This document discusses minimizing harmonic distortion in a distribution system caused by electric vehicle charging stations (CS). It presents a model of a 10-bus radial distribution system with 6 CS installed to analyze harmonic distortion. A harmonic load flow analysis is performed to determine voltage and current harmonics. CS and battery models are developed considering harmonic distortion levels and state of charge. Single tuned passive filters are modeled as a method to mitigate harmonics. A metaheuristic technique called Modified Lightning Search Algorithm is used to find the optimal placement and sizing of passive filters to minimize harmonic distortion and losses in the system.