<p>Recently, the world has been facing a crisis in water demand. Therefore, countries started to focus on wastewater treatment to address the shortage of freshwater. Since the concrete industry consumes vast amounts of water, researchers started investigating the incorporation of treated wastewater (TWW) in concrete instead of potable water. However, the impact of variations in the properties of TWW on the durability of concrete is still underexplored. This study investigates the influence of TWW on the mechanical properties and durability of concrete. Two secondary treated TWW samples were collected from different sources. The effect of using TWW for mixing and curing of concrete was evaluated through slump, compressive strength, modulus of elasticity, split tensile strength, water absorption, water penetration resistance, rapid chloride penetration, sorptivity, accelerated corrosion, and SEM analysis. Results showed that using TWW caused a reduction in compressive strength at early ages, while the reduction became negligible at later ages. Moreover, the impact of TWW on the durability was not significant, except for accelerated corrosion results as the mass loss was significantly higher compared to OPC. Moreover, variations in TWW properties affected its performance, as TWW with higher TDS showed better performance, due to the pore filling effect.</p>