Fraud incidence in healthcare is not easy to find. As a country that only started Social Health insurance (JKN program) since 2014, there are not many parties that provide fraud detection tools for INA CBG case-mix system. In addition, the law that establishes an investigation for potentially fraudulent incidents is still being drafted. On the other hand, there is a significant increase in the JKN’s participants & in the number of claims. By the end of 2017, the number of claims submissions were 80,641,271 cases. The situation encouraged BPJS Health Indonesia to develop DEFRADA, a fraud detection tool for INA-CBG claim of referral health services. This paper outlines the implementation of Defrada and its achievement in cost efficiency for JKN. In 2017, Defrada has contributed for cost efficiency about 25-30 per cent of the total efficiency gain. This implementation has shown efficiency from data analysis are offer room for improvement in the future.