The electrification of the transport sector will have a substantial impact on the Swiss electricity system. Vehicle-to-Grid (V2G) – the bidirectional interaction between electric vehicles and the grid – is one way of leveraging the battery capacity to provide flexibility for the electricity system. In this study, we make a first estimate of the potential impact of V2G on the Swiss electricity system. We hereby assume that V2G is used for balancing supply and demand on a system level.