The present study investigates the effects of collaborative output tasks on the learning of L2 phrasal verbs (PVs). For this study, seventy-two Korean university students were divided into two groups: pair (P) and individual (I). Each group was asked to learn 16 PVs either in a cloze (C) or an editing (E) condition. The students had four learning sessions over a period of six weeks. The learning effects and retention were measured through receptive and productive tests in two posttests. The findings revealed that the P group consistently outperformed the I group, but significant differences were found only in the delayed posttests. The findings also showed that the students performed better in the C condition than in the E condition, and the differences were significant in the two posttests. The retention rates in the P were higher than in the I group. The retention rates in the E were higher than in the C condition. These findings support the superior effects of collaborative output tasks in L2 PVs learning.