The effect of using quantitative palaeobathymetric input in 1D tectonic modelling, 2D forward siliciclastic depositional modelling and 3D hydrocarbon migration modelling has been tested and quantified for northern North Sea datasets. In order to perform the latter, a 3D method for restoring palaeobathymetry has been developed, based on a previously documented 2D geometrical approach. Quantitative palaeobathymetry constrains the basin shape through geological time. Bathy-metric input has been shown to be important in defining tectonic phases in the post-rift phase in the northern North Sea and to constrain the possibility for slope failure and mass flows. In hydrocarbon migration modelling, it has been shown that palaeobathymetric input may change the migration direction through time, compared to modelling runs performed with no palaeobathymetric input.