With trade and the environment becoming increasingly interconnected, environmental impact assessments (EIAs) of trade negotiations help to integrate environmental considerations into trade-related treaty making by evaluating potential risks and opportunities, addressing public concerns, and facilitating the introduction of response measures. Despite international efforts, such ‘trade EIAs’ have not yet been universally adopted. At the domestic level, the United States, Canada, and the European Union have pioneered the use of EIAs through their institutionalized procedures for over 20 years. This article examines and compares the relevant practices of these three jurisdictions to identify major patterns and to discuss the pros and cons of existing differences in this area. It argues that the time-tested experience of these jurisdictions could provide benchmarks for consideration in promoting the widespread implementation of trade EIAs through global and regional trade regimes.