The Iran–Iraq border region, located along the Zagros fold-and-thrust belt, is one of the most active seismic zones within the Arabia–Eurasia collision belt. Over the past two decades, this region has experienced several moderate to large earthquakes, most notably the 2017 Mw 7.3 Ezgeleh–Halabja event, which highlighted the seismic hazard for border cities in both countries. In this paper, the tectonic framework and seismicity pattern of the border region are first described. Then, based on seismotectonic studies of the Badra–Amarah and Khanaqin faults and recent probabilistic seismic hazard assessment (PSHA) results for Iraq, the seismic implications for border cities and critical infrastructures on both sides of the boundary are examined. The results indicate that the highest seismic hazard levels for long return periods occur in northern and northeastern Iraq, in the vicinity of the active border faults, emphasizing the necessity of a joint Iran–Iraq revision of seismotectonic zoning, seismic design codes, and early warning and emergency response systems.

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