The societal gains from increased physical activity among children are substantial. This study aims to contribute with knowledge about how the benefits of increased physical activity are valued by the Swedish general public. The methodological approach is a contingent valuation survey (n = 768), which allows to capture values associated with increased physical activity that extend beyond the health domain. To our knowledge, this is the first study using a contingent valuation approach to assess the comprehensive benefits of promoting physical activity. Although almost all respondents support the idea to promote active school transport in general, slightly more than half the sample reject the idea to contribute financially, while almost half the sample state a positive willingness to pay (WTP), and only approximately 10% state a positive WTP without uncertainty. The average WTP a lump sum for the intervention is estimated to lie between SEK64-185 (approximately 6–19 Euros). Higher WTP correlates with income, perceptions that lack of physical activity as a serious problem, and regular exercise engagement. Due to limited access to cost data, a full economic evaluation is not possible. Nevertheless, even using lower-bound WTP (uncertain = 0), aggregate benefits exceed teacher‐time costs, which are expected to constitute the most important part of intervention costs. Policymakers are recommended to implement low-cost interventions to increase physical activity of children, for instance by promoting the use of active school transport.