| Hardley Printing Company Limited | Real estate | 1964 |
| Hardwick Specsavers Limited | Wholesale & retail | 2016 |
| Harehound Services Ltd | Information & communication | 2025 |
| Harlesden Specsavers Limited | Wholesale & retail | 2008 |
| Harlesden Visionplus Limited | Wholesale & retail | 2008 |
| Harlow Specsavers Hearcare Limited | Wholesale & retail | 2018 |
| Harlow Specsavers Limited | Wholesale & retail | 1993 |
| Harlow Visionplus Limited | Wholesale & retail | 1993 |
| Harmful Traditional Practices Training and Consultancy Ltd | Professional & scientific | 2025 |
| Harmsworth Homes Limited | Real estate | 2014 |
| Harness Consulting Ltd | Professional & scientific | 2011 |
| Harp Software Limited | Information & communication | 1997 |
| Harp Visual Communications Limited | Manufacturing | 1998 |
| Harpenden Specsavers Limited | Wholesale & retail | 2022 |
| Harpers Weybridge Limited | Construction | 2009 |
| Harpurhey Specsavers Limited | Wholesale & retail | 2004 |
| Harpurhey Visionplus Limited | Wholesale & retail | 2004 |
| Harringay Specsavers Limited | Wholesale & retail | 2019 |
| Harris Bespoke Ltd | Wholesale & retail | 2016 |
| Harris Homes Kitchens & Carpentry Ltd. | Construction | 2020 |
| Harris Interior Solutions Limited | Extraterritorial | 2016 |
| Harrison Technology Limited | Information & communication | 2008 |
| Harrod Tailored Estates Ltd | Real estate | 2022 |
| Harrogate Specsavers Hearcare Limited | Wholesale & retail | 2006 |
| Harrogate Specsavers Limited | Wholesale & retail | 1991 |
| Harrogate Visionplus Limited | Wholesale & retail | 2001 |
| Harrop Installations Limited | Construction | 2021 |
| Harrop Properties Ltd | Real estate | 2018 |
| Harropeak Projects Ltd | Administrative & support | 2024 |
| Harrow Specsavers Hearcare Limited | Wholesale & retail | 2006 |
| Harry Spake Lettings Limited | Hospitality | 2019 |
| Harry-Flatters Ltd | Professional & scientific | 2014 |
| Hart Charity Nominees Limited | Administrative & support | 1976 |
| Hart Charity Trust Company Limited | Administrative & support | 1976 |
| Hartlepool Specsavers Hearcare Limited | Wholesale & retail | 2018 |
| Hartlepool Specsavers Limited | Wholesale & retail | 1993 |
| Hartlepool Visionplus Limited | Wholesale & retail | 1993 |
| Harvester Court (Catisfield) Limited | Households | 1995 |
| Harvey Interpreting Limited | Professional & scientific | 2019 |
| Harwill Consultancy Ltd | Professional & scientific | 2023 |
| Hashtag Social Ltd | Information & communication | 2021 |
| Haskabadayi Ltd | Hospitality | 2016 |
| Hastings Sedlescombe Road Specsavers Limited | Wholesale & retail | 2018 |
| Hastings Specsavers Hearcare Limited | Wholesale & retail | 2006 |
| Hastings Specsavers Limited | Wholesale & retail | 2003 |
| Hastings Visionplus Limited | Wholesale & retail | 2003 |
| Hastrec Ltd | Administrative & support | 2020 |
| Hatton Carpentry Ltd | Construction | 2020 |
| Havant Specsavers Hearcare Limited | Wholesale & retail | 2003 |
| Haven Enterprises Limited | Real estate | 2025 |
| Haven Manor Management Company Limited | Real estate | 2006 |
| Haven Rose Residential Care Home Ltd | Health & social care | 2008 |
| Haverfordwest Specsavers Limited | Wholesale & retail | 1991 |
| Haverhill Specsavers Limited | Wholesale & retail | 2003 |
| Hawkins Financial Limited | Financial services | 2014 |
| Hawksworth Design Limited | Construction | 2002 |
| Hawthorn Financial Services (Wealth Management) Limited | Financial services | 2015 |
| Hawthorn Properties (UK) Limited | Real estate | 1993 |
| Hayden Construction Services Limited | Construction | 2007 |
| Hayes and Associates Limited | Financial services | 2023 |
| Hayes Flooring Contractors Limited | Construction | 2024 |
| Hayes Lombardy Specsavers Limited | Wholesale & retail | 2018 |
| Hayes Plumbing and Heating Ltd | Construction | 2021 |
| Hayes Specsavers Limited | Wholesale & retail | 2004 |
| Hayes Visionplus Limited | Wholesale & retail | 2004 |
| Hayley Hays Luxe Boutique Ltd | Wholesale & retail | 2026 |
| Hayley Renouf Art Services Ltd | Education | 2022 |
| Hayling Estates Ltd | Real estate | 2025 |
| Haywards Heath Specsavers Hearcare Limited | Wholesale & retail | 2011 |
| Haywards Heath Specsavers Limited | Wholesale & retail | 2005 |
| Haywards Heath Visionplus Limited | Wholesale & retail | 2005 |
| Hazardous Area Remediation Limited | Water & waste | 2023 |
| Hazelbrook Consulting Ltd | Professional & scientific | 2024 |
| Hazleton Garage Services Ltd. | Wholesale & retail | 2011 |
| HB Executive-Airport-Travel Ltd | Transport & logistics | 2023 |
| HB Holistics & Coaching Ltd | Professional & scientific | 2022 |
| HB Villages Developments (Crewe) Ltd | Real estate | 2020 |
| HBN Lettings Ltd | Real estate | 2020 |
| HBQ Limited | Hospitality | 2024 |
| HBS Solar Investments Ltd | Construction | 2015 |
| HBX Sales Limited | Administrative & support | 2013 |
| HC 1344 Limited | Administrative & support | 2023 |
| HC Support Services Limited | Administrative & support | 2004 |
| HC Technology Ltd | Information & communication | 2015 |
| Hccs Partners Ltd | Wholesale & retail | 2025 |
| Hcrd Limited | Real estate | 2011 |
| HE Jewellers Limited | Wholesale & retail | 2025 |
| Head Squared Aquatics Limited | Administrative & support | 2006 |
| Head Squared Holdings Limited | Administrative & support | 2006 |
| Headingley Specsavers Limited | Wholesale & retail | 2012 |
| Headz-Uk Ltd | Other services | 2022 |
| Healey Developments Southern Ltd | Construction | 2025 |
| Healing Hands Healthcare Services Ltd | Health & social care | 2025 |
| Health and Social Care Services Ltd | Health & social care | 2015 |
| Healthcare in Mind Limited | Health & social care | 2024 |
| Healthy Relationships Awareness Centre CIC | Health & social care | 2025 |
| Heat a Floor Design Ltd | Professional & scientific | 2018 |
| Heat Engineering Solutions Limited | Construction | 2026 |
| Heat Pump Biker Limited | Construction | 2026 |
| Heatec Services Limited | Construction | 2002 |