Inclusive education, crucial for human rights and sustainable development, focuses on integrating and empowering students of varying needs and abilities. Understanding the interaction between Universal Design for Learning (UDL) and Differentiated Instruction (DI) is key for educators and stakeholders to implement inclusive strategies effectively. Yet, there is a significant gap in empirical research exploring this relationship. Therefore, this study examined a proposed model combining growth mindset and practice factors (ongoing assessment and flexible grouping), which explained how UDL is related to DI. Structural equation modeling was used to analyze data from 647 in-service teachers. The findings showed that practice factors independently and in combination with a growth mindset fully mediated the relationship between UDL and DI. The implications for the research community, teachers, and teacher educators to implement UDL and DI are presented.