In light of contemporary pedagogical methods, the flipped classroom has been recognised as an effective pedagogy in English as a Foreign Language (EFL). This study employed a quasi-experimental one-group research design to investigate the impact of flipped learning on Omani EFL learners' grammar and to examine students' perceptions on the flipped classroom. An intact group of students (n=28) enrolled at the foundation programme in Arab Open University-Oman was randomly selected. Seven videos on English grammar were developed and shared with the students prior to the class. A varaiety of activities were conducted in the class following task-based language teaching. Students met for 8 lessons over the period of 8 weeks. Pre-test, post-test and semi-structured interviews were used in the study. The findings indicated that flipped learning had a positive impact on students' understanding and usage of English grammar. Students' perceptions on the flipped approach were positive. The study also provided pedagogical insights for the flipped classroom and recommendations for future research.