This qualitative study investigated the washback of performance-based assessment used by three English language teachers in Hokkaido, Japan, each of whom implemented their own course-specific assessments. The study employed qualitative research of an in-depth interview with 15 students and a self-reflective method from 3 teachers. Teachers demonstrated different approaches in implementing performance-based language assessment. However, they agreed that this type of assessment could enhance students' communicative skills and rubrics were crucial in the assessment process. In terms of washback on students, they found that performance-based assessment, with detailed feedback, provided learners with a comfortable and challenging learning environment, leading to self-developed English performances, feelings of accomplishment, and better retention of English used in the presentations. However, some students found performance-based assessment demanding, causing anxiety. The findings suggest that when implementing performance-based assessment teachers should consider different aspects of the assessment to create positive washback.