This research article aims to assess the impact of substituting fine aggregates in concrete with Ceramic Waste Powder at different proportions (conventional, 5%, 10%, 15%, and 20%) on the deflection behaviour of reinforced concrete beams. This study aims to identify the optimal replacement percentage that minimizes deflection compared to conventional concrete, consequently enhancing structural performance. This article presents the results of an experimental investigation into the impact of Ceramic Waste Powder (CWP) on concrete’s mechanical properties and performance. The study assessed concrete specimens’ compressive strength, split tensile strength, and deflection behaviour with varying CWP replacement percentages. The results demonstrated that adding CWP had a negligible impact on concrete’s compressive and split tensile strength. However, the deflection behaviour of the concrete beams with 10% CWP replacement was superior to that of conventional beams. This indicates that incorporating CWP into concrete can enhance structural performance. Ultrasonic Pulse Velocity (UPV) tests demonstrate that incorporating 10% CWP into concrete preserves the structure’s integrity, presenting CWP as an environmentally friendly production alternative. The findings show the viability of CWP as an option for sustainable waste management in the construction industry. To achieve a balance between improved deflection behaviour and acceptable strength characteristics in concrete structures, a 10% CWP replacement level is recommended. © 2023 Elsevier B.V., All rights reserved.