The incongruity between South Asia’s economic growth and extreme poverty has led to a growing interest in social protection and the subsequent implementation of anti-poverty programs. These work to promote inclusive growth and ensure that the poor do not get left behind. However, many programs have systematically failed to achieve their full potential in reaching the poorest of the poor. We reviewed the literature to understand the determinants behind this inequity in South Asia.A search of four databases, EconLit, Global Health Database, MEDLINE, SocINDEX, supplemented by citation tracking and an external search, yielded 42 papers evaluating 23 social protection programs. All articles were assessed for quality using the GRADE and GRADE CERQual criteria. Data were analyzed using Thomas & Harding’s thematic synthesis approach to generate new higher-order interpretations.Our analysis identified five themes underscoring program processes that stop resources from reaching the poor. These include: (1) structurally flawed program theories that overlook the complexities of poverty and are instead rooted in simplistic cause-and-effect approaches overestimating the poor’s gain from participation; (2) elite capture of program resources through the direct appropriation of benefits, their powerful positioning in program implementation, and their ability to dictate the poor’s accessibility through relationships of patronage and withholding of information; (3) insufficient targeting strategies to reach the poorest and a subsequent redirection of resources toward the rich; (4) program designs that overlook gender-based restrictions, hidden costs, the poor’s lack of legal documentation, and their physical and social exclusion; (5) some of the poorest households actively choosing self-exclusion from social protection due to a desire to maintain dignity, a lack of capital, and a perception of programs as substandard.The review highlights the disconnect between social protection program designs and the ground realities of their ‘ideal’ beneficiaries: the poorest of the poor. We propose the persistence of this well-documented disconnect may stem from three sources. First, there is an unclear understanding of who the poor are in South Asia, with definitions overlooking the historical influence of the caste system. Western perceptions of poverty continue to dominate the discourse. The second challenge is effective engagement and co-production of knowledge with the poor. Lastly, despite encouragement of international collaboration, fast-paced funding calls do not allocate sufficient time to build relationships with the poor primary stakeholders. We suggest the possibility that maintenance of this disconnect is intentional, reflecting a broader power dynamic in which the global and local elite dictate the lives of the poor based on geopolitical interests and national priorities.