ECA
- ACES Educational Center for the Arts
- António Eça de Queiroz
- António Júlio da Costa Pereira de Eça
- Bureau of Educational and Cultural Affairs
- Captain-major
- Central Asia
- Duarte de Eça
- ECA International
- ECA Records
- ECA stack
- Easington Catchment Area
- Ecologically Critical Area
- Economic Commission for Africa
- Economic Cooperation Administration
- Edinburgh College of Art
- Education Corporation of America
- Electoral Count Act
- Electrical Contractors' Association
- Electronic Industries Alliance
- Elementary cellular automaton
- Emergency care assistant
- Emission Control Area
- Emmanuel Christian Academy (Ohio)
- Encana
- Engineering Critical Assessment
- Enterobacterial common antigen
- Enterprise Collaboration Architecture
- Entertainment Consumers Association
- Escuela Campo Alegre
- Essential Commodities Act
- Ethyl cyanoacrylate
- Eurocypria Airlines
- Euroleague Commercial Assets
- Europe
- European Canoe Association
- European Chips Act
- European Club Association
- European Coastal Airlines
- European Cockpit Association
- European Communist Action
- European Communities Act 1972 (Ireland)
- European Communities Act 1972 (UK)
- European Court of Auditors
- European Crystallographic Association
- Evangel Christian Academy
- Evangelical Christian Academy (Madrid, Spain)
- Evangelical Church Alliance
- Event condition action
- Executive Council of Alberta
- Export credit agency
- External carotid artery
- Eça de Queiroz
- Ferdinand of Portugal, Lord of Eça
- Filipa de Eça
- Joana de Eça
- John, Duke of Valencia de Campos
- Luiz Eça
- Portuguese Ceylon
- School of Communications and Arts, University of São Paulo
- United Nations Economic Commission for Africa
- World Bank