Bridging the Formal and Informal Learning Divide: How Institutional Support Shapes Informal Digital Learning of English in Thailand

Abstract Despite the documented merits of Informal Digital Learning of English (IDLE), a critical gap persists in understanding how learner‐external factors drive students' proactive learning behavior, particularly within under‐explored Global South contexts. This explanatory mixed‐methods study examines how multilayered institutional supports, including pedagogical quality, university policy, institutional resources, and the campus language environment, predict Thai university learners' IDLE practices. Regression and relative importance analyses ( N = 749) showed that the final model explained 58% of the variance in IDLE. The Lindeman–Merenda–Gold analysis attributed broadly comparable shares of the explained variance to institutional resources (26.0%), pedagogical quality (25.2%), the language environment (24.4%), and university policy (24.4%). Semi‐structured interviews ( N = 12) complemented the quantitative findings and further illuminating the role of learner agency and digital awareness in translating institutional supports into autonomous digital learning practices. Ultimately, the findings demonstrate that IDLE is not merely an isolated individual endeavor but is deeply intertwined with formal institutional ecosystems that foster autonomous digital learning beyond the classroom. This study finally offers potential attempts for integrating formal instruction with IDLE practices in Thailand higher education.