This study investigates the effectiveness of an electromagnetic water treatment (EMWT) system in improving the physicochemical quality of tap water through a controlled laboratory-based experiment. The system applies pulsed electromagnetic fields to flowing water, eliminating the need for chemicals, membranes, or filtration media. Two tap water samples underwent identical EMWT exposure, and seven key quality indicators were analyzed before and after treatment: pH, electrical conductivity (EC), TDS, total hardness, salinity, calcium and magnesium ion concentrations, and dissolved oxygen (DO). The results revealed notable improvements: EC decreased by 28.0% and 29.2%, TDS dropped by 44.3% and 43.5%, total hardness declined by 8.0% and 8.5%, salinity was reduced by 24.2% and 21.4%, calcium and magnesium concentrations dropped by up to 14.3%, while DO increased by 21.4% and 22.6%. The pH values stabilized at a neutral level (7.4 ± 0.2). These findings suggest that EMWT may influence ionic mobility, microstructural arrangement of dissolved species, and gas solubility. Overall, the system demonstrates promising potential for enhancing water quality in applications requiring reduced salinity and hardness and improved oxygenation.