In Thailand, learner autonomy has been introduced to enable students to manage their learning and engage with the abundant resources available, particularly for English language learning. This study examines the extent of learner autonomy and online language learning behaviors outside the classroom among Thai university students, as well as the factors influencing their autonomy. Quantitative data was collected through a questionnaire from 378 freshmen representing eight faculties: Allied Health Sciences, Medical Science, Public Health, Sciences, Agriculture, Law, Business, and Humanities. The findings revealed a relatively high level of learner autonomy among Thai university students. They were able to establish learning goals, select learning strategies and resources, and be aware of their weaknesses. However, the overall level of online language learning outside the classroom was moderate. Listening to English music was the most popular activity reported. Additionally, gender and English proficiency were identified as significant factors influencing the level of learner autonomy. These findings underscore the effectiveness of introducing learner autonomy but also highlight the need for teacher support in scaffolding online language learning outside the classroom.