In multicultural learning environments, instructional designers face an important question: should they adopt universal frameworks that address general learner variability, or culturally grounded frameworks that address learners’ cultural contexts? This conceptual paper compares Universal Design for Learning (UDL) with a culturally grounded instructional-design model to examine points of alignment, divergence, and applicability across diverse educational settings. Both frameworks emphasize inclusive, flexible design through engagement, representation, and learner agency (CAST, 2018). However, they differ in epistemological orientation and in their use of culture. For instance, UDL addresses learner variability of affective, cognitive, and metacognitive dimensions, which can help to build a scalable foundation for learner accessibility. In contrast, a culturally grounded model, drawing on sociocultural theory and culturally responsive pedagogy, positions culture as central, situating variability within learners’ home cultures, institutional contexts, and emergent classroom cultures (Gay, 2018; Vygotsky, 1978). We propose a structured approach to aid instructional designers in selecting the most appropriate instructional design model under certain conditions. For example, we argue that UDL is most effective when accessibility and scalability are the most important priorities, whereas a culturally grounded model should be used when instruction must navigate multiple cultural systems, foster relational trust, and support co-construction of meaning. By aligning framework selection with the cultural complexity and instructional goals of the learning environment, designers can create learning experiences that address learner needs.