Reverse osmosis (RO) is becoming one of the most promising technologies used in wastewater treatment because it offers high rate of contaminant rejection and lower energy consumption in comparison with other thermal treatment processes. Earlier research by the same authors in respect of a distributed 1‐dimensional mathematical model for a single spiral‐wound RO membrane module based on the solution–diffusion model has been used in this paper to simulate the rejection of N‐nitrosodimethylamine (NDMA) from wastewater in a series of 7 RO elements full‐scale treatment plant. First, the applicability of this model has been evaluated using a simulation study, and the results have been compared against experimental data gathered from the literature for a given plant. Second, further simulation and analysis studies are carried out to assess the performance of the plant for NDMA rejection and recovery rate under different operating conditions of feed pressure, flow rate, and concentration. For the studied RO configuration, it is concluded that a maximum of 55.1% NDMA rejection can be achieved, which confirms the remaining issue of lower NDMA rejection.