Unusually high levels of Cluster B and C personality traits have been observed in schizophrenia. While these have been linked to poorer function, less clear is the association of these personality traits with symptoms and service utilization. To examine this issue, 46 participants with schizophrenia or schizoaffective disorder were administered the Millon Clinical Multiaxial Inventory, Third Edition, and the Positive and Negative Syndrome Scale, and an inventory was taken of medical and psychiatric service utilization. Two sets of multiple regression analyses using Cluster B and C traits to predict treatment utilization and symptoms revealed that emotional discomfort symptoms were significantly related to level of borderline traits. Higher levels of positive symptoms were linked with more avoidant traits and fewer dependent traits. Higher levels of negative symptoms were linked with greater avoidant traits. Service utilization was predicted by borderline, antisocial, and avoidant traits. Implications for rehabilitation and treatment are discussed.