| First Class Windows, Doors and Conservatories Ltd | Extraterritorial | 2025 |
| Fitta Floor Limited | Wholesale & retail | 2004 |
| Fiture Clothing Ltd | Manufacturing | 2016 |
| Five Star Fish Bar (Port Talbot) Ltd | Wholesale & retail | 2021 |
| Fixmyvroom Ltd | Wholesale & retail | 2025 |
| FJF Properties Limited | Real estate | 2026 |
| FKL Pumping Solutions Ltd | Professional & scientific | 2023 |
| Flame&Bake Ltd | Hospitality | 2024 |
| Flexible Assessment and Training Services Ltd | Construction | 2020 |
| Flirty Ltd | Information & communication | 2022 |
| Fmde Ltd | Manufacturing | 2022 |
| Focused Minds C T Limited | Education | 2017 |
| Folk Soap Ltd | Manufacturing | 2024 |
| Folland Enterprises Limited | Administrative & support | 2002 |
| Folland Home Improvements Limited | Construction | 2001 |
| Folland Joinery Limited | Extraterritorial | 1997 |
| FOOD2GOOO Limited | Wholesale & retail | 2025 |
| Foraging Ahead Ltd | Agriculture & fishing | 2024 |
| Foredowel Holdings Ltd | Financial services | 2019 |
| Foredowel Lifting Services Limited | Manufacturing | 2025 |
| Foredowel Limited | Manufacturing | 1981 |
| Foredowel Mechanical Services Ltd | Manufacturing | 2023 |
| Forest Lodge Lane Developments Limited | Construction | 2014 |
| Forest Lodge Lane Estates Limited | Construction | 2014 |
| Forkbeard Films Ltd | Information & communication | 2017 |
| Fourteentwentyeight Ltd | Wholesale & retail | 2024 |
| Frame Form Ltd | Manufacturing | 2025 |
| Francis Hutchinson Investments Ltd | Real estate | 2019 |
| Francis Hutchinson Properties Limited | Real estate | 2019 |
| Frankie’S Desserts Baglan Ltd | Hospitality | 2019 |
| Freedom Media Holdings Limited | Wholesale & retail | 2026 |
| Freedom School of Motoring Ltd | Education | 2024 |
| Fresh Curry House Ltd | Hospitality | 2020 |
| Freshmeasure Ltd | Professional & scientific | 2024 |
| Freudenberg Flow Technologies Limited | Manufacturing | 1991 |
| Front ROW Autos Ltd | Wholesale & retail | 2025 |
| Front ROW Properties Limited | Real estate | 2015 |
| Fstep Services Ltd | Information & communication | 2019 |
| Funky Footsteps Day Nursery Limited | Health & social care | 2019 |
| Fusion Solar & Battery Limited | Energy | 2022 |
| FWS Services Ltd | Water & waste | 2024 |
| G & L Staircases Limited | Manufacturing | 2010 |
| G B Enoch & Co Limited | Administrative & support | 2016 |
| G Hopkins Installations Ltd | Construction | 2017 |
| G O'Neill Engineering Services Ltd | Professional & scientific | 2018 |
| G Ville Ltd | Financial services | 2023 |
| G-Force Transportation Ltd | Transport & logistics | 2025 |
| G.A.Thornepropertyservices Ltd | Real estate | 2026 |
| GA Plumbing & GAS Ltd | Construction | 2023 |
| Gaga Jouet Ltd | Wholesale & retail | 2025 |
| Gardner Tankage Ltd | Administrative & support | 2026 |
| Gariban 27 Ltd | Hospitality | 2024 |
| Gate House Self Storage Ltd | Real estate | 2021 |
| Gatherington Valley Ltd | Wholesale & retail | 2025 |
| GBV Properties Limited | Real estate | 2012 |
| Gear-Trodes (South Wales) Limited | Wholesale & retail | 1978 |
| GEM T D Properties Ltd | Real estate | 2024 |
| Genc Catering Limited | Hospitality | 2022 |
| Gentle Care (Holdings) Limited | Financial services | 2022 |
| Gentle Care Services Limited | Public administration | 2019 |
| GGE Group Ltd | Real estate | 2023 |
| GGL Autos Ltd | Wholesale & retail | 2021 |
| Gill 1 Limited | Real estate | 2012 |
| GJB Property Services Ltd | Real estate | 2019 |
| Glais Valley Equestrian Ltd | Arts & recreation | 2026 |
| Glali Vape Ltd | Wholesale & retail | 2025 |
| Glamorgan Glazing Limited | Administrative & support | 2011 |
| Glamorgan Property Investments Ltd | Professional & scientific | 1996 |
| Glasfryn Kennels Ltd | Agriculture & fishing | 2022 |
| Glasslights Limited | Health & social care | 1986 |
| Glenn's Deliveries Ltd | Transport & logistics | 2025 |
| Glowify Limited | Wholesale & retail | 2025 |
| Glue Films Ltd | Extraterritorial | 2015 |
| Glyncorrwg MOT Centre Ltd | Wholesale & retail | 2004 |
| Glyncorrwg Mountain Bike Centre & Campsite Ltd | Hospitality | 2020 |
| Glyncorrwg RFC Limited | Arts & recreation | 2019 |
| GMO Limited | Other services | 2023 |
| Go & BO Holdings Ltd | Financial services | 2025 |
| Go Cleaning Service Limited | Administrative & support | 2021 |
| Go Property Maintenance Ltd | Construction | 2023 |
| Goalgetters Soccer School CIC | Arts & recreation | 2023 |
| Gofal Plant Tregeles Ltd | Education | 2023 |
| Golcuk Ltd | Hospitality | 2025 |
| Golden Gathering Ltd | Hospitality | 2015 |
| Golf Tango Sierra Ltd | Transport & logistics | 2014 |
| Goliath Properties (Wales) Ltd | Real estate | 2015 |
| Gomer & DAP Holdings Limited | Professional & scientific | 2014 |
| Gomilogo Ltd | Wholesale & retail | 2025 |
| Gopix Limited | Other services | 2020 |
| Gorwel Limited | Professional & scientific | 2024 |
| Gossip Cafe Ltd | Hospitality | 2025 |
| Gourlay Hire Limited | Construction | 1992 |
| Goytre Leisure Holdings Limited | Hospitality | 2017 |
| Goytre United Football Club Ltd | Arts & recreation | 2024 |
| GP Carpentry & Maintenance Limited | Construction | 2014 |
| Grab and Go for Muck Away Limited | Transport & logistics | 2023 |
| Grand 27 Ltd | Professional & scientific | 2019 |
| Grand Sultan One Ltd | Hospitality | 2017 |
| Grassificial Limited | Other services | 2015 |
| Green Cleaning Limited | Administrative & support | 2021 |