Multilevel classes are diverse classes in which learners from different backgrounds, life experiences and language skills are placed together in one group. The multilevel approach in English as a Foreign Language (EFL) contexts is becoming more common around the world due to various reasons: funding constraints, learner scheduling difficulties, increased number of learners (Ashton 2018), and program logistics (Shank, 1995). Through previous research on teachers’ experiences (Ashton, 2018), it is known that the multilevel method offers both challenges and benefits to adult English learning. As challenges, there are beginners’ vulnerabilities, insecurities, and demotivation throughout the learning process, naturally segregating themselves from others (Mathews-Aydinli & Horne, 2006). Additionally, advanced English learners, who have more knowledge and language skills than classmates with lower proficiency, may potentially be frustrated at sitting through instructions geared towards much lower levels. As benefits, advanced students potentially provide assistance through meaningful interactions with beginners. However, due to the lack of research on learners’ experiences and views of multilevel English classes, it is crucial to explore and listen to learners’ own experiences as English learners. The purpose of this qualitative case study is to explore adult Brazilian English learners’ views and experiences of multilevel English as a Foreign Language (EFL) classes, particularly, beginners and advanced students studying at a specific multilevel English institute located in Brazil. Data collection included ten individual interviews and 4.5 hours of classroom observations. This study found similar and different experiences among English learners in multilevel EFL classes, such as: both groups believed that the biggest challenges of the multilevel is to have pre-class preparation and to interact positively with each other despite their different levels of proficiency. The results are relevant for teachers-facilitators, students, and those managing multilevel EFL institutes in Brazil, bringing different perspectives towards the multilevel EFL classes. The findings will ideally lead to the schools developing more effective tools for further professional development on multilevel EFL teaching, teacher education programs.