OBJECTIVE Police officers typically face multiple potentially traumatic events and consequently have a higher conditional probability of developing PTSD. Although most police officers with PTSD benefit from first-line treatment, it is unknown whether recommended intensification of treatment for low responders is effective and which factors contribute to response. This study aimed to examine the treatment response of a day clinic for police officers with PTSD and identify predictors of treatment response. METHODS Between 2009 and 2019, routine outcome monitoring measurements consisting of PTSD symptom severity and general psychological distress were administered at two timepoints among 102 patients undergoing a day clinic treatment consisting of trauma-focused therapy, sociotherapy, and psychomotor therapy. Hierarchical regression was used to assess whether change in PTSD symptom severity was associated with baseline PTSD and depression severity, gender, age, and eligibility for a recognition procedure. RESULTS Significant improvements in PTSD symptom severity were found over the course of the treatment (d = .59), with 47% of patients showing statistically reliable improvement in their symptoms. The only significant predictor of treatment response was eligibility for a recognition procedure, with the total model explaining approximately 10% of the variation in treatment response. CONCLUSIONS Intensifying treatment for police officers with PTSD who do not respond to previous trauma-focused treatment appears beneficial for a substantial number of patients. However, eligibility for a recognition procedure may negatively impact treatment response. (PsycInfo Database Record (c) 2023 APA, all rights reserved).