In the Netherlands the groundwater-surface water interaction processes vary spatially and temporarily. In this article we present maps of the spatial distribution of monthly water exchange modelled with the National Hydrological Instrument of the Netherlands (NHI) for three years that represent a dry, an average and a wet year. Additionally, for five characteristic regions we present the exchange in more detail, both the temporal variability and the origin of water fluxes. The simulation results provide a better understanding of the hydrogeological system. The Dutch water authorities use the maps in the planning process of measures to fulfil the framework directive of the European Union.