| Gareth Evans CYF | Agriculture & fishing | 2021 |
| Gareth Griffiths (Trydanwr) CYF | Construction | 2003 |
| Gelli Iago CYF | Agriculture & fishing | 2020 |
| Genius (Port) Limited | Wholesale & retail | 2021 |
| Genius (Porthmadog) Limited | Wholesale & retail | 2017 |
| Geraint Homes Ltd | Construction | 2013 |
| Gerddi Madryn Management Company Limited | Households | 2021 |
| Gethin Roberts CYF | Agriculture & fishing | 2013 |
| GIN Joint Ltd | Wholesale & retail | 2013 |
| Glampio Coed CYF | Hospitality | 2020 |
| Glandwr Healthcare Ltd | Health & social care | 2025 |
| Glanhau Cleaning Ltd | Administrative & support | 2024 |
| Glas Productions Limited | Administrative & support | 2009 |
| Glaslyn Bridge CYF | Households | 2005 |
| Global Training Consultancy Limited | Education | 2008 |
| Glosters Pottery Ltd | Manufacturing | 2021 |
| GLÔ Coaching CYF | Other services | 2025 |
| GMW Solutions Limited | Professional & scientific | 2016 |
| Godre'R Gest Porthmadog Ltd | Households | 2026 |
| Goleuo Llyn Lighting CYF | Wholesale & retail | 2016 |
| Goodmakers Furniture Ltd | Manufacturing | 2022 |
| Gorwel Dental Academy Limited | Health & social care | 2020 |
| Gorwel Specialist Medical Centre Ltd | Health & social care | 2025 |
| GR & TR Properties Limited | Households | 2013 |
| Graianog CYF | Agriculture & fishing | 2016 |
| Green Hire Limited | Extraterritorial | 2006 |
| Grey Slate & Stone Limited | Manufacturing | 2009 |
| GTA Diagnostix Limited | Wholesale & retail | 2017 |
| GVT CYF | Professional & scientific | 2021 |
| Gwenan M Hughes CYF | Health & social care | 2022 |
| Gwyliau Eryri - Snowdonia Holidays CYF | Hospitality | 2016 |
| Gwyn E CYF | Manufacturing | 2014 |
| Gwyn P Roberts Dairy CYF | Agriculture & fishing | 2025 |
| Gwyn Pritchard Property Rentals Ltd | Real estate | 2020 |
| Gwynedd Caravans Limited | Extraterritorial | 2019 |
| Gwynedd Slate Ltd | Extraterritorial | 2009 |
| Gwynedd Van Conversions Limited | Manufacturing | 2020 |
| H G Jones Holiday LET Ltd | Hospitality | 2019 |
| H West Ltd | Construction | 2023 |
| H.J. Projects Limited | Real estate | 2009 |
| H2H Consulting Ltd | Professional & scientific | 2024 |
| Hadfer Limited | Hospitality | 2017 |
| Hamdden Caravans Limited | Manufacturing | 2017 |
| Hand Dyed Sofa Company Limited | Manufacturing | 2015 |
| Hardd Holdings Limited | Real estate | 2022 |
| Hari Roberts Groundworks CYF | Construction | 2017 |
| Harlech Toyota Limited | Extraterritorial | 2010 |
| HEN Fecws Maintenance Limited | Households | 1986 |
| Hike and Bike Snowdonia / Heicio a Beicio Eryri CYF | Administrative & support | 2021 |
| Home Farm Anglesey Limited | Hospitality | 2015 |
| Honco Bonco CYF | Wholesale & retail | 2017 |
| Hughes AI Gwmni CYF | Construction | 2018 |
| Hunto Hospitality Ltd | Hospitality | 2024 |
| HUW CYF | Administrative & support | 2025 |
| Iard Nefyn CYF | Administrative & support | 2020 |
| Igam Ogam 44 Ltd | Other services | 2024 |
| Illw CYF | Administrative & support | 2016 |
| Inhaus Property Ltd | Real estate | 2024 |
| Iori Limited | Professional & scientific | 2008 |
| Iwan Thomas Feeds Limited | Manufacturing | 2018 |
| J Humphreys & Co Ltd | Administrative & support | 2017 |
| J M Hughes A'I Feibion CYF | Wholesale & retail | 2014 |
| J O Jones CYF | Agriculture & fishing | 2011 |
| J. Jones & SON Holdings Ltd | Financial services | 2026 |
| J.Jones & SON Butchers Ltd | Wholesale & retail | 2026 |
| J.Jones & SON Property Ltd | Real estate | 2026 |
| JEN Hospitality Ltd | Hospitality | 2024 |
| Jese Properties Limited | Real estate | 2016 |
| Jklsoar Limited | Hospitality | 2014 |
| JKM Cleaning Services Limited | Administrative & support | 2020 |
| Jones & Jones Steel Fabrication Limited | Manufacturing | 2022 |
| Jones Farming Ltd | Agriculture & fishing | 2025 |
| JOS Homes Limited | Financial services | 2023 |
| JTW Carpentry and Tiling Ltd | Construction | 2020 |
| JW Health & Physio Limited | Health & social care | 2004 |
| Kacel Ltd | Extraterritorial | 2013 |
| Kemble Cleaners Ltd | Administrative & support | 2018 |
| Keristrum Limited | Agriculture & fishing | 2018 |
| Kirk Lewis Holdings Limited | Administrative & support | 2014 |
| Kopa Marketing Ltd | Information & communication | 2019 |
| L G Roberts Plant Hire Ltd | Administrative & support | 2015 |
| L Morgan CYF | Administrative & support | 2024 |
| Lafant CYF. | Hospitality | 2021 |
| Laurence House (Felinheli) Management Company Limited | Households | 2017 |
| LEO Mason Consulting Limited | Professional & scientific | 2009 |
| Lifeguard UK Limited | Professional & scientific | 2012 |
| Limonar Properties Limited | Professional & scientific | 2013 |
| Lledar CYF. | Wholesale & retail | 2017 |
| Llefrith Nant CYF | Manufacturing | 2021 |
| Llesiant Llyn CYF | Other services | 2025 |
| Llwyni'R ŴYN CYF | Construction | 2018 |
| Llyn Access Scaffolding Ltd | Construction | 2024 |
| Llyn Aqua Research Limited | Agriculture & fishing | 2005 |
| Llyn Aquaculture Limited | Agriculture & fishing | 1999 |
| Llyn Leisure Ltd | Real estate | 2021 |
| Llys Emrys (2015) RTM Company Limited | Hospitality | 2015 |
| Llys Emrys Apartments CYF | Real estate | 2008 |
| LM Residential Management Ltd | Real estate | 2012 |
| LTE Stock Limited | Agriculture & fishing | 2024 |
| Lyons & Roberts Laundry Ltd | Other services | 2023 |