This study aims to assess the effects of pre‐adult international experiences on expatriate workers' cultural intelligence (CQ). Two data sources were used to achieve this goal; a quantitative survey administered online to expatriates (n = 1713) and the culture database of Hofstede. The analyses identified six deep antecedents of CQ. This study contributes to the scientific literature on the antecedents of CQ by examining non‐work‐related international experiences before adulthood in two cultural contexts. It is also one of the first studies to use the third culture kids concept to explain expatriate CQ.