Background: Active commuting to school (ACS) can be an important source of physical activity for children. Schools are an important setting for policy-related ACS promotion. The purpose of this study was to examine the association between school policies and ACS, and to assess whether this relation varied by grade. Methods: This cross-sectional study used data from schools recruited to the Safe Travel Environment Evaluation in Texas School study (n = 94). The percent of trips made by active travel modes was measured through tallies among third to fifth grade classrooms from 5 school districts in Central Texas in 2018–2019. School ACS policies and practices were measured through 8 survey items aggregated into a score. Linear mixed effects models were used to assess the association between policies and ACS. Results: School health policy surveys and ACS data were collected from 69 elementary schools. An average of 14.6% of trips to/from school was made using active travel modes. Schools with higher numbers of policies had significantly higher percentages of students using active travel modes (P = .03), and for each additional policy, the predicted percentage of trips made by active travel modes was 1.46% higher. There was a significant interaction effect between school policy and grade, with stronger correlations among higher grades (P = .002). Conclusions: Results from this study demonstrate a correlation between the school policies designed to support walking and biking and ACS. Results from this study can be used to justify the use of school-based policy interventions to promote ACS.