| Giles Davies Developments Wales Ltd | Construction | 2023 |
| Giles Davies Holdings Limited | Financial services | 2021 |
| Giles Davies Limited | Construction | 2006 |
| Giles Davies Properties Ltd | Real estate | 2019 |
| Gileston Energy Limited | Other services | 2023 |
| Gillden Properties Ltd | Real estate | 2023 |
| Gilligans (Newport) Ltd | Hospitality | 2018 |
| Gillum Golf Limited | Arts & recreation | 2019 |
| Ginger Ninja Trickster Limited | Information & communication | 2015 |
| Ginger Rentals Limited | Real estate | 2024 |
| Gingersnap Consulting Limited | Information & communication | 2010 |
| Ginny Care Limited | Wholesale & retail | 2025 |
| Gippy Ltd | Professional & scientific | 2012 |
| Girl Torque Limited | Wholesale & retail | 2018 |
| Gisoni Limited | Other services | 2025 |
| Gist International Holdings Ltd | Financial services | 2026 |
| Gita Stores Limited | Wholesale & retail | 2007 |
| GJ Auto Service Ltd | Wholesale & retail | 2018 |
| GJ Oils IOW Ltd | Wholesale & retail | 2025 |
| GJC (IW) Ltd | Construction | 2011 |
| GJD Commercial Property Limited | Real estate | 2023 |
| GK Lighting Ltd | Arts & recreation | 2019 |
| GKE Property Ltd | Real estate | 2021 |
| GKE Ventures Ltd | Financial services | 2018 |
| GL Analytics Ltd | Professional & scientific | 2023 |
| GL100 Services Limited | Wholesale & retail | 2011 |
| Glacon Limited | Wholesale & retail | 2016 |
| Gladwin Consulting Ltd | Other services | 2011 |
| Glam HBT Ltd | Other services | 2021 |
| Glamair Supplies Limited | Wholesale & retail | 2009 |
| Glamorgan Roofing & Landscaping Ltd | Construction | 2026 |
| Glamorous by Nathan & Emma Ltd | Other services | 2026 |
| Glamping at Island Riding Centre Ltd | Hospitality | 2020 |
| Glan Llyn Football Club Ltd | Education | 2024 |
| Glanmere Ventures UK Limited | Wholesale & retail | 2026 |
| Glanvilles Damant Limited | Professional & scientific | 2017 |
| GLD School of Dance CIC | Arts & recreation | 2026 |
| Gleam & Glow Cleaning Ltd | Administrative & support | 2025 |
| Gleam Cleaning Services Ltd. | Households | 2008 |
| Glebe Construction (Newport) Limited | Construction | 2011 |
| Glebe Farm Holidays Limited | Hospitality | 2021 |
| Glebelands Cafe Ltd | Hospitality | 2024 |
| Glen Court Holdings Limited | Financial services | 2019 |
| Glen Court Transport Limited | Transport & logistics | 2019 |
| Glen Hall Property Management Limited | Real estate | 2011 |
| Glenbarrow Construction Ltd | Construction | 2018 |
| Glenfield Court (Management) Company Limited | Households | 1978 |
| Glenn Ward Limited | Construction | 2009 |
| Glinvesys Ltd | Agriculture & fishing | 2025 |
| Glitzyourbitz Limited | Other services | 2023 |
| GLJ Recycling Limited | Water & waste | 2007 |
| GLL Group Limited | Financial services | 2021 |
| GLM Social Studio Ltd | Professional & scientific | 2025 |
| GLO Construction & Developments Ltd | Construction | 2020 |
| Global Auto Ltd | Wholesale & retail | 2025 |
| Global Backup Solutions Limited | Professional & scientific | 2026 |
| Global Compassion International Limited | Financial services | 2021 |
| Global Expansion Partners Ltd | Professional & scientific | 2024 |
| Global Hospitality Corporation Limited | Administrative & support | 2020 |
| Global Insulated Structures Ltd | Construction | 2013 |
| Global Insulation Logistics Limited | Construction | 1999 |
| Global Market Shop Limited | Wholesale & retail | 2024 |
| Global Recycled Plastics Ltd | Manufacturing | 2019 |
| Global Sports Futures Group Limited | Arts & recreation | 2026 |
| Global Sports Futures Limited | Arts & recreation | 2015 |
| Global Sports Futures Pro Limited | Arts & recreation | 2026 |
| Global Tooling Solutions Limited | Manufacturing | 2012 |
| Global Tyres Limited | Wholesale & retail | 2020 |
| Global View Systems Limited | Manufacturing | 2003 |
| Globaldreambridge Ltd | Information & communication | 2026 |
| Globalwelsh CIC | Professional & scientific | 2016 |
| Globe Heating Ltd | Construction | 2017 |
| Glorious George Ltd | Wholesale & retail | 2024 |
| Glory's Global Services Ltd | Wholesale & retail | 2026 |
| Gloss Cartel Group Limited | Wholesale & retail | 2025 |
| Gloss Cartel Limited | Wholesale & retail | 2025 |
| Gloucester Railcar Trust Limited | Arts & recreation | 1996 |
| Glow Theroy Ltd | Other services | 2025 |
| GLOWBIT1 Ltd | Wholesale & retail | 2025 |
| Glwb Holdings Ltd | Real estate | 2023 |
| Glyn Rees Plumbing & Heating Services Limited | Manufacturing | 2003 |
| Glyn Rhys-Tyler Ltd | Professional & scientific | 2020 |
| Glyncwm Limited | Hospitality | 2024 |
| Glyndwr Consulting Ltd | Professional & scientific | 2018 |
| Glynhir 2025 Ltd | Extraterritorial | 2025 |
| Gmayers Services Ltd | Information & communication | 2021 |
| GMB Gwent Drylining Ltd | Construction | 2015 |
| GMK Dance Company Ltd | Education | 2022 |
| Gml(Llanmartin) Ltd | Real estate | 2025 |
| Gmqlmq Ltd | Health & social care | 2016 |
| GMS Fabrication Ltd | Manufacturing | 2023 |
| GMV22 Ltd | Transport & logistics | 2022 |
| Go Atom Limited | Financial services | 2024 |
| Go Electric (BIS) Limited | Administrative & support | 2024 |
| Go Electric (CHP) Limited | Energy | 2022 |
| Go Electric (EES) Ltd | Administrative & support | 2024 |
| Go Enviro Ltd | Construction | 2025 |
| Go Green Outdoor Designers Limited | Administrative & support | 2016 |
| Goamile Care Limited | Health & social care | 2021 |
| Gobs Care Limited | Health & social care | 2016 |