Washback refers to the influence of a test on teaching and learning. This study was an attempt to compare the influence of IELTS and TOEFL iBT on the expectations the students brought to their courses and to investigate how these expectations were fulfilled. To this end, 100 IELTS and 120 TOEFL iBT students attending preparation courses took a questionnaire survey, and a sample of their ten classes was observed as a part of validation process of triangulation research. The data gathered were subjected to quantitative and qualitative analyses. The results of the study indicated that the IELTS students’ expectations of the courses were higher than those of the TOEFL iBT students. On the other hand, both the IELTS and the TOEFL iBT students had higher expectations of the courses than what they had during their class activities; however, the IELTS students’ expectations were fulfilled to a greater extent. The study also concluded that the students of both IELTS and TOEFL iBT adjusted their expectations mostly to accommodate to the demands made by test tasks. Generally, the class activities and the expectations of both groups were more influenced by negative washback of the tests. However, IELTS seemed to promote more positive washback on students’ expectations and class activities.