Political trust among immigrants in Western Europe seems to be surprisingly high, especially among immigrants from non-democratic countries with institutions plagued by corruption. Over time, however, trust tends to diminish among these individuals. In this paper we argue that this may neither be explained by acculturation nor by experiences of discrimination. Analysing Swedish survey data we instead conclude, although tentatively, that falling expectations regarding the performance of host country institutions is a fruitful explanation. Such expectations presumably become more modest the longer one has been living in Sweden, causing a time-related drop in the overall confidence in Swedish political institutions.