Objectives: Due to globalized migratory processes, female genital mutilation/cutting (FGM/C) has spread to other countries, including countries in Europe, where, with a few exceptions, it remains a concealed problem. To the authors' knowledge, this is the first national extensive study to estimate the prevalence of FGM/C in Portugal. Study design: Prevalence estimation. Methods: Using extrapolation of country-of-origin prevalence data and the 2011 Census data, this study estimated: the prevalence of FGM/C in Portugal among women of reproductive age (15-49 years) and among all women aged >= 15 years; and the number of girls aged <15 years living in Portugal who have undergone or will probably undergo FGM/C. Results: It is estimated that 6576 women aged >= 15 years living in Portugal have undergone FGM/C, with cases distributed unevenly throughout the national territory. In addition, it is estimated that 1830 girls aged <15 years living in Portugal have undergone or are likely to undergo FGM/C. Conclusions: This study estimated that more than 6000 women living in Portugal have undergone FGM/C, and many girls remain at risk. These two groups need different types of interventions. Awareness of the number and geographical dispersion of cases of FGM/C will enable more informed and targeted definition of public health policies for protection of females who have undergone or are at risk of undergoing FGM/C. (C) 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.