The COVID-19 pandemic globally had worrisome effects on health-promoting behaviors of children. Currently, the impact on primary school children's membership in sports clubs, especially considering gender differences, is poorly studied. The main objective of this study was to analyze the status of sports club memberships among children in Austria after the stringent COVID-19 restrictions in June 2021 and to identify gender differences. 755 Austrian school children (mean age 9.9 years, 49.9% girls) were interviewed about their sports club memberships. Our results show significantly lower self-reported sports club membership in June 2021 compared to pre-pandemic studies. 50% of boys reported being a member of a sports club, while the percentage for girls was only at 29.7% (p<0.001). Besides, a significant gender difference in the type of sports club membership was observed with most boys being members of ball sports clubs, while girls were more likely to be members of other sports clubs (p<0.001). Reduced rates of sports club membership after the COVID-19 pandemic underline the need of intervention programs. Health authorities, schools, sports clubs and families should form an alliance to promote an overall increase of physical activity and thus to support the long-term healthy development of children.