The social integration of adolescents of foreign origin is of much importance to contemporary Swedish politics, and knowledge is needed about the associations between different forms of leisure and social integration. The present study tests the associations between visits to youth centers and participation in structured leisure activities, on the one hand, and having friends regardless of origin, of native origin, and of foreign origin, on the other. Two-wave longitudinal data from 203 adolescents of foreign origin were collected, including friendship nominations from 1,185 peers. Cross-lagged panel models were constructed, controlling for relevant confounders. Visits to youth centers positively predicted the number of friends of foreign origin, while participation in structured leisure activities positively predicted the number of friends regardless of origin. In conclusion, structured leisure activities appear better than youth centers for promoting the social integration of adolescents of foreign origin into networks of friends of different origins.