| Emtrek Developments Ltd | Construction | 2020 |
| Emtrek Ltd | Construction | 2015 |
| Emtrek Property Developments Limited | Construction | 2022 |
| Encon Engineering (UK) Limited | Manufacturing | 2010 |
| Endeavour Solutions (UK) Limited | Construction | 2009 |
| Energy South Electrical Limited | Manufacturing | 2013 |
| Energy South Property Limited | Real estate | 2018 |
| Enes Foods Ltd | Hospitality | 2019 |
| Enigma Commercial Investments Ltd | Administrative & support | 2016 |
| Envirotecc Limited | Construction | 2025 |
| Epc-Nearme Limited | Information & communication | 2022 |
| Epsilon Test Services Limited | Administrative & support | 1995 |
| Eriez Investments Limited | Professional & scientific | 2010 |
| Eriez Magnetics Europe Limited | Manufacturing | 1978 |
| ESC Installations Ltd | Construction | 2017 |
| ETP Law Limited | Extraterritorial | 2023 |
| Etrader Websites Limited | Information & communication | 2011 |
| ETS Cymru Limited | Construction | 2007 |
| European Investments (UK) Limited | Real estate | 2001 |
| Eurosolve Limited | Information & communication | 1994 |
| EV Engineering Limited | Professional & scientific | 2016 |
| Evan Johnson Ltd | Administrative & support | 2026 |
| Evans Prop Co Ltd | Financial services | 2022 |
| Evanslegacyholdings Ltd | Real estate | 2025 |
| Evermore Print Solutions Ltd | Professional & scientific | 2024 |
| Evertrek Events Limited | Hospitality | 2021 |
| Evolve Solutions Group Ltd | Real estate | 2008 |
| Ewart Estates Limited | Real estate | 2016 |
| Excellence Hospitality Ltd | Hospitality | 2022 |
| Excellence IT (Trustee) EOT Ltd | Professional & scientific | 2024 |
| Excellence IT (UK) Limited | Information & communication | 2007 |
| Excellence Supplies Ltd | Wholesale & retail | 2021 |
| Export Case Company Limited | Manufacturing | 2000 |
| Extra Hands Homecare Limited | Other services | 2025 |
| Ezna Ltd | Construction | 2025 |
| F Mills Limited | Construction | 2018 |
| Fabrication & Erection UK Limited | Construction | 2010 |
| Facilities Maintenance Solutions Ltd | Administrative & support | 2023 |
| Fairway Window Systems Limited | Construction | 2017 |
| Faith Superstore Limited | Wholesale & retail | 2014 |
| Family Life CIC | Hospitality | 2018 |
| FAR Horizon Properties Ltd | Real estate | 2020 |
| FAR Horizon Ventures Ltd | Construction | 2025 |
| Farmingfutura Ltd | Professional & scientific | 2026 |
| Fayscooks Ltd | Wholesale & retail | 2025 |
| Fecci Properties Ltd | Real estate | 2013 |
| Ferns Day Nursery Ltd | Health & social care | 2025 |
| Fess Training Group Limited | Education | 2024 |
| Fessqual Limited | Education | 2021 |
| Fibreon Flat Roofing Ltd | Construction | 2026 |
| Filly Taxis Ltd | Transport & logistics | 2012 |
| Financial Chain Corporation PC | | 2018 |
| Finexample Limited | Manufacturing | 1995 |
| Finla Coffee Limited | Hospitality | 2014 |
| Finlayson Consulting Limited | Professional & scientific | 2018 |
| Finn Bristow Professional Services Limited | Professional & scientific | 2023 |
| Fire Doors by Solar Limited | Manufacturing | 2018 |
| Fire Industry Training Academy Limited | Education | 2021 |
| Fire Safety Group Limited | Extraterritorial | 2016 |
| Firecycle Limited | Water & waste | 2025 |
| Firefly Press Limited | Information & communication | 2018 |
| Firerite (UK) Limited | Manufacturing | 1999 |
| Fireshield Electrical Systems Limited | Administrative & support | 2009 |
| Fireshield Sprinklers Limited | Construction | 2002 |
| First Action Properties Ltd | Real estate | 2021 |
| First Call GAS Assessments Ltd | Other services | 2017 |
| First Fleet Limited | Transport & logistics | 2017 |
| First Triumph Kensington Healthcare Ltd | Health & social care | 2018 |
| Fish Factory Bedwas Ltd | Hospitality | 2018 |
| Fishpro Ltd | Hospitality | 2020 |
| FIT4LIFE Coaching Limited | Arts & recreation | 2022 |
| Fitfitshop Ltd | Wholesale & retail | 2019 |
| Flare Heating Ltd | Construction | 2025 |
| Flavours of Jollof Ltd | Wholesale & retail | 2025 |
| Fleetility Limited | Administrative & support | 2026 |
| Fletchers Motor Company Limited | Wholesale & retail | 2002 |
| Flippin' Welsh Cakes Limited | Manufacturing | 2024 |
| Flowhouse Studio Ltd | Arts & recreation | 2026 |
| Floxx Labs Limited | Professional & scientific | 2024 |
| Flying Camera Crew Limited | Information & communication | 2013 |
| Fooks & Co Limited | Professional & scientific | 2001 |
| Footsteps Day Nurseries (South Wales) Limited | Health & social care | 2020 |
| Footsteps Nurseries (Wales) Limited | Health & social care | 2006 |
| Formosa Films Limited | Information & communication | 2021 |
| Fortify Physiotherapy Ltd | Health & social care | 2025 |
| Fotheringham Associates Limited | Information & communication | 2011 |
| Four Minutes Limited | Wholesale & retail | 2017 |
| Four Square PUB Co Ltd | Hospitality | 2013 |
| Four Thirty Limited | Professional & scientific | 2025 |
| Foxhound Home Clearance Ltd | Transport & logistics | 2025 |
| Frenchman's Creek Limited | Financial services | 2017 |
| FTL Transport Ltd | Transport & logistics | 2022 |
| Full Marks Educational Consultancy Limited | Education | 2012 |
| Fusion Occupational Health Limited | Health & social care | 2016 |
| Future-Tech Gaming Ltd | Arts & recreation | 2015 |
| Futureform Spaces Limited | Construction | 2025 |
| G & a Property Developments Limited | Real estate | 2014 |
| G & S Decorite (Cardiff) Limited | Construction | 1999 |
| G ANN Healthcare Limited | Health & social care | 2021 |
| G Debono Electrical Services Ltd | Energy | 2017 |