The open vehicle routing problem (OVRP) is one of the most important versions of vehicle routing problem (VRP) in which the vehicles are not required to return to the depot after completing service. Because this problem belongs to NP-hard Problems, an efficient elite ant system called EEAS is proposed in this paper in which a new state transition rule, and a new pheromone updating rule are used for more improving solutions. These modifications avoid the premature convergence and makes better solutions. Computational results on several instances show that the proposed algorithm finds closely the best known solutions for most of the instances in which eight best known solutions are also found. In addition, the EEAS is comparable in terms of solution quality to the best performing published metaheuristics.
