<p>The major problem with landfill sites is the production of leachates, complex dark liquids containing various pollutants. Due to the significant environmental risks posed by these leachates, developing and implementing effective treatment methods to degrade and remove the targeted pollutants is essential. The novelty of this work lies in the simple and effective combination of aeration and coagulation with ferric chloride to remove nitrogenous compounds and color, supported by statistical analysis and practical application at the Ouled Berjal landfill site (Kenitra, Morocco). The leachate was aerated for 2, 4, 8, and 24&#xa0;h, followed by the addition of varying coagulant doses to determine the optimum. The results showed that the combined aeration and coagulation treatment significantly reduced nitrogen pollution in landfill leachates, achieving removal efficiencies of 72% for NH₄⁺, 40% for NO₃⁻, 27% for NO₂⁻. Compared with ozone technology, our process achieved superior removal efficiencies, including 100% colour removal, whereas ozone technology achieved only 87.5%. This study stands out from previous work due to its simple yet effective approach using a low dose of ferric chloride, which lowers costs and makes the process economically viable at an operational scale, while applying extensive statistical analysis (ANOVA) to quantify the effects of aeration duration and coagulant dose. Moreover, it provides data directly relevant to the local context of the Ouled Berjal landfill. Overall, this combined treatment proves effective in reducing the pollution load and improving landfill leachate quality. In addition, the combined treatment generated a low quantity of sludge, which reinforces its economic and operational feasibility.</p>