The efficacy of Trauma-Focused Cognitive Behavioral Therapy (TF-CBT) in treating child traumatic stress inspires nationwide dissemination, yet widespread adoption by state systems of care is lagging. A significant barrier is the cost of implementation and maintenance of evidence-based services. Thus, the current study examined the annual costs of mental health services accrued for 90 publiclyinsured, trauma-exposed children from the time they began participation in a TF-CBT implementation project to 1 year after their admission. These costs were compared to those accrued over that same time period by 90 trauma-exposed control children that were matched by demographics and prior mental health services utilization using a propensity score matching algorithm and provided outpatient treatment as usual. Results indicated that (a) 27.5 % of the total cost was attributed to high-end services utilized by only 1.67 % of children; (b) two times more money was spent on low-end mental health services received by the TF-CBT group than the control group, and (c) five times more money was spent on high-end mental health services received by the control group than the TF-CBT group in that year. These data suggest that providing evidence-based trauma-focused outpatient treatment to children with trauma-related problems may offset the eventual need for services that are more restrictive and costly.