Over the past decade, the complexity of operations in the port area has increased significantly. As global trade increased significantly, vessel sizes and cargo volumes surged, which places additional pressure on the ports' (physical) assets. Both the challenges the ports are facing and the willingness to ensure continuous improvement have contributed to a growing interest in benchmarking. Four European ports - Port of Rotterdam, North Sea Port, Port of Hamburg, and Port of Gothenburg - entered into a cooperation to realise a platform for benchmarking. Currently, limited research is available on methods for assessing and comparing asset management performance. This research aims at filling the gaps in literature by developing an international benchmarking model for ports. In doing so, it provides asset managers a structured approach to develop benchmarks in order to measure and compare performance. By combining existing frameworks and the consultation of experts in the research field, a model design is obtained in a collaborative way. The model is demonstrated by means of a case study. Following this demonstration it can be stated that the benchmarking model provides asset managers a clear working method and supporting tools. The presented benchmark results, and the process itself, provides asset managers valuable insights into performance. Consequently, it provides support in the development of future benchmarks.