Although electrochemical methods are one of the most efficient approaches for treating wastewater, the type of wastewater to be treated, the type of electrode material employed, and the polarity direction all significantly affect how well these systems work. The prospective application of the proposed materials for the purification of slaughterhouse effluent has not been sufficiently explored in earlier studies, despite the fact that the materials (copper and stainless-steel) are reasonably inexpensive and easily accessible, especially in low-income countries. It is also unfortunate that previous research has not taken into account the potential effect of polarity direction in stainless-steel and copper electrode materials used for the purification of slaughterhouse effluent. This study investigated the potential effect of polarity direction for the purification of slaughterhouse wastewater using stainless-steel and copper electrode materials. Two electrode polarities were used in the study; stainless-steel (anode) to copper (cathode) and copper (anode) to stainless-steel (cathode). The potential effect of the contact time on the pollutants’ removal was also taken into account. Generally, the copper-to-stainless-steel polarity showed a relatively high removal efficiency compared to the stainless-steel-to-copper electrode polarity. For instance, under 20 min of contact time, the removal efficiencies of copper (anode) to stainless-steel (cathode) were higher than that of stainless-steel (anode) to copper (cathode) in 11 out of 14 investigated water quality parameters. From 40 min contact time, the copper (anode) to stainless-steel (cathode) performed higher than that of stainless-steel (anode) to copper (cathode) in 8 out of 14 investigated water quality parameters. Moreover, from 60 min contact time, the copper (anode) to stainless-steel (cathode) performed higher than that of stainless-steel (anode) to copper (cathode) in 11 out of 14 investigated water quality parameters. Based on the findings, it is clear that, in order to obtain desired performance, contact time and polarity direction should be carefully considered when developing electrochemical wastewater treatment systems.