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Chile, located along the Pacific Ring of Fire, exhibits one of the highest levels of seismic activity worldwide, with major earthquakes such as Valdivia (Mw 9.5, 1960), Valparaíso (Mw 8.0, 1985), and Maule (Mw 8.8, 2010), the latter of which revealed critical vulnerabilities in reinforced concrete wall buildings. Although the national seismic code has been strengthened following these events, its provisions remain largely qualitative regarding expected performance levels and lack quantitative criteria defining acceptable collapse risk thresholds. In this context, several studies have advanced the characterization of the seismic vulnerability of Chilean buildings; however, most have focused on specific case studies without systematically addressing the multiple design variables relevant to a comprehensive assessment of structural risk. This study evaluates the seismic vulnerability of medium- and high-rise residential buildings in Chile, characterized by reinforced concrete walls with Y-shaped sections. Seventeen archetypes were modeled in OpenSees, varying height, stiffness, site class, seismic zone, and design era (pre- and post-2010). The structural response was analyzed through nonlinear static and dynamic analyses, which formed the basis for a Multiple Stripe Analysis (MSA) using Chilean ground motion records. From this approach, collapse fragility curves were derived using maximum likelihood estimation, and seismic risk metrics such as the mean annual collapse rate (λc) and the 50-year collapse probability (Pc(50)) were computed. Results indicate that the 50-year collapse probability increases with building height, reaching critical levels for 25-story buildings, while 10- and 15-story archetypes exhibit the most favorable performance. Regarding site conditions, a reduction in vulnerability was observed from Site Class A and B to Site Class C. Additionally, buildings located in Seismic Zone III show higher collapse probabilities than those in Zone II. Finally, post-2010 designs present a lower probability of collapse compared to pre-2010 designs, although the differences remain modest.