Participants were 109 American college students studying Chinese in a study-abroad programme in Beijing. Following Kelley and Meyer, intercultural competence was defined as cross-cultural adaptability involving four dimensions (emotional resilience, flexibility/openness, perceptual acuity and personal autonomy) and was measured with a survey. A language contact questionnaire was used to document the amount of time spent on social activities. Language proficiency was measured with a standardised Chinese test. Results revealed that intercultural competence and language contact combined explained 37.7% of the proficiency gains. Language contact had direct effects on proficiency, but intercultural competence had indirect effects, mediated by language contact.