Evidence about social costs of gambling is scarce and the methodology for their calculation has been a subject to strong criticism. We aimed to estimate social costs of gambling in the Czech Republic 2012. This retrospective, prevalence based cost of illness study builds on the revised methodology of Australian Productivity Commission. Social costs of gambling were estimated by combining epidemiological and economic data. Prevalence data on negative consequences of gambling were taken from existing national epidemiological studies. Economic data were taken from various national and international sources. Consequences of problem and pathological gambling only were taken into account. In 2012, the social costs of gambling in the Czech Republic were estimated to range between 541,619 and 619,608 thousands EUR. While personal and family costs accounted for 63% of all social costs, direct medical costs were estimated to range from 0.25 to 0.28% of all social costs only. This is the first study which estimates social costs of gambling in any of the Central and East European countries. It builds upon the solid evidence about prevalence of gambling related problems in the Czech Republic and satisfactorily reliable economic data. However, there is a number of limitations stemming from assumptions that were made, which suggest that the methodology for the calculation of the social costs of gambling needs further development.