| Harbour & Bay Ltd | Wholesale & retail | 2026 |
| Harbour Automation Ltd | Professional & scientific | 2019 |
| Harbour Banks Property Management Ltd | Hospitality | 2025 |
| Harbour Electrical Limited | Construction | 2009 |
| Harbour Enterprises Ltd | Hospitality | 2019 |
| Harbour Equity Release Ltd | Financial services | 2025 |
| Harbour Escapes Limited | Real estate | 2020 |
| Harbour Facilities South Ltd | Administrative & support | 2023 |
| Harbour Financial Solutions Limited | Professional & scientific | 2022 |
| Harbour Haze Management Company Limited | Households | 2014 |
| Harbour Hill Developments Ltd | Construction | 2020 |
| Harbour Hill Studios Ltd | Administrative & support | 2023 |
| Harbour Home Finance Ltd | Financial services | 2026 |
| Harbour Leasing Ltd | Information & communication | 2022 |
| Harbour Rollers Academy Ltd | Arts & recreation | 2024 |
| Harbour Shine Ltd | Administrative & support | 2020 |
| Harbour Side Contractor’S Ltd | Construction | 2024 |
| Harbour Social Work Ltd | Health & social care | 2021 |
| Harbour Tea Company Limited | Wholesale & retail | 2021 |
| Harbour to Hearth Limited | Administrative & support | 2026 |
| Harbour Transport Limited | Transport & logistics | 2009 |
| Harbour VA Ltd | Administrative & support | 2021 |
| Harbour View (Catalina) Management Company Limited | Households | 2014 |
| Harbour View (Poole) Limited | Households | 1962 |
| Harbour View Estates Ltd | Construction | 2022 |
| Harbour View Photography Limited | Professional & scientific | 2022 |
| Harbour Warehousing Ltd | Transport & logistics | 2023 |
| Harbourlight Accounting and Advisory Ltd | Professional & scientific | 2026 |
| Harbourside Connections Ltd | Construction | 2021 |
| Harbourside Developments 2022 Limited | Construction | 2023 |
| Harbourside Distribution Ltd | Wholesale & retail | 2024 |
| Harbourside Financial Trading Ltd | Wholesale & retail | 2022 |
| Harbourside Holdings Limited | Real estate | 2018 |
| Harbourside Homes Ltd | Construction | 2004 |
| Harbourside Homes Property Management Limited | Households | 2017 |
| Harbourside Mansion Limited | Households | 1996 |
| Harbourside Plumbing & Heating Ltd | Construction | 2025 |
| Harbourside Trading Company Limited | Real estate | 1992 |
| Harbourside Whitstone Ltd | Real estate | 2019 |
| Harboursoft Ltd | Professional & scientific | 2018 |
| Harbourstone Accounting Limited | Professional & scientific | 2026 |
| Harbourview Construction Limited | Construction | 2009 |
| Harcourt Kane Investments Ltd | Financial services | 2015 |
| Harcourt Kane Management Ltd | Professional & scientific | 2020 |
| Hardie Properties Limited | Real estate | 2015 |
| Hardie Roofing and Building Limited | Construction | 2002 |
| Hardleys Investment Properties Limited | Construction | 2006 |
| Hardwick Estate Agents Ltd | Real estate | 2024 |
| Hardwick House RTM Company Limited | Households | 2016 |
| Hardy Country Park Limited | Construction | 2023 |
| Hardy Homes Ltd | Real estate | 2014 |
| Hardy Recruitment Ltd | Administrative & support | 2015 |
| Hardy's Building & Maintenance Ltd | Administrative & support | 2017 |
| Harfang Ltd | Professional & scientific | 2023 |
| Hari-Construction Services Ltd | Construction | 2019 |
| Haria Group Ltd | Financial services | 2021 |
| Haripriya Limited | Health & social care | 2023 |
| Harkett Heating & GAS Limited | Construction | 2026 |
| Harkwell Labels Limited | Manufacturing | 2003 |
| Harley Electrical Limited | Construction | 2001 |
| Harley Gardens Management Co. Limited | Extraterritorial | 2015 |
| Harley Sands Ltd | Health & social care | 2022 |
| Harmony by Kate Ltd | Health & social care | 2020 |
| Harmony Land & Developments Ltd | Real estate | 2025 |
| Harnoa Ltd | Real estate | 2021 |
| Harper Beauden Consulting Ltd | Information & communication | 2021 |
| Harper CRC Limited | Health & social care | 2017 |
| Harriet Court (Poole) Management Limited | Households | 2002 |
| Harriet Dormer Consulting Limited | Professional & scientific | 2026 |
| Harris Burgany Limited | Health & social care | 2020 |
| Harris Mortgages Limited | Financial services | 2018 |
| Harrow House International College (Swanage) Ltd | Other services | 1974 |
| Harry Harris Personal Training Ltd | Arts & recreation | 2026 |
| Harry's Group Ltd | Hospitality | 2026 |
| Harry's Snacks Limited | Hospitality | 2002 |
| Hart & Sons (Dorset) Limited | Wholesale & retail | 1974 |
| Hart Residential Property Ltd | Real estate | 2020 |
| Hartech Limited | Professional & scientific | 2017 |
| Hartes Limited | Real estate | 2017 |
| Hartmont JK Limited | Construction | 2024 |
| Hartsofstur Holdings Limited | Professional & scientific | 2008 |
| Haruka Network Limited | Information & communication | 2023 |
| Harvard Ltd | Administrative & support | 2018 |
| Harvey & Harvey Holdings Ltd | Financial services | 2023 |
| Harvey Contracting Ltd | Construction | 2010 |
| Harvey Electrical Limited | Construction | 2009 |
| Harvey Lawson Ltd | Real estate | 2023 |
| Harvey Lodge Management (Guildford) Limited | Households | 1980 |
| Harvey Ventures Limited | Construction | 2019 |
| Harvitta Ltd | Health & social care | 2024 |
| HAS Wings Ltd | Information & communication | 2017 |
| Hasluck Creative Ltd | Other services | 2025 |
| Hastings Home Batteries Limited | Wholesale & retail | 2025 |
| Haswell Healthcare Limited | Extraterritorial | 2018 |
| Hatched Recruitment Group Ltd | Administrative & support | 2024 |
| Hatton Place Management Company Limited | Households | 2004 |
| Hatton Woods Property Management Limited | Real estate | 2018 |
| HAU Saang Limited | Health & social care | 2021 |
| Havana Productions Limited | Professional & scientific | 2018 |
| Haven Financial Solutions Ltd | Financial services | 2017 |