In most education systems, students with an immigrant background perform worse academically than do native students. However, in the United Arab Emirates (UAE) differences emerge in the opposite direction and the national-expatriate gap in academic performance is equivalent to almost three years of schooling. This gap is a concern in the UAE, where national students mainly attend public schools while expatriates mostly attend private schools. In this study, to investigate the performance gap between national and expatriate students we estimate group differences and conduct linear regression analysis using data from the 2018 Programme for International Student Assessment. Results show that the gap varies by emirate and country of origin, and is greater among boys, better-off students and those attending private schools. Between 33% and 47% of this gap is explained by school type, whether public or private. We offer recommendations for the UAE that may also be useful for other high expatriate recruiting nations in development; however, in a country characterized by 85% expatriates and a maturing education policy, challenges remain.