 This study quantifies the regional differences in air quality responses to aviation emissions and analyzes their drivers using the GeoS chemistry atmospheric chemistry transport model. The study finds that a unit of fuel burn mass over Europe results in 45% and 50% higher global health impacts than a unit of fuel burn mass over Asia and North America, respectively, with 73% and 88% of health impacts from aviation emissions over Europe and North America occurring outside the region of emission. These findings suggest that inter-regional effects and differences in regional response to emissions should be taken into account when considering policies to mitigate air quality impacts from aviation. This article was authored by Flavio de Equadros, Mir Jamsnelin, and Irene CDDC.