This invention provides the ability to load balance calls in a communications network using a certain criterion, such as a user-specified call priority, or the call class of service. The method is applied when selecting a route for a new call or for re-balancing the calls across a network. When the user-specified call priority is used, the aggregated number of calls with the same priority or class of service is calculated for all possible routes the new call may use. The aggregated number of calls is then divided by the number of hops in the respective routes; the route with the smallest ratio is selected for the new call. Re-balancing is performed by re-routing the calls in such a way as to obtain a similar number of calls of the same priority, or class of service, along all possible routes.