| Hawthorne Advisory Ltd | Professional & scientific | 2026 |
| Haydon School | Education | 2011 |
| Hayleys Limited | Information & communication | 1998 |
| Hayward's Mowing Limited | Agriculture & fishing | 2004 |
| Hazel Homes for Autism Ltd | Health & social care | 2017 |
| HB Orthopaedics Ltd | Health & social care | 2013 |
| Hbandali Associates Limited | Health & social care | 2021 |
| HBS Finance Limited | Professional & scientific | 2004 |
| HC Access Limited | Households | 2024 |
| Hccs Cleaning Services Limited | Construction | 2021 |
| HCM Plastic Surgery Ltd | Health & social care | 2025 |
| HD Employment Law Ltd | Administrative & support | 2026 |
| HD Structures Ltd | Construction | 2020 |
| Hdev Consultancy Ltd | Health & social care | 2026 |
| HDH Properties Ltd | Real estate | 2021 |
| HDN Developments LLP | | 2014 |
| Head, Heart and Soul Ltd | Education | 2007 |
| Headbaker Limited | Information & communication | 2012 |
| Heal Angels Limited | Administrative & support | 2019 |
| Heal Health Limited | Extraterritorial | 2022 |
| Heal Tone Ltd | Wholesale & retail | 2023 |
| Healixer Group Limited | Wholesale & retail | 2026 |
| Health Empowerment Collective (HEC) CIC | Other services | 2026 |
| Health Hive Wellness Ltd | Health & social care | 2025 |
| Health RAJ Ltd | Professional & scientific | 2022 |
| Healthstars Limited | Professional & scientific | 2020 |
| Healthvue Limited | Wholesale & retail | 2009 |
| Healthy Grillz Limited | Extraterritorial | 2018 |
| Heanor Store Ltd | Wholesale & retail | 2026 |
| Heapwell Superfoods Ltd | Wholesale & retail | 2015 |
| Heather's Hounds Walking Ltd | Transport & logistics | 2021 |
| Heathfield Terrace Ltd | Households | 2020 |
| HEATHROW4X4 Ltd | Wholesale & retail | 2020 |
| Heatplumb Ltd | Construction | 2012 |
| HEC Airport Transfer Ltd | Transport & logistics | 2018 |
| Hecate Technologies Limited | Information & communication | 2018 |
| Hector's Fine Wine Limited | Wholesale & retail | 2021 |
| Hedge Advisors Ltd | Financial services | 1992 |
| Heliconia Consulting Ltd | Professional & scientific | 2013 |
| Helios Open Innovation Ventures Holdings Ltd | Financial services | 2022 |
| Helios Open Innovation Ventures Ltd | Professional & scientific | 2022 |
| Hello at LEND365 Ltd | Administrative & support | 2019 |
| Hemington Gate (Friern Barnet) Management Limited | Households | 2013 |
| Hemi’S Daily Meal Ltd | Hospitality | 2022 |
| HEN Holdings Ltd | Financial services | 2025 |
| HER Fitness Limited | Arts & recreation | 2022 |
| Herbal Tea Company Limited | Wholesale & retail | 2021 |
| Herzech Ltd | Health & social care | 2022 |
| Hess Group Limited | Financial services | 2024 |
| Hesthetic Life Ltd | Wholesale & retail | 2025 |
| Hewins Consulting Ltd | Professional & scientific | 2015 |
| Hexmark Records Limited | Information & communication | 2017 |
| Heybridge Dental Ltd | Health & social care | 2021 |
| Heymee Ltd | Information & communication | 2025 |
| Heywood Heating Limited | Construction | 2007 |
| HGS Football Academy Limited | Arts & recreation | 2022 |
| HH Emporium Ltd | Wholesale & retail | 2000 |
| HH Periodontics Ltd | Health & social care | 2023 |
| Hhsd Limited | Information & communication | 2018 |
| Hi-Drylining Ltd | Construction | 2023 |
| Hi-Tech I&E Europe Limited | Professional & scientific | 2006 |
| Hibiscus Homes Ltd | Real estate | 2013 |
| Hibiscus Property Maintenance Limited | Construction | 2017 |
| Hibond Group Limited | Wholesale & retail | 2025 |
| Hidden Mango Ltd | Information & communication | 2025 |
| Higgs Flavour Project Limited | Hospitality | 2020 |
| High Level Electrics Ltd | Construction | 2013 |
| High Peak Pictures Limited | Professional & scientific | 2022 |
| High Spirits Trading Ltd | Wholesale & retail | 2023 |
| Highcross Capital Ltd | Professional & scientific | 2023 |
| Highcross Commercial Ltd | Financial services | 2021 |
| Highcross Financial Ltd | Financial services | 2020 |
| Highridge Capital Limited | Real estate | 2024 |
| Hiimm Limited | Hospitality | 2025 |
| Hike Pyrenees Ltd | Administrative & support | 2007 |
| Hill Wooldridge & Co. Ltd. | Professional & scientific | 1998 |
| Hillcrest Realty Ltd | Real estate | 2013 |
| Hillside Radlett Management Ltd | Households | 2021 |
| Hillspar Estates Limited | Real estate | 1983 |
| Hillview Project Services Ltd | Construction | 2018 |
| Hillview Solutions Limited | Information & communication | 2015 |
| Himani & Co Ltd | Real estate | 2025 |
| Hind (UK) Limited | Real estate | 1999 |
| Hiraki Investments Ltd | Real estate | 2015 |
| Hired Place Business Solutions Limited | Administrative & support | 2014 |
| Hiren Patel Solicitors Limited | Professional & scientific | 2018 |
| Hitea Pinner Ltd | Hospitality | 2024 |
| Hiten Manglani Limited | Professional & scientific | 2012 |
| Hjey Solutions Limited | Wholesale & retail | 2024 |
| HJS Investments Limited | Real estate | 2008 |
| Hkfoodhouse Ltd | Hospitality | 2023 |
| HKM Projects Limited | Information & communication | 2024 |
| Hknp Properties Limited | Real estate | 2021 |
| HKS Derm Limited | Health & social care | 2021 |
| HKS Firm Ltd | Real estate | 2024 |
| HL Holdco Limited | Financial services | 2016 |
| HMA Transportations Ltd | Transport & logistics | 2024 |
| Hmam Holdings Limited | Financial services | 2026 |
| HN Generics Ltd | Manufacturing | 2025 |
| HNK Ltd | Wholesale & retail | 2020 |