| Hara ID Ltd | Professional & scientific | 2025 |
| Harcourt Stirling Solicitors Ltd | Professional & scientific | 2020 |
| Hare Raising Productions Ltd | Information & communication | 2012 |
| Harji's India Ltd | Administrative & support | 2019 |
| Harker IT Training Services Ltd | Information & communication | 2019 |
| Harmonyessentials Ltd | Wholesale & retail | 2019 |
| Harper Homes (UK) Ltd | Construction | 2014 |
| Harper Kitchens Ltd. | Wholesale & retail | 2014 |
| Harrops Trading Limited | Real estate | 2018 |
| Hartglobe Limited | Information & communication | 1988 |
| Harvey Construction Limited | Real estate | 1996 |
| Hasthcult Ltd | Wholesale & retail | 2023 |
| Hatch END Properties Limited | Real estate | 1995 |
| Hathiwala Consulting Limited | Information & communication | 2010 |
| Haughton Commercial Ltd | Professional & scientific | 2026 |
| Haughton Holdings Ltd | Financial services | 2026 |
| Hauser Limited | Professional & scientific | 2015 |
| Hausit Limited | Real estate | 2020 |
| Havida Kithcen Ltd | Wholesale & retail | 2026 |
| Haxashield IT & Cyber Solutions Ltd. | Information & communication | 2024 |
| Hazel’S Mental Health Coaching Hub Ltd | Health & social care | 2026 |
| Hbrs Holdings Limited | Financial services | 2026 |
| HCT Properties Limited | Construction | 2002 |
| HD Homes & Property Ltd | Real estate | 2021 |
| Health and Safety Training Consultants Limited | Administrative & support | 2018 |
| Healthy Grill Ltd | Hospitality | 2025 |
| Heartspire Ltd | Health & social care | 2025 |
| Heatvault Ventures Ltd | Wholesale & retail | 2026 |
| Heavenly Olives Ltd | Wholesale & retail | 2025 |
| Helios Ingredients Limited | Wholesale & retail | 2006 |
| Hello Flow London Ltd | Health & social care | 2024 |
| Hello London Investments Limited | Real estate | 2024 |
| Hello Services Ltd | Construction | 2019 |
| Hellowood Carpentry & Joinery Ltd | Construction | 2021 |
| Hemel Solar Limited | Construction | 2022 |
| Hendox Ltd | Professional & scientific | 2022 |
| Henry Street Investments Limited | Professional & scientific | 2022 |
| Hepcom Limited | Information & communication | 2014 |
| Hera Fashion Ltd | Other services | 2025 |
| Herbal Life Ltd | Health & social care | 2018 |
| Heritage Outcomes Ltd | Professional & scientific | 2019 |
| Heritage Restoration 1 Ltd | Manufacturing | 2018 |
| Hero Transformation Limited | Information & communication | 2016 |
| Heron Court Management Limited | Real estate | 1975 |
| Hesed Learning and Development Limited | Education | 2020 |
| Heston Football Club Limited | Arts & recreation | 2022 |
| Heston in the Community CIC | Education | 2023 |
| Hexagon Homes Global Limited | Real estate | 2026 |
| Hexanta Limited | Information & communication | 2025 |
| HEY Structure Limited | Professional & scientific | 2025 |
| HG Fivey Store Ltd | Wholesale & retail | 2023 |
| HIA Music Limited | Wholesale & retail | 2016 |
| Hidden Energy Ltd | Professional & scientific | 2026 |
| High & DRY Beer Co Ltd | Manufacturing | 2025 |
| High Performance and Fulfillment Ltd | Wholesale & retail | 2019 |
| High Resolution AV Ltd | Information & communication | 2020 |
| Highlightdynamics Ltd | Professional & scientific | 2019 |
| Highv Consulting Limited | Information & communication | 2020 |
| Hill House Antiques & Decorative Arts Limited | Wholesale & retail | 2018 |
| Hilltop ADS Ltd | Information & communication | 2014 |
| HIP Hops Cards Ltd | Manufacturing | 2015 |
| Historic Steam Limited | Arts & recreation | 1974 |
| Hkav Ltd | Information & communication | 2019 |
| HKB Design & Build Ltd | Professional & scientific | 2014 |
| Hkklaw Limited | Professional & scientific | 2019 |
| HKS Engineering Consultancy Limited | Professional & scientific | 2021 |
| Hmelitebuildingsolutions Limited | Construction | 2025 |
| Hoam Build Ltd | Construction | 2020 |
| Hoaxstudio Ltd | Information & communication | 2021 |
| Hobasisu Trading Limited | Wholesale & retail | 2018 |
| Hofseth Biocare UK Ltd | Wholesale & retail | 2023 |
| Holicas Limited | Administrative & support | 2024 |
| HOLIDAYS2CHERISH Ltd | Administrative & support | 2025 |
| Holistic Pharmacist Ltd | Wholesale & retail | 2022 |
| Homeroost Limited | Professional & scientific | 2002 |
| Honest Build & Refurb Ltd | Construction | 2026 |
| Honey Monster Foods Limited | Manufacturing | 2006 |
| Horizon Engineering Associates Limited | Construction | 2014 |
| Hospitality Digital Hub Limited | Other services | 2018 |
| Hoti Horizon Ltd | Wholesale & retail | 2026 |
| Hotspur Helium Jordan Limited | Manufacturing | 2025 |
| Hotspur Helium Limited | Manufacturing | 2024 |
| House of Flying Stitches Ltd | Manufacturing | 2023 |
| House Repair London Ltd | Construction | 2025 |
| Hout Food Ltd | Hospitality | 2025 |
| HRH Homes Limited | Construction | 2007 |
| Hristov Property Investment Limited | Water & waste | 2023 |
| HRW Property Limited | Real estate | 2017 |
| Hsmr Consulting Limited | Information & communication | 2021 |
| HT Medical & Rescue Ltd | Health & social care | 2025 |
| Huetech Solutions Ltd | Information & communication | 2023 |
| Hugh Dickinson Consultancy Services Limited | Professional & scientific | 2019 |
| Human UP Ltd | Wholesale & retail | 2025 |
| Humitechbiosmart London Ltd | Other services | 2017 |
| Hundred Horses Ltd | Professional & scientific | 2024 |
| Hunters MAIN11 Limited | Real estate | 2026 |
| HUX Digital Ltd | Professional & scientific | 2019 |
| HVW Belvedere Limited | Hospitality | 2026 |
| Hybrid Civils Ltd | Construction | 2024 |
| Hybrid Plant Hire Ltd | Administrative & support | 2019 |