In many European countries, immigrants tend to view vocational education and training (VET) programs as less desirable for themselves and their children. Students with migration background, therefore, show stronger preferences for academic education over VET programs. This article contributes to the literature on immigrants' educational choices by investigating whether their educational preferences change as foreign-born students live in Switzerland for longer periods. Using data of the Programme for International Student Assessment (PISA) of ninth-grade students between 2000 and 2012, our results confirm that the probability to prefer a VET program, conditional on cognitive ability, increases for foreign-born students the longer they have been in Switzerland. By exploiting variation in students' knowledge level at the time of immigration, we provide a tentative test for whether differences in the level of knowledge on the host country's education system influence immigrants' educational choices. For students born in a country with a similar VET system and for students with a parent born in Switzerland, the preference for VET programs did not increase with the time spent in Switzerland. These findings suggest that a lack of information about the Swiss education system biases immigrants' educational preferences and this bias can lead to suboptimal choices. Thus, policymakers should ensure that immigrant students early receive information about the host country's education system.