Critical thinking (CT) is increasingly recognised as essential in English as a Foreign Language (EFL) education for enhancing both language proficiency and cognitive skills. This study explores how sociocultural contexts shape EFL teachers' beliefs and instructional practices regarding CT in T & uuml;rkiye and Vietnam. Using a qualitative approach, semi-structured interviews were conducted with 25 EFL teachers to examine how cultural, educational, and institutional factors influence CT instruction. The findings reveal distinct pedagogical orientations: Vietnamese teachers favour implicit methods aligned with collectivist traditions and hierarchical classroom dynamics, whereas Turkish teachers adopt more explicit instructional strategies influenced by recent educational reforms promoting inquiry-based learning. Despite these differences, both groups face common challenges, including a growing reliance on AI tools that may undermine critical thinking, resource limitations, and exam-focused curricula that prioritise rote learning over analytical skills. The study underscores the need for culturally responsive pedagogical strategies and targeted teacher training to better integrate CT into EFL instruction. These insights contribute to the global discourse on CT in language education and offer valuable recommendations for educators, curriculum developers, and policymakers seeking to foster critical thinking in diverse educational settings.