| Easypaynw Ltd | London | 2022 |
| Easywatt Ltd | Prestwick | 2026 |
| Eaton Electrical Solutions Ltd | Redcar | 2020 |
| Eaton-Upon-Tern Solar Limited | London | 2019 |
| Eaton-Williams Service Limited | Derby | 2022 |
| Eazy Breezy Ltd | London | 2023 |
| EB Farm Limited | Kinross | 2006 |
| Ebac Heat Pumps Ltd | Newton Aycliffe | 2025 |
| EBB Tide Investments Limited | Lymington | 2003 |
| Ebdon Air Ltd | Orpington | 2019 |
| Ebedei Holdings Limited | London | 2017 |
| Ebico Energy Ltd | Witney | 2020 |
| Ebico Trading Limited | Witney | 2015 |
| Ebis GB Holdings Limited | London | 2022 |
| Ebnal Lodge Solar Project Limited | Hove | 2014 |
| Ebohora Limited | London | 2026 |
| Ebpv Ltd | Edinburgh | 2023 |
| Ebroker Direct Limited | Bournemouth | 2017 |
| EBS Renewables Ltd | Goole | 2013 |
| EBS Venn Limited | Radstock | 2014 |
| EBS Wymeswold Limited | Reading | 2014 |
| EC Air Ltd | Dover | 2018 |
| EC Business Solutions Ltd | Northampton | 2016 |
| EC Electrical Contractors Ltd | Nottingham | 2026 |
| EC Renewables Ltd | Dundee | 2024 |
| Ecap Power Ltd | London | 2022 |
| Eccles Energy Centre Limited | Edinburgh | 2023 |
| Eccles Grid Stability Limited | London | 2018 |
| Ecclesgreen Limited | Fintona | 2013 |
| Echelonn HQ Limited | Lewisham | 2025 |
| Echo Energy Solutions Ltd | Oldham | 2022 |
| Echoing Hills Solar Ltd | Bath | 2023 |
| Echolite Electrics Limited | Sheffield | 2010 |
| ECI Power Limited | Chelmsford | 2025 |
| Eckland Lodge Solar Limited | Hove | 2016 |
| Eclectic Space Ltd | Bury St. Edmunds | 2008 |
| Eclipse Power Distribution Limited | Milton Keynes | 1992 |
| Eclipse Power Limited | Milton Keynes | 2015 |
| Eclipse Power Networks Limited | Milton Keynes | 2015 |
| Eclipse Power Optimise Future Point Limited | Milton Keynes | 2025 |
| Eclipse Power Optimise Thornwood Limited | Milton Keynes | 2025 |
| Eclipse Power Transmission Limited | Milton Keynes | 2015 |
| Eco 4 Energies Ltd | Leicester | 2024 |
| Eco AC Ltd | Poole | 2024 |
| Eco Air International Limited | London | 2019 |
| Eco Air Conditioning Limited | West Wickham | 2019 |
| Eco Air Conditioning Services Ltd | Ongar | 2022 |
| Eco Air Control Ltd | Derby | 2016 |
| Eco Apex Ltd | Hull | 2022 |
| Eco Breeze Air Conditioning Limited | Peterborough | 2022 |
| Eco Clean Energy Ltd | Basildon | 2026 |
| Eco Climate Control Limited | Kent | 2007 |
| Eco Coil Heating Ltd | Glasgow | 2008 |
| Eco Containers Limited | Edenfield | 2021 |
| Eco Cool AC Limited | Cardiff | 2025 |
| Eco Edge Renewables Ltd | London | 2024 |
| Eco Elec Ltd | Edinburgh | 2015 |
| Eco Energ Solutions Limited | Barnard Castle | 2007 |
| Eco Energy (U.K) Limited | London | 2021 |
| Eco Energy Generation Ltd | London | 2019 |
| Eco Energy Rating Ltd | Bolton | 2010 |
| Eco Energy Systems Ltd | Lincoln | 2024 |
| Eco Environment Resources UK Limited | Bromley | 2009 |
| Eco Filter Services Ltd | Rochdale | 2019 |
| Eco Force Climate Solutions Ltd | Doncaster | 2014 |
| Eco Green Management Limited | Leeds | 2009 |
| Eco Inpower Ltd | Burnley | 2024 |
| Eco Logic Corporate Limited | Gateshead | 2025 |
| Eco Logic Partners (Sunderland) Limited | Gateshead | 2025 |
| Eco Logic Partners Limited | Gateshead | 2014 |
| Eco Logic Solar Limited | Gateshead | 2020 |
| Eco Logic Trading Limited | Gateshead | 2025 |
| Eco Matters Renewable Assets Limited | Abingdon | 2016 |
| Eco Mirage Limited | Gloucester | 2014 |
| Eco Park J13 Limited | Stroud | 2018 |
| Eco Power Generation Limited | Newbury | 2019 |
| Eco Pro Renewables Limited | Exmouth | 2016 |
| Eco Social Energy Ltd | Birmingham | 2024 |
| Eco Solaris Limited | London | 2024 |
| Eco Sustainable Solutions Limited | Christchurch | 1995 |
| Eco Tech Group (South East) Limited | Basildon | 2023 |
| Eco Your Home (Fife) Ltd | Leven | 2019 |
| Eco-Comply Limited | Woking | 2006 |
| Eco-Friendly Electrical Ltd | London | 2017 |
| Eco-Lux Solutions Ltd. | Halifax | 2015 |
| Eco-Teh Limited | Weybridge | 2021 |
| Eco-Temp Air Conditioning Ltd | Fareham | 2024 |
| Eco-Vision Energy UK Limited | Saltcoats | 2022 |
| ECO2 Limited | Cardiff | 2004 |
| ECO2 LYG Limited | Cardiff | 2018 |
| ECO2 Wind and Power (Texas) Ltd | Cardiff | 2024 |
| ECO4FREE Ltd | Weymouth | 2025 |
| Ecoaer UK Ltd | London | 2017 |
| Ecobright Electrical Solutions Ltd | Halifax | 2016 |
| Ecocel 2 Ltd | Hamilton | 2015 |
| Ecocel Ltd. | Hamilton | 2009 |
| Ecocute Limited | Barnsley | 2010 |
| Ecodab Innovations Ltd | London | 2023 |
| Ecodev (Alyth) Holdings Ltd | London | 2021 |
| Ecodev (Alyth) Ltd | London | 2021 |