Little information is available regarding the financial and non-financial costs of implementing and sustaining universal trauma and mental health screening in state child welfare systems. A cost analysis was conducted as part of a 5-year, federally funded statewide demonstration project to install universal trauma screening in one state’s child welfare system. The project implemented a battery of validated instruments that varied by age of the child (0–18) to measure trauma exposure, post-traumatic symptoms and child well-being. All adjudicated children and youth involved in the state child welfare system are targeted for initial screening within the first 60 days, and then every subsequent 6 months while in care. The cost of administering the screening tool and related post-screening activities was estimated to be $74 per screen in 2016 dollars. Overall, implementation and maintenance costs were estimated at $1213/trained caseworker, including both direct and indirect costs. Costs to sustain screening activity past the grant period were also calculated. While the grant funding provided more dedicated resources than states may typically have for implementing a new screening initiative, most of the cost-related screening processes reported here, such as planning (e.g., choosing measures, determining workflow) and implementation (workforce training, programming a web-based interface) would be necessary for any state or territory wanting to install universal screening. With growing interest in trauma-informed screening and prevention in child welfare, it is critical to understand and determine the financial costs of screening.