Despite the surge of interest in evaluating culture representation in English language teaching (ELT) materials, the literature has not adequately addressed representations of culture in English for Academic Purposes (EAP) textbooks. To bridge this gap, the present study draws on the Cultural Linguistics semiotic approach to evaluate texts, tasks, and visuals in three locally-developed EAP textbooks in Iran. To this end, we triangulated interview data and narratives obtained from the materials developers of the selected textbooks and a local EAP policymaker with the analysis of texts, tasks, and images. The findings revealed that: (a) few instances of cultural schema and cultural categories were found in the textbooks; (b) mostly materials developers either were not cognizant of the notion of cultural conceptualisations when designing the textbooks or they did not consider it a significant priority in EAP textbooks due to some politico-religious reasons; (c) metacultural development tasks were barely presented in the pre-, while-, and post-reading tasks; and (d) an incompatibility prevailed among texts, tasks, and visuals regarding the presented cultural conceptualisations. The findings are discussed with reference to the need to raise EAP materials development stakeholders’ awareness about the effectiveness of cultural conceptualisations and metacultural competence in EAP education.