In this work a mixed agent-based and discrete event simulation model is developed for a high frequency bus route in the Netherlands. With this model, different passenger growth scenarios can be easily evaluated. This simulation model helps policy makers to predict changes that have to be made to bus routes and planned travel times before problems occur. The model is validated using several performance indicators, showing that under some model assumptions, it can realistically simulate real-life situations. The simulation’s workings are illustrated by two use cases.