This study estimates the cost of the crisis in Syria derived from the loss of human capital formation. It does so by assigning monetary value to the reduction of lifetime earnings derived from children dropping out of school. Differences in lifetime earnings are calculated based on the observed differences in wages for people with different levels of academic attainment in pre-conflict Syria, adjusted using a discount rate. This difference is then applied to the number of children of primary and secondary age estimated to be out of school in Syria as of the 2012/13 school year. From this, the estimated cost of the loss of human capital formation due to the ongoing crisis in Syria is estimated to be US$10.7 billion, or about 17.7 per cent of the Syrian gross domestic product (GDP) in 2010. This estimation emphasizes the importance of providing access to education to children affected by conflicts, both during conflicts and after such conflicts end.