| Eighteen Forty Stamp Company Limited | Wholesale & retail | 2011 |
| Eighty Twenty People Ltd | Professional & scientific | 2018 |
| EKC Construction and Design Ltd | Construction | 2023 |
| EKP Software Limited | Information & communication | 2013 |
| Ekren's Limited | Information & communication | 2021 |
| Elaine & Anna Ltd | Wholesale & retail | 2024 |
| Elara Recruitment Ltd | Administrative & support | 2024 |
| Electrodetection Limited | Professional & scientific | 2007 |
| Elevate Business Success Ltd | Education | 2024 |
| Eliot Place (Harpenden) Management Limited | Real estate | 2013 |
| Elite Coffee Holdings Limited | Hospitality | 2018 |
| Elite Coffee Limited | Hospitality | 2016 |
| Elite Entertainment Services Limited | Administrative & support | 2026 |
| Elite Tutors Harpenden Ltd | Education | 2025 |
| Ellamax Ltd | Extraterritorial | 2007 |
| Ellerd Investments Limited | Financial services | 1960 |
| Ellis Bourne Consulting Limited | Professional & scientific | 2007 |
| Elliswick Lawn Tennis Club Limited | Arts & recreation | 2016 |
| ELM Court (Watford) Limited | Households | 2004 |
| ELM Walk Management Limited | Households | 2011 |
| ELS360 Limited | Information & communication | 2025 |
| Elsa Wren Ltd | Other services | 2025 |
| Elsewhere (UK) Limited | Administrative & support | 2012 |
| Elstree Homes Limited | Real estate | 2015 |
| EM & ME Designs Limited | Information & communication | 2010 |
| Emay Construction Limited | Construction | 2020 |
| Emerald Spring Services Ltd | Manufacturing | 2008 |
| EMG Solutions Ltd | Information & communication | 2025 |
| Emily Court Management (Harpenden) Limited | Households | 2005 |
| Emily Jackman Creative Ltd | Professional & scientific | 2025 |
| Emily's Free From Food Limited | Hospitality | 2026 |
| Emily's Homewares Ltd | Wholesale & retail | 2023 |
| Emily's Mats Ltd | Wholesale & retail | 2021 |
| Emma Mapletoft Imaging Limited | Professional & scientific | 2021 |
| Emma Rothwell Limited | Wholesale & retail | 2022 |
| Emotionally Focused Training Ltd | Education | 2019 |
| Endeavour OIL & GAS | | 1999 |
| Energy Park Limited | Wholesale & retail | 2021 |
| Energy Power Consultancy Ltd | Construction | 2025 |
| Engenera Project 1 Limited | Construction | 2019 |
| Engenera Project 2 Limited | Financial services | 2019 |
| Engenera Project 3 Limited | Financial services | 2019 |
| Engenera Project 4 Limited | Financial services | 2019 |
| Engenera Project 5 Limited | Energy | 2019 |
| Engenera Project 6 Limited | Energy | 2019 |
| Engenera Solar Recoveries Limited | Administrative & support | 2025 |
| Enigmalytics Limited | Professional & scientific | 2015 |
| Enolam Films Ltd | Information & communication | 2023 |
| Entres Ltd | Hospitality | 2016 |
| Entwurf Limited | Professional & scientific | 2009 |
| Envi Consulting and Investments LLC (UK) Limited | Wholesale & retail | 2023 |
| Epstein House Limited | Wholesale & retail | 2016 |
| EQ Finance Limited | Information & communication | 2009 |
| Equine Discovery Ltd | Professional & scientific | 2026 |
| Equine Laundry Specialists Limited | Administrative & support | 2013 |
| Equity Edge Analytics Ltd | Information & communication | 2023 |
| Erel Tutoring Ltd | Education | 2020 |
| Ereon Business Limited | Professional & scientific | 2003 |
| Erica Investments Ltd | Professional & scientific | 2018 |
| Erris View Ltd | Wholesale & retail | 2025 |
| Erskine Advisory Limited | Professional & scientific | 2025 |
| Erys AI Ltd | Information & communication | 2024 |
| ESF Design Ltd | Professional & scientific | 2025 |
| ESK International Ltd | Wholesale & retail | 1978 |
| Etailxperts Limited | Information & communication | 2002 |
| Ethical Kind Ltd | Wholesale & retail | 2019 |
| Ethonomia Limited | Administrative & support | 2016 |
| Etoceto Investments Limited | Real estate | 2022 |
| Etrips Global Limited | Information & communication | 2021 |
| Europounds Ltd | Financial services | 2023 |
| EV2AV Limited | Professional & scientific | 2018 |
| Evbi Projects Ltd | Real estate | 2019 |
| Evergreen Children's Residential Limited | Health & social care | 2026 |
| Eversleigh Accounting Services Limited | Financial services | 2015 |
| Everyday Management Consultancy Limited | Administrative & support | 2022 |
| Everything Innovations Ltd | Professional & scientific | 2025 |
| Evets Consulting Limited | Professional & scientific | 2012 |
| Evoform Limited | Information & communication | 2012 |
| Evolvy Workshop Community Ltd | Wholesale & retail | 2019 |
| Evops Limited | Information & communication | 2016 |
| Evorintel Consulting Limited | Professional & scientific | 2015 |
| Evovation Limited | Professional & scientific | 2008 |
| EX11 Group Limited | Financial services | 2021 |
| Exact Lifestyle Ltd | Arts & recreation | 2024 |
| Exam Whisperer Ltd | Education | 2025 |
| Exlservice (UK) Limited | Administrative & support | 2003 |
| Extremely Successful Creative Ltd | Professional & scientific | 2024 |
| EYE Q Ltd | Professional & scientific | 2015 |
| Eyedeology Limited | Manufacturing | 2010 |
| Eyes on the Horizon Ltd | Arts & recreation | 2026 |
| F36 Limited | Professional & scientific | 2024 |
| F451DIGITAL Limited | Information & communication | 2025 |
| F9 Research Limited | Information & communication | 2016 |
| FAB Controls Ltd | Information & communication | 2011 |
| Fabri AI Ltd | Information & communication | 2022 |
| Fairfield Hall Management Company Limited | Households | 2004 |
| FAIRWAY24 Ltd | Arts & recreation | 2026 |
| Fallows Green Limited | Households | 2000 |
| Family Matters Assessment Centres Ltd | Health & social care | 2026 |
| Fancy Dress Express Limited | Wholesale & retail | 2016 |