This multisite study replicates Webb, Newton, and Chang's (2013) study on the effect of repetition on incidental learning of multiword units (MWUs). Even though more researchers have started to investigate MWUs, most data have been collected from university students. Furthermore, the large effect of MWU repetition on learning reported by Webb et al. has not yet been corroborated. Data in our study were collected from two university samples (EFL students in Poland and Flanders) and one nonuniversity sample (Flemish EFL learners in secondary schools). Unlike Webb et al., we adopted a counterbalanced within-participants design. Participants read and listened to a modified graded reader in which target MWUs occurred 1, 5, 10, or 15 times. In line with the initial study, we found a positive effect of repetition. However, the learning gains were smaller, and the number of repetitions needed was different. The findings were consistent across the university and nonuniversity samples. The study concludes with a discussion of these findings in relation to both pedagogical implications and the benefits of multisite replication research.