| Griffiths Waste Solutions (GWS) Limited | Water & waste | 2014 |
| Grifflott Engineering Ltd | Manufacturing | 2020 |
| Grimes Industries Ltd | Professional & scientific | 2019 |
| Griot Creative Ltd | Professional & scientific | 2022 |
| Grub Kitchen Limited | Hospitality | 2015 |
| GS Active Limited | Health & social care | 2018 |
| Gsi&C Limited | Professional & scientific | 2023 |
| GSJ Medical Ltd | Wholesale & retail | 2018 |
| GSL Seafood Ltd | Extraterritorial | 2013 |
| GSW Inspection Services Limited | Administrative & support | 2017 |
| Gtech Design and Engineering Limited | Manufacturing | 2018 |
| Gwalia Ecology Ltd | Professional & scientific | 2024 |
| Gwasg Trelodan CYF | Information & communication | 2015 |
| Gwaun Homes Limited | Construction | 2017 |
| GWB Farming Limited | Agriculture & fishing | 2018 |
| Gwernego Homes Limited | Construction | 1987 |
| Gwesty Ventures Ltd | Hospitality | 2021 |
| H B Training Wales Ltd | Education | 2009 |
| H T Installations Limited | Information & communication | 2003 |
| H&K19 Ltd | Hospitality | 2024 |
| Habitat Info Limited | Administrative & support | 2002 |
| Hains & Lewis Limited | Professional & scientific | 2008 |
| Hair Clinical Ltd | Other services | 2019 |
| Hallam Pathology Ltd | Health & social care | 2015 |
| Hamilton Professional Ltd | Financial services | 2026 |
| Hamrun Ltd | Other services | 2022 |
| Hanakant Limited | Professional & scientific | 2026 |
| Hangar 5 Trampoline Park Limited | Arts & recreation | 2015 |
| Hanoler Ltd | Other services | 2024 |
| Hapola Limited | Manufacturing | 2024 |
| Happy Paws Daycare Ltd | Arts & recreation | 2017 |
| Happyhouseliving Ltd | Extraterritorial | 2024 |
| Happysabi Ltd | Administrative & support | 2023 |
| Harbour HER CIC | Health & social care | 2025 |
| Hard to Find Foods Limited | Wholesale & retail | 2020 |
| Harkes Properties Limited | Real estate | 2018 |
| Harmony Core Ltd | Other services | 2023 |
| Harmonybeing Ltd | Extraterritorial | 2021 |
| Harvey Willoughby Investments Ltd | Real estate | 2000 |
| Haven Beach Views Ltd | Real estate | 2025 |
| Haven Diving Services Limited | Manufacturing | 2009 |
| Haven Home Rentals Limited | Real estate | 2026 |
| Haven Property Rentals Ltd | Real estate | 2025 |
| Haven Sports Limited | Wholesale & retail | 2002 |
| Haven Systems Global Limited | Information & communication | 2009 |
| Haven Systems Limited | Hospitality | 1998 |
| Haverfordwest Central Mosque Ltd | Other services | 2019 |
| Haverfordwest Chiropractic Limited | Health & social care | 2009 |
| Haverfordwest County A.F.C. | Arts & recreation | 2002 |
| Haverfordwest Estates Limited | Real estate | 1997 |
| Haverfordwest Festivals Ltd | Arts & recreation | 2022 |
| Haverfordwest Gymnastics Ltd | Other services | 2019 |
| Haverfordwest Heritage | Real estate | 2023 |
| Haverfortune Limited | Hospitality | 2024 |
| Haverhub C.I.C. | Hospitality | 2017 |
| Haverwarm GAS & OIL Ltd | Wholesale & retail | 2022 |
| Haworth Autobody Ltd | Wholesale & retail | 2017 |
| Hayguard Limited | Construction | 2007 |
| Hayston Business Park Ltd | Real estate | 2014 |
| Hayston Developments & Planning Ltd | Professional & scientific | 2010 |
| HCO SIR Penfro Limited | Other services | 2026 |
| HCS Training Ltd | Administrative & support | 2012 |
| HEALING4LIFE Ltd | Administrative & support | 2024 |
| Healthway UK Ltd | Wholesale & retail | 2009 |
| Hear OUR Voice Ltd | Arts & recreation | 2025 |
| Heart Evolution Healing Ltd | Administrative & support | 2025 |
| Heart Intelligent Business Ltd | Administrative & support | 2024 |
| Heart Intelligent Wealth Ltd | Extraterritorial | 2024 |
| Heart Loyalty Confidence Ltd | Extraterritorial | 2023 |
| Heartresponsibility Ltd | Administrative & support | 2022 |
| Hedley Asset Management Limited | Financial services | 1996 |
| Heitek Ltd | Other services | 2024 |
| Help at Home (Pembs) Ltd | Administrative & support | 2020 |
| Helping Hands Support Ltd | Health & social care | 2024 |
| HEM & TRS Ltd | Agriculture & fishing | 2016 |
| Hendre Eynon Farm Limited | Agriculture & fishing | 2002 |
| Hera Choice Private Limited | Wholesale & retail | 2026 |
| Herb Holdings Ltd | Financial services | 2024 |
| Herb's Homes Ltd | Real estate | 2021 |
| Herbal Properties LP | | 2017 |
| Herbrandston Dental Health Practice Limited | Health & social care | 2008 |
| Herbrandston Poultry Limited | Agriculture & fishing | 2020 |
| Here to Buy Repairs Ltd | Other services | 2014 |
| Herental Ltd | Other services | 2023 |
| Hewat Ltd | Other services | 2018 |
| HEY Printo Ltd | Wholesale & retail | 2022 |
| Heywood Electrical Ltd | Construction | 2019 |
| HH Renewables Ltd | Energy | 2015 |
| Hickies Music School | Education | 2022 |
| High on Adventure Limited | Education | 2005 |
| Highgrove Residential Care Limited | Administrative & support | 2005 |
| Hilde VON Bingen CYF | Extraterritorial | 2023 |
| Hillwest (Holdings) Limited | Financial services | 2024 |
| Hillwest Limited | Construction | 1992 |
| Hiraeth Developments Limited | Construction | 2017 |
| Hitchflicks Ltd | Information & communication | 2021 |
| HK NI House Ltd | Hospitality | 2024 |
| Hmbs Group Ltd. | Construction | 2015 |
| Hodo Solution Ltd | Other services | 2023 |
| Hofn Limited | Financial services | 2023 |