Erasmus+ experiences are shown to impact students' beliefs and values, offering exposure to English in daily life. This qualitative exploratory case study investigates how Erasmus+ mobility affects Turkish English as a foreign language (EFL) high school students' conceptualization of English learning and use in other EFL contexts in Europe between 2020 and 2022 by encompassing the English as a lingua franca (ELF) perspective. The theoretical framework in the study is sociocultural theory. The data, collected via semi-structured interviews and reflective journals, were analyzed via grounded theory. The findings revealed that three students out of four favored ELF with the emerging themes of criticality, intercultural awareness and competence, glocalization, and communicative competence, while one student persisted in keeping the normative EFL mindset. Pedagogical implications are discussed in the light of Erasmus+ mobilities and ELF intersection.