Social trust is linked to many desirable economic and social outcomes. Using new data from a representative sample of 2,668 Swedish expatriates, we examine the robustness of high social trust in countries with different levels of institutional quality. The results suggest that individual trust decreases with length of stay in countries with high corruption and low rule of law. The effect is relatively small and driven by expatriates who were aged 30 years or below upon arrival to the new country. While other studies have found that trust among migrants adapts to destination country trust levels, we find that after the (approximate) age of 30, high trust is a sticky personality trait. The results are robust to controlling for a large array of individual characteristics (including age) and support the view that social trust is sensitive to events that occur early in life.