ObjectivesThis study investigated the costs of 2-hour multiprofessional in situ hospital trauma team simulation training and its effects on teams’ non-technical skills using the T-NOTECHS instrument.BackgroundSimulation is a feasible and effective teaching and learning method. Calculating the costs of simulated trauma team training in medical emergency situations can yield valuable information for improving its overall cost-effectiveness.DesignA prospective cohort study.SettingTrauma resuscitation room in Central Finland Hospital, Finland.Participants475 medical professionals in 81 consecutive, simulated trauma teams.Primary and secondary outcome measuresTeam simulation training costs in 2017 and 2018 were analysed in the following two phases: (1) start-up costs and (2) costs of education. Primary outcome measures were training costs per participant and training costs per team. Secondary outcome measures were non-technical skills, which were measured on a 5–25-point scale using the T-NOTECHS instrument.ResultsThe annual mean total costs of trauma team simulation training were €58 000 for 40 training sessions and 238 professionals. Mean cost per participant was €203. Mean cost per team was €1220. The annual costs of simulation training markedly decreased when at least 70–80 teams participated in the training. Mean change in T-NOTECHS score after simulation training was +2.86 points (95% CI 1.97 to 3.75;+14.5%).ConclusionsThe greater the number of teams trained per year, the lower the costs per trauma team. In this study, we developed an activity-based costing method to calculate the costs of trauma team simulation training to help stakeholders make decisions about whether to initiate or increase existing trauma team simulation training or to obtain these services elsewhere.