Mental health interventions, such as Youth Readiness Intervention (YRI), offer an opportunity for improving the mental health of war-affected youth in fragile and conflict-affected regions. The YRI has demonstrated effectiveness in improving mental health outcomes, yet prior analyses have not examined the economic impact of the YRI integrated within with an entrepreneurship (ENTR) program. A costing analysis was conducted using standard activity-based costing methodology to estimate implementation costs. Next, economic benefits (productivity, healthcare offsets and local returns) were estimated, using participant-reported and secondary data. Total benefits were compared with total costs to calculate the return on investment (ROI), taking into consideration varying unemployment rates as a result of the intervention. Results show that the YRI + ENTR implementation cost is $117,289.00 ($305.44 per participant) and the ENTR-alone implementation is $67,279.10 ($177.05 per participant). The ROI for the YRI + ENTR varies from $1.01 to $1.95. The ROI for the ENTR alone varies from $2.53 to $6.92. In one of the ROI pathways – that is, healthcare savings – we find that the YRI + ENTR results in an 8.5-fold larger healthcare saving compared to the ENTR alone. This is one of the first studies to examine the broader economic returns of the YRI and ENTR program and are important to consider in future implementation due to the broad nature of economic benefits.