| Entity Dining Ltd | Other services | 2024 |
| Envico Engineering Limited | Manufacturing | 1976 |
| Envico Holdings Limited | Financial services | 2025 |
| Envico Services Limited | Administrative & support | 2008 |
| Environ Mining (UK) Limited | Professional & scientific | 2012 |
| Enviroteq Limited | Manufacturing | 2011 |
| Envirovoid Limited | Manufacturing | 2024 |
| Envision Juice Bar Ltd | Hospitality | 2025 |
| Enzyme Research Laboratories Limited | Professional & scientific | 1993 |
| EON Estates Limited | Construction | 2016 |
| EP Downes Limited | Financial services | 2022 |
| EP Optical Ltd | Health & social care | 2023 |
| Epcwales Ltd | Administrative & support | 2020 |
| Ephesus 1907 Ltd | Hospitality | 2026 |
| Epicure Catering Events Ltd | Hospitality | 2019 |
| EPS Construction Ltd | Construction | 2005 |
| EPS EV Ltd | Construction | 2024 |
| Equal Education Partners Ltd | Administrative & support | 2011 |
| Equilibrium Consultancy Ltd | Health & social care | 2021 |
| Equiosteo Limited | Health & social care | 2022 |
| Equipment Services & Engineering Limited | Manufacturing | 2003 |
| Equipped Stewards Limited | Information & communication | 2023 |
| ER4 Ltd | Construction | 2025 |
| ERA Construction & Civil Engineering Ltd | Construction | 2022 |
| ERA Property Limited | Real estate | 2019 |
| Erbautista Care Limited | Health & social care | 2017 |
| ERC Solutions Ltd | Information & communication | 2019 |
| ERG Accounting Ltd | Professional & scientific | 2024 |
| Erinstone Ltd | Construction | 2017 |
| Ernest Williams (Contractors) Limited | | 1946 |
| Ernie’S Coffee Ltd | Hospitality | 2024 |
| Eruptor UK Limited | Professional & scientific | 2021 |
| ERV Holdings Ltd | Health & social care | 2021 |
| Eryri Lettings Ltd | Real estate | 2023 |
| ES Engineering Swansea Ltd | Professional & scientific | 2024 |
| ES Partnership Limited | Financial services | 2018 |
| Es&M Limited | Health & social care | 2019 |
| Escape Yoga Ltd | Health & social care | 2023 |
| ESCAPE2VAPE Ltd | Wholesale & retail | 2016 |
| ESD Consulting Ltd | Professional & scientific | 2026 |
| Eshopbargains Ltd | Wholesale & retail | 2019 |
| Esja Property Development Limited | Real estate | 2024 |
| ESM Commercials Ltd | Wholesale & retail | 2019 |
| Esmail Neurology Ltd | Health & social care | 2022 |
| Esos Services Ltd | Construction | 2021 |
| Essentia Global Limited | Administrative & support | 2022 |
| Essentia Matters Limited | Professional & scientific | 2014 |
| Essential Risk Solutions Ltd | Financial services | 2010 |
| Essentielle CIC | Health & social care | 2026 |
| Essex Psychology Group Limited | Health & social care | 2017 |
| Estate Capital Financial Management Limited | Financial services | 2003 |
| Estate Capital Investment Management Limited | Financial services | 2005 |
| Estate Capital Wealth Management Limited | Administrative & support | 2018 |
| Estates Management Cymru Limited | Agriculture & fishing | 2006 |
| Estateways Holdings Limited | Financial services | 2024 |
| Estateways Limited | Real estate | 1924 |
| Este Cafeteria Ltd | Hospitality | 2025 |
| Estib Ltd | Real estate | 2023 |
| Estuary Scaffolding and Roofing Ltd | Construction | 2020 |
| Estuary View Properties Ltd | Real estate | 2025 |
| Esus Services Limited | Administrative & support | 2015 |
| ET Cherry Limited | Wholesale & retail | 2022 |
| ETC Commercial Cleaning Ltd | Administrative & support | 2019 |
| Eternal Elegance Limited | Health & social care | 2024 |
| Eternity Fire and Security Ltd | Energy | 2022 |
| Ethelred Land Limited | Real estate | 2018 |
| Ethical Energy (UK) Ltd | Energy | 2011 |
| Ethnic Youth Support Team | Other services | 2008 |
| Ethos Swansea Limited | Administrative & support | 2005 |
| Etifeddiaeth Translating CYF. | Professional & scientific | 2026 |
| Etlr Ltd | Information & communication | 2025 |
| ETM 4 UK Ltd | Transport & logistics | 2022 |
| Ettanity Concept Ltd | Health & social care | 2022 |
| Eukrasia Laboratories Ltd | Information & communication | 2026 |
| Eurasian Tandoori Ltd | Hospitality | 2019 |
| Euro Electrical Wholesalers Limited | | 1972 |
| Euro Equipment Limited | Wholesale & retail | 1985 |
| Euro Mini Store Limited | Wholesale & retail | 2025 |
| Eurobeauty Limited | Wholesale & retail | 2015 |
| Europa Distribution Ltd | Manufacturing | 2012 |
| Europa Marketing (UK) Ltd | Manufacturing | 2012 |
| Europa Musical Instruments Ltd | Manufacturing | 2012 |
| Europa Sales Ltd | Wholesale & retail | 2025 |
| European Coach Services Limited | Administrative & support | 2013 |
| European Soil and Water Engineering Group Ukeig | | 2015 |
| European Sweets & Snacks Limited | Financial services | 2025 |
| Euroyachts (Newco) Limited | Wholesale & retail | 2020 |
| Eutopia Investments (SW) Limited | Construction | 2018 |
| Ev-Tower Ltd | Manufacturing | 2020 |
| EV5 Property Limited | Real estate | 2024 |
| EVA Ashley Bridal Limited | Wholesale & retail | 2018 |
| EVA Swan Trading Ltd | Wholesale & retail | 2025 |
| Evan Rees (Butter) Limited | Manufacturing | 1989 |
| Evan Rees Holdings Limited | Real estate | 1996 |
| Evan Thomas & Sons Ltd | Professional & scientific | 2016 |
| Evans & Co GEO Services Ltd. | Professional & scientific | 2025 |
| Evans & Fitzgerald Limited | Administrative & support | 1992 |
| Evans Accountancy Ltd | Professional & scientific | 2026 |
| Evans Bros. (Haulage) Limited | Transport & logistics | 1965 |
| Evans Building Contractors Limited | Construction | 2013 |