Amidst a background of inequality and rising global tensions, the need for effective intercultural understanding is paramount, facilitated by well-prepared teachers. Small-scale, qualitative studies indicate potential positive effects of scaffolded study abroad during initial teacher education on teaching in increasingly diverse classrooms. The study utilizes large scale data from teachers to explore teacher self-efficacy in multicultural classrooms and the inter-relationship with study abroad during teacher education. Survey data from teachers in England and Australia is sourced from Teaching and Learning International Survey (TALIS) 2018, as well as a small-scale survey from Australian Capital Territory (ACT). These teachers reported a lack of preparedness for teaching in multicultural classrooms from teacher education. Findings from hierarchical regression analysis suggest that study abroad during teacher education is significant in improving teacher self-efficacy, after controlling for significant variables related to teaching in a multicultural classroom. We argue for the inclusion of study abroad in initial teacher education for much needed intercultural understanding.