Research on washback, . test impacts on teaching and learning in class, of high-stake English tests is prevalent. Little attention has, however, been paid to washback of an English achievement test (EAT) albeit its highly practical significance including reporting and improving teacher effectiveness right in a programme in a specific context (El-Kafafi, 2012; Antineskul & Sheveleva, 2015). The present paper aims to explore teachers’ perceptions of the teaching contents under the influence of an EAT which steps up to an English Proficiency Test - PET (or B1 level equivalent) for university undergraduates in Vietnam as required for graduation by Vietnam’s Ministry of Education and Training (MOET). The EAT, mirroring the PET, was designed to expect positive washback in the course English 2. | Washback of an English achievement test on teachers perceptions at a Vietnamese university