Alkhudhairy FI – This research scrutinized the impact of curing intensity on mechanical properties of different bulk–fill resin–based composites (RBCs). The data presented in this work showed a higher curing light intensity (1200 mW/cm²) had a positive influence on the compressive and tensile strength of the four bulk–fill RBCs and microhardness of two materials tested compared with lower curing light intensity (650 mW/cm²). It was found that SonicFill demonstrated the greatest microhardness and compressive strength significantly for both curing light intensities and greater diametral tensile strength with high–intensity light, although not significant. On the other hand, Smart Dentin Replacement (SDR) cured with high–intensity light displayed the greatest diametral tensile strength among the four materials.