Studying abroad is considered one of the most efficient ways to accumulate ‘transnational human capital,’ i.e. foreign language skills and intercultural competencies. Focusing on Japan, this paper investigates socioeconomic inequality in study abroad intent (SAI) and pre-college study abroad (PSA) participation. Drawing on sociological rational choice theory, the differences in SAI and PSA by socioeconomic status (SES) of the families are explained as a result of family decision-making based on status maintenance motives. Using data from the 2nd Survey on Extra-curricular Activities, 2013 (N = 15,450) for children aged three to eighteen years, binary and generalized ordered logit regressions confirm a significant impact of parental SES (income and education) on SAI and PSA likelihood (long- and short-term) for children at all levels of schooling. Applying the KHB method, we also examine the degree to which PSA mediates the effect of SES on SAI. Findings suggest that children from high SES families are generally more likely to study abroad and consider long-term stays more often, indicating undetected first- and second-level horizontal inequalities.