Newly built environments in cities whose features have changed due to neoliberal policies and priorities have often been criticized for their lack of aesthetic qualities. This criticism has made the aesthetic assessment of such environments more important, raising two crucial questions: how such an assessment can be performed, and how it can be incorporated into legislation. This article focuses on both questions in the case of Istanbul by determining and ranking formal aesthetic factors using factor and ANOVA analyses of the results of a survey conducted with three different sampling groups (scholars, designers, and officials) in Istanbul in 2017. The results of the analyses show that scholars' views in evaluating urban formal aesthetics are different from those of officials and designers. In addition, the analyses reveal that "character and identity", "green design", and "incompatibility between identity and design" are three important factors affecting urban formal aesthetics in newly built environments. These results are then followed by a discussion on how these factors can be incorporated into legislation in the case of Istanbul.