| Harrar Limited | Professional & scientific | 2013 |
| Harrem Jewellery Ltd | Wholesale & retail | 2021 |
| Harrik Publishing and Productions Ltd | Information & communication | 2024 |
| Harrington Property Group Ltd | Real estate | 2020 |
| Harringtons of Fulham Limited | Wholesale & retail | 2003 |
| Harris Carpentry Contractors Limited | Construction | 2014 |
| Harris Property Investment Portfolio Limited | Professional & scientific | 2021 |
| Harrison (London) Limited | Construction | 1996 |
| Harrison James Financial Planners Limited | Financial services | 2009 |
| Harrisons Jewellers Limited | Wholesale & retail | 2007 |
| Harrogate Groundworks Solutions Ltd | Construction | 2022 |
| Harry Logistics Ltd | Transport & logistics | 2014 |
| Harry Utilities Ltd | Construction | 2020 |
| Harsun Holdings Limited | Financial services | 2025 |
| Hart's Food & Events Ltd | Hospitality | 2012 |
| Hartdean Limited | Wholesale & retail | 1997 |
| Hartgrange Limited | Other services | 1988 |
| Hartland Properties Ltd | Real estate | 2019 |
| Hartley Consulting - FE Solutions Limited | Professional & scientific | 2026 |
| Hartwell Oaks Limited | Administrative & support | 2024 |
| Harue Limited | Other services | 2022 |
| Harven IT Services Limited | Information & communication | 2010 |
| Harvey Diack Creative Services Ltd | Information & communication | 2024 |
| Harvey Spackfield Renewables Limited | Wholesale & retail | 2025 |
| Harvi Infotech Limited | Information & communication | 2026 |
| Harvington Co. Ltd | Wholesale & retail | 2025 |
| Harvon Limited | Construction | 2000 |
| Harwinoz Ltd | Financial services | 2024 |
| Harzia Limited | Professional & scientific | 2015 |
| HAS Impact Ltd | Information & communication | 2023 |
| Hasanconstructiongroup Limited | Construction | 2025 |
| Hashi Services Limited | Transport & logistics | 2026 |
| Hashim Makera Ltd | Transport & logistics | 2026 |
| Hashtag 2 Go Ltd | Hospitality | 2020 |
| Hashtag Mechanic Limited | Wholesale & retail | 2014 |
| Hashtagg Group Limited | Administrative & support | 2024 |
| Hass Auto Detailing Limited | Administrative & support | 2025 |
| Hassan Shahzad Ltd | Education | 2025 |
| Hassons (UK) Ltd | Wholesale & retail | 2012 |
| Hassons Sports Ltd | Wholesale & retail | 2015 |
| Hastens Beds UK Limited | Wholesale & retail | 2010 |
| Hastings Bath House Ltd | Real estate | 2025 |
| Hastings Contemporary | Other services | 2012 |
| Hastovan Developments Limited | Construction | 2020 |
| Hastovan Operations Limited | Real estate | 2022 |
| Hatah Ltd | Wholesale & retail | 2024 |
| Hatbox Developments Ltd | Construction | 2023 |
| Hatchet Harry's Ltd | Arts & recreation | 2019 |
| Hatfield Boodle Ltd | Construction | 2016 |
| Hatt Properties Limited | Construction | 2024 |
| Hattie Newman Limited | Administrative & support | 2017 |
| Hatton IT Services Ltd | Information & communication | 2022 |
| Hatton Solutions Limited | Construction | 2019 |
| Hatuahub Ltd | Professional & scientific | 2025 |
| Haus Investment Group Ltd | Construction | 2026 |
| Haus of Carbon Limited | Manufacturing | 2026 |
| Haus Prop Ltd | Real estate | 2023 |
| Hausaa Properties Ltd | Real estate | 2023 |
| Haut DE Gamme Ltd | Hospitality | 2013 |
| HAV Properties Ltd | Real estate | 2019 |
| Have a Nice Day Limited | Real estate | 2017 |
| Haven Expressions Ltd | Other services | 2018 |
| Haven Housing Developments Limited | Construction | 1994 |
| Haven Interactive CIC | Education | 2026 |
| Haven Key Healthcare Ltd | Health & social care | 2025 |
| Haven Key Homes Ltd | Real estate | 2024 |
| Havenlymarket Digital Technology Ltd. | Wholesale & retail | 2025 |
| Havenwise Management Limited | Real estate | 2025 |
| Haversham Management Limited | Administrative & support | 2002 |
| Haversham Sailing Club Limited | Hospitality | 1991 |
| Havilah Assets Holding Ltd | Real estate | 2017 |
| Havilah Care Ltd | Health & social care | 2017 |
| Havilah Springs C.I.C. | Real estate | 2021 |
| Havise Globol Limited | Real estate | 2026 |
| Havom Technologies Ltd | Information & communication | 2025 |
| Hawk Energy & Electrical Supplies Ltd | Construction | 2024 |
| Hawk EYE Financial Consultants Ltd | Financial services | 2013 |
| Hawk Projects Ltd | Construction | 2021 |
| Hawkes Bell Ltd | Administrative & support | 2023 |
| Hawkhurst Accounting Limited | Professional & scientific | 2024 |
| Hawksmeadow Limited | Construction | 2003 |
| Hawksmoor Bespoke Ltd | Construction | 2026 |
| Hawksmoor Construction London Ltd | Construction | 2026 |
| Hawksmoor Developments Ltd | Real estate | 2018 |
| Hawkswell Land Limited | Construction | 1958 |
| Hawthorne Digital Consulting Limited | Information & communication | 2026 |
| HAY Life Ltd | Wholesale & retail | 2023 |
| Hay-Money Ltd | Information & communication | 2026 |
| Hay-Tech Precision Engineering Limited | Manufacturing | 2010 |
| Hayat Sports Limited | Manufacturing | 2009 |
| Haycocks Cottage Limited | Hospitality | 2021 |
| Haycroft (Cosgrove) Ltd | Hospitality | 2014 |
| Hayden Hair Studio Ltd | Other services | 2021 |
| Haydock Commercial Vehicles Limited | Wholesale & retail | 1984 |
| Hayer Realty Ltd | Real estate | 2024 |
| Hayes AM Investments Limited | Professional & scientific | 2025 |
| Hayleyjames Services Limited | Health & social care | 2017 |
| Haypp Limited | Wholesale & retail | 2022 |
| Haytay Property Solutions Ltd | Construction | 2023 |
| Haythorn Property Limited | Real estate | 2003 |