Urbanisation exerts significant pressure on the integrity of riverine ecosystems, disrupting their structural complexity, function, and the supply of ecosystem services by aquatic biota. The Buffalo River, a critical freshwater system in South Africa, is subjected to various anthropogenic stressors, including industrial and domestic effluents and agricultural runoff. While considerable attention has been given to the diversity and composition of macroinvertebrate families, there remains a notable gap in understanding how urban pollution influences chironomid trait assemblages in South African rivers. This study seeks to address this gap by investigating the distribution of chironomid traits in the Buffalo River. Sampling sites were selected based on the predominant land-use in the catchment of the site. Chironomids and environmental variables were sampled seasonally from the selected sites between November 2021 and June 2022. The results show that traits and ecological preferences such as predatory lifestyle, shredding, crawling, swimming, medium body size (>10–20 mm) and preference for macrophytes, macroinvertebrates and wood were positively associated with the least impacted sites. Traits such as possession of large body size (>20-40mm), ventral gills, rigid tubes, laying of >1000 eggs per egg mass and preference for detritus were positively associated with highly impacted sites. These findings suggest chironomid traits and ecological preferences can be used to develop trait-based tools for urban river monitoring in South Africa.