The aims of this study were to assess the mediating role of household socioeconomic position (SEP) in the associations between the country-level factors: family social benefits, and public income support to single parent households (SPH), with the individual-level factor adolescent life satisfaction. Our sample consisted of adolescent (11, 13, and 15 years old) participants in the Health Behaviour in School-aged Children study (2013/2014) across Canada and 24 countries in Europe. We used World Bank data on country wealth from OECD data on social benefits for families and public income support to SPH. Multilevel linear regressions assessed mediated (indirect) associations of these country-level predictors, through SEP, with life satisfaction. Family social benefits ranged between 1.1% and 3.7% of country wealth. The direct association showed that family social benefits were associated with lower adolescent life satisfaction (β = -0.244, 95% Confidence Intervals [C.I.] = -0.306, -0.182, p < 0.0001) among all adolescents and for adolescents in SPH (β = -0.118, 95% C.I. = -0.161, -0.074, p < 0.0001). However, the mediated (indirect) association showed that family social benefits were associated with higher life satisfaction which is partially mediated by SEP (β = 0.087, 95% C.I. = 0.065, 0.109, p < 0.0001) among all adolescents and for adolescents in SPH as well (β = 0.041, 95% C.I. = 0.030, 0.052, p < 0.0001). Country policies may support the wellbeing of adolescents by reducing poverty and improving their socioeconomic position in society.