Abstract Introduction Covid-19 pandemic may have had negative effects on overweight and overweight-related health behavior in young adults. The aim was to examine the changes in overweight, physical activity, sedentary behavior and daytime tiredness in higher education students during and after the pandemic. Methods Two cross-sectional student representative surveys (aged 18-34 y) were conducted in 2021 (n = 6258, response rate 53 %) and 2024 (n = 3638, response rate 31 %). Overweight (BMI ≥25 kg/m2) was based on self-reported height and weight. Physical activity was dichotomized into those meeting physical activity recommendations and others. Sedentary behavior was dichotomized into sitting in front of TV, computer or smart device over three hours a day during leisure time and others. Daytime tiredness was dichotomized into those feeling tired 6-7 days a week and others. Results The preliminary results indicate that overweight in women increased from 34 % to 39 % whereas no increase was observed among men (47 % vs. 46 %) between 2021 and 2024. Meeting the physical activity recommendation increased from 46 % to 55 %, the change being similar for both sexes. Sitting over three hours in leisure time in front of TV, computer or smart device decreased from 54 % to 50 %. In men, the prevalence of sitting decreased (62% vs. 57 %) whereas in women no statistically significant change was observed (47% vs 45 %). No statistically significant change was observed in feeling tired almost every day (26 % vs 24 %). Conclusions Among higher education students, an increase in prevalence of overweight in women was observed for three years period. Favourable changes were observed in physical activity in both men and women, and sedentary behavior in men. Surveillance of the long-term health consequences of the pandemic in young adults is important for planning and targeting preventive activities. Key messages • Overweight increased among female higher education students after COVID-19 pandemic. • Factors supporting favourable changes in health behaviour of young adults after pandemic should be examined in longitudinal setting.