The aim of this study was to establish whether children treated with subtalar arthroereisis for flexible flatfoot were able to return to sport activities. We reviewed 49 patients with a mean age at the time of surgery of 10.7 years. The type of sport activities, the number of sessions per week, the time dedicated to each session, and the level achieved were assessed preoperatively and at the last follow-up. Overall, 45 patients returned to sports after surgery. Surgery did not alter the duration, frequency, and type of sporting activities, but the participation in physical activities as well as the emotional status and footwear issues improved.