ECN may refer to:
Organizations, companies
- ECN (TV station), now NEN, in New South Wales, Australia
- ECN Capital, a Canadian financing company
- Electoral Commission of Namibia
- Energy Research Centre of the Netherlands (Dutch: Energieonderzoek Centrum Nederland)
- Environmental Change Network, of the British Natural Environment Research Council
- Ercan International Airport, in Northern Cyprus
- European Competition Network
- European Crowdfunding Network
Computing
- Electronic communication network
- Explicit Congestion Notification
- Encoding Control Notation
Other
- Electrochemical noise
- Engineering change notice
- Enhanced capital note
- Eastman Color Negative