This report summarizes an investigation of literature published in 1985-2023 on universal design (UD) of large-scale assessments. State education agencies, K-12 assessment vendors, teacher trainers, and classroom teachers are increasingly applying the principles of UD to the instruction and assessment of students from special populations. In theory, UD ensures that instruction and assessment are created from the beginning to be accessible to the widest population of students possible. Yet, it is unclear how these UD frameworks and their associated principles and elements are being applied, or even which UD framework is used. This obscurity and lack of defined UD principles in the research literature creates obstacles in research replication and in identification of evidence-based practices. This scoping review identifies how the concept of UD has been applied to the broad range of U.S. district and state large-scale academic assessments. We included literature on the application of UD to the broad range of K-12 district and state large-scale academic assessments in the U.S.