The ability of structural slabs to withstand contact blast is a critical determinant of building resilience in environments prone to explosive threats. While much of the existing research assumes idealized full support conditions, real-world scenarios often deviate due to aging, degradation, or construction limitations, leaving many structures partially supported. Despite the prevalence of such conditions, the influence of varying edge support on slab performance under blast loading remains poorly understood, creating a critical gap in literature. This study addresses this issue by investigating the behavior of a 75 mm-thick reinforced concrete slab with dimensions of 1000 mm × 1000 mm subjected to a contact blast equivalent to 0.28 kg of brick-shaped TNT. Using advanced numerical simulations combining the Eulerian and Lagrangian approaches within a Finite Element Analysis (FEA) framework in Abaqus software, the slab's response is evaluated for different edge support scenarios, ranging from full support (100%: validated) to progressively reduced support (90%, 80%, 70%, 60%, and 50%) along the slab's two opposite edges. Analysis results reveal that decreasing clamping levels from 100% to 50% significantly weakens the slab's structural integrity, leading to larger perforations, increased plastic damage energy, and a shift from shear-dominated to flexural and tensile failure modes. These findings emphasize the critical role of edge restraint in mitigating blast-induced damage and enhancing structural resilience under extreme loading conditions. This research fills the knowledge gap in blast-resistant design for partially supported structures and offers practical insights for enhancing infrastructure resilience in uncertain or deteriorating support conditions.