BACKGROUND: School-based meal programs can promote healthy dietary intake in youth. However, limited data exist regarding the impact of income-targeted school meal programs across countries, particularly among food-insecure youth. OBJECTIVES: We examined self-reported awareness of and participation in free school meal programs, and associations with dietary intake in youth from 6 countries with differing national school meal policies. METHODS: Data were collected through the 2019 International Food Policy Study Youth Survey, a cross-sectional survey of 10,565 youth aged 10-17 y from Australia, Canada, Chile, Mexico, the United Kingdom, and the United States. Regression models examined: 1) country differences in awareness of and participation in breakfast and lunch programs; and 2) associations between lunch program participation and intake of fruit and vegetables, and "less healthy" foods during the previous school lunch day. RESULTS: Awareness of and participation in free breakfast and lunch programs varied across countries. Approximately half of USA and Chilean students participated in school lunch programs-the countries with the most comprehensive national policies-compared with one-fifth of students in the United Kingdom, and ∼5% in Australia, Canada, and Mexico (P < 0.001 for all contrasts). In the United States and Chile, more than two-thirds of youth with the highest level of food insecurity participated in lunch programs, compared with 45% in the United Kingdom, 27% in Canada, and ≤20% in Australia and Mexico. In all countries, youth reporting school lunch program participation were more likely to report fruit and vegetable intake during their previous school lunch (P < 0.001), and higher intake of "less healthy" food in all countries except the United States and Chile. CONCLUSIONS: More comprehensive national policies were associated with greater participation in school meal programs, particularly among youth at greatest risk of food insecurity, as well as healthier dietary intake from school lunches.