AbstractLittle is known about what factors predict the formation of reciprocal same‐sex friendships during early adolescence. To examine whether social‐emotional competencies aid in establishing and maintaining these friendships at the beginning and end of seventh grade, 380 German youth (mean age = 12.6 years; 49 percent boys; 100 percent White) reported on their peer support networks and on three broad categories of social‐emotional competencies (i.e., non‐constructive anger regulation, constructive anger regulation, emotional awareness, and expression disclosure). Regression analyses indicated the number of reciprocal friendships at Time 2 (T2) was predicted by adolescents' constructive anger regulation through redirection of attention, and social support when angry at the friend, even after controlling for Time 1 number of friends and peer acceptance. Among girls, willingness to self‐disclose marginally predicted their number of reciprocal friends at T2. Results are discussed in terms of the specific social‐emotional competencies that facilitate involvement in reciprocal friendships.