Research on teacher strategies to improve learners' willingness to communicate (WTC) is limited. However, encouraging outside-the-class conversations could increase L2 exposure and improve communicative skills. This study investigated the effects of self-assessment of self-recorded conversations on Thai university EFL learners' WTC and self-perceived communicative confidence. It also explored their attitudes towards the self-assessment. A mixed-method research design involving questionnaires, reflective reports, and interviews was employed to gain a comprehensive understanding of the effects and perspectives among 46 first-year university students with low English proficiency. Six students were interviewed to provide deeper insights into self-assessment effects. The results suggested that the self-assessment could develop WTC and self-perceived confidence. Also, it could raise awareness of their speaking problems as well as promote learning autonomy and the feeling of being supported by the teacher. Teachers can use the findings to increase learners' WTC and foster learning autonomy, especially in the EFL context.