Are depressive symptoms associated with more biased or more accurate interpersonal perceptions? Both members of committed heterosexual couples (N = 78) reported on their perceptions of their partner’s commitment and behavior daily across a 3-week period. Using the partner’s reports as the benchmark, participants who reported more depressive symptoms not only underestimated their partner’s commitment and overestimated their partner’s negative behavior (greater directional bias) but were also more accurate in tracking changes in their partner’s commitment and behavior across days (greater tracking accuracy). More negative perceptions of the partner’s commitment and behavior was also associated with increases in relationship insecurity and depressed mood, particularly when the partner also reported lower commitment and more negative behavior. These results indicate that depressive symptoms are associated with both more accurate and more biased interpersonal perceptions and suggest that more accurate detection and more biased magnification of interpersonal threat has important implications for the maintenance of depressed mood.