holly Park Management Services Ltd | Households | 2022 |
| Holtwhites Ltd | Health & social care | 2015 |
| Home & Quarters Ltd. | Administrative & support | 2015 |
| Home of Hampers by Deepa Ltd | Arts & recreation | 2023 |
| Home Smart Systems Ltd | Construction | 2012 |
| Homebound UK Limited | Real estate | 2005 |
| Homebrands Retail & Wholesale Services Limited | Transport & logistics | 2011 |
| Homeoceutix Ltd | Health & social care | 2026 |
| Homepoint Limited | Real estate | 1999 |
| Homes and Cottages Ltd | Real estate | 2021 |
| Homewood Developments Ltd | Real estate | 2024 |
| Honey Bears Montessori Ltd | Education | 2023 |
| Honeycomb Homes Limited | Real estate | 2013 |
| Honkhonk Limited | Extraterritorial | 2014 |
| Hooked on Events (Management) Limited | Professional & scientific | 2025 |
| Hoot 2820 Limited | Information & communication | 2023 |
| Hope & Grace Create Ltd | Wholesale & retail | 2025 |
| Hoque Optics Ltd | Health & social care | 2014 |
| Horizon Distribution Limited | Wholesale & retail | 2025 |
| Horizons Property Developments Limited | Real estate | 2023 |
| Hormone Harmony Coach Ltd | Professional & scientific | 2026 |
| Hornet Investments Limited | Real estate | 2018 |
| Horseshoe Crescent Northolt Management Limited | Households | 1988 |
| Hospitality Commercial Solutions UK Ltd | Administrative & support | 2025 |
| Hot and Cold Trading Ltd | Arts & recreation | 2024 |
| Hot Plate Buffet Ltd | Hospitality | 2018 |
| Houlihans Public House Limited | Hospitality | 2025 |
| House Land & General Ltd | Real estate | 2007 |
| House Music Limited | Arts & recreation | 1989 |
| House of Eluna Ltd | Wholesale & retail | 2025 |
| House of Guitars Limited | Wholesale & retail | 1982 |
| House of Sakina Limited | Other services | 2025 |
| House of Small Infinities Ltd | Administrative & support | 2025 |
| Housing MIX | Administrative & support | 2020 |
| Howland Court Residents Association (Hatch END) Limited | Households | 1965 |
| HP Optical Limited | Health & social care | 2012 |
| HPJ Holding Limited | Real estate | 2016 |
| HPM Commercial Limited | Construction | 2020 |
| Hptp Limited | Real estate | 2015 |
| HQ ENG Ltd | Construction | 2024 |
| HR and Safety Solution Consultants Ltd | Administrative & support | 2025 |
| HR Business Partners Ltd | Administrative & support | 2011 |
| Hristou Ltd | Professional & scientific | 2014 |
| HRN Investments Limited | Real estate | 2020 |
| HRP Investments Ltd | Real estate | 2015 |
| HS6 Limited | Wholesale & retail | 2025 |
| HSM Accountancy Limited | Professional & scientific | 2011 |
| Hsmc Ventures Limited | Professional & scientific | 2017 |
| HTM Finance Limited | Financial services | 2015 |
| HTS International Enterprises Limited | Real estate | 2020 |
| HU Enterprises Limited | Wholesale & retail | 2017 |
| Hub Architects and Designers Limited | Professional & scientific | 2006 |
| Hudson Thomas Limited | Administrative & support | 2014 |
| Huey & Jude Limited | Real estate | 2025 |
| Humade Global Ltd | Other services | 2025 |
| Humantouch Technologies Ltd | Information & communication | 2020 |
| Hungry Lion Group Limited | Financial services | 2026 |
| Hunt Investments & Development Limited | Real estate | 2025 |
| Hunter and ASH Trading Ltd | Wholesale & retail | 2024 |
| Hunters Lodge Retirement Home Limited | Health & social care | 1985 |
| Hunters SUB Limited | Health & social care | 2021 |
| Huntsmore House Property Management Limited | Households | 1992 |
| Hurdeniz Holding Ltd | Financial services | 2024 |
| Hurlingham Properties Limited | Real estate | 2024 |
| Hurricane Lane Ltd | Real estate | 2002 |
| Husar Ltd | Construction | 2012 |
| Hutchings Accountants Limited | Professional & scientific | 2017 |
| HV Pharma LLP | | 2013 |
| Hvora Consulting Limited | Information & communication | 2025 |
| HWC London Limited | Information & communication | 2014 |
| HWJ Avalon Consulting Limited | Administrative & support | 2026 |
| HX Group Holdings Ltd | Financial services | 2023 |
| Hyfa (UN) Limited | Information & communication | 2024 |
| I & a Prestige Ltd | Real estate | 2025 |
| I Dream Developments Ltd | Construction | 2024 |
| I Point Research Ltd | Professional & scientific | 2012 |
| I&M Garage Ltd | Wholesale & retail | 2021 |
| I-Creatives Limited | Professional & scientific | 2007 |
| I-General Construct Ltd | Construction | 2014 |
| I-Tec Independent Technicians Limited | Health & social care | 2003 |
| I.G.M Interiors Ltd | Construction | 2018 |
| I.I Petcu Carpentry Ltd | Construction | 2011 |
| I.T. Ctrl Limited | Information & communication | 2006 |
| I.W.C. Consulting Ltd | Professional & scientific | 2017 |
| I4XCEL Limited | Professional & scientific | 2015 |
| IA Finance Advisory Ltd | Administrative & support | 2013 |
| IA Training and Coaching Ltd | Professional & scientific | 2004 |
| Iain Gordon Piano Services Limited | Professional & scientific | 2003 |
| IAN Thomson and Company Limited | Professional & scientific | 2003 |
| Ianu Investments Ltd | Real estate | 2021 |
| Ibantek UK Ltd | Professional & scientific | 2021 |
| ICL Holdings Ltd | Financial services | 2021 |