Informal settlements constitute a prominent form of urbanization across the world. The rapid growth of Yazd presents an example of informal urbanization in Iran at the nexus of development, poverty, and inequality. While scholarship on urban informality is abundant, a lacuna exists in the literature on systematic quantitative research on informality among urban residents. The present study investigates residents' perceptions regarding informality and captures their responses before and after the expansion of an informal settlement in Yazd. Through this quantitative research, we aim to articulate and highlight specific domains of informality, offering a framework assessing the complexities of informality that extend beyond only Iranian informal settlements. This paper analyzes the status of urban informality and migration in terms of their social, economic, physical, environmental, and urban management characteristics in “Airport Neighborhood”, a prominent Yazd neighborhood. This paper seeks to add theoretical and empirical depth to the categorization of distinct yet overlapping domains of informality. Our quantitative approach to migration and informality informs our central research question: How does the complexity of informality affect different groups of people living in one informal settlement? We find that recent migrants to the settlement are less involved in urban governance, women experience improved work opportunities after moving to the informal settlement but remain marginalized, and insufficient and poorly maintained infrastructure operates as a significant barrier to socio-economic stability and mobility. We also find that urban settlement results in increased debt among residents in Airport Neighborhood, and that youth unemployment is a significant issue that did not improve for recent migrants to the neighborhood despite young people citing employment as a key motivating factor for migration. Our empirical work highlights the theoretical complexity of informality, as subgroups of people face varying challenges that correlate with their age, gender, and time spent in a particular informal settlement.