Road freight transport has a major impact on society with external effects such as congestion, air pollution and carbon emissions. Therefore, the European Commission stimulates the more sustainable alternative Intermodal Freight Transportation (IFT). To increase the share of IFT, it is needed to know the performance of the current IFT-network. In this research, a methodology to assess performance of chains in IFT is developed. The developed Weighted Slacks-Based Data Envelopment Analysis model takes into account parallel and overlapping divisions and different structures of chains. The method is tested with a numerical example and a sample of real European IFT chains and solves issues of a compared Data Envelopment Analysis model. The methodology is then implemented to the rail and transshipment part of the North Sea – Mediterranean and Rhine – Alpine freight corridors.