The 15-minute city model has recently emerged as a dominant human-centric urban planning paradigm, advocating for the fulfillment of all daily necessities—living, working, commerce, healthcare, education, and leisure—within a 15-minute walk from residence. While this model has gained traction in European and North American cities, its applicability to the urban contexts of developing nations, particularly Iran, remains largely unexplored. Approximately 27% of the total urban area and over 20% of the urban population in Iran reside in deteriorated and inefficient urban fabrics. These areas suffer from a confluence of physical decay, spatial inequality, deficient infrastructure, and deep-rooted socioeconomic fragility. Traditional urban regeneration interventions have predominantly focused on physical retrofitting (renewal and structural reinforcement), often neglecting functional daily needs, spatial justice, and social empowerment. This study aims to bridge this gap by evaluating the feasibility of implementing the 15-minute city model within the deteriorated northeast district of Tehran (District 4, Zone 8), a representative case marked by high population density, an inefficient street network, a severe shortage of neighborhood services, and vulnerable socio-economic demographics.