Ankle injuries are a common health problem; data on ankle injury rates and time trends in the population at large are scarce. Our aim was to investigate the incidence of and time trends in population-based and emergency department-treated ankle injuries related to sports activities and other activities related to daily living. Data were obtained from one national survey on accidents and injuries (2000-2010) and one based on emergency department data (1986-2010). Linear regression was used to determine linear trends in ankle injuries per 1000 person-years. The number of ankle injuries related to sports activities and other activities of daily living increased from 19.0 to 26.6 per 1000 person-years (P=0.002). The number of sports-related ankle injuries treated in emergency departments decreased from 4.2 to 1.5 per 1000 person-years (P<0.001), and from 3.2 to 2.1 per 1000 person-years (P<0.001) for other activities of daily living. According to our data, the incidence rates of all ankle injuries are around 5.5 times higher than those registered at emergency departments. The high incidence rates of ankle injuries highlight the need for proper ankle injury treatment and prevention.