Cities are experiencing the impacts of climate change through water-related disasters, while the sustainable management of water resources remains crucial for urban climate resilience. Accordingly, frameworks that integrate urban water management with climate change adaptation become increasingly relevant. The Water Sensitive Cities (WSC) framework is built on three pillars that address cities’ role as communities and networks, water catchments, and providers of ecosystem services. A major element of the framework is the WSC index, which can be applied to assess cities by using multiple indicators under each pillar. With the objectives of adjusting and testing the WSC index in the context of the North Sea Region through a transdisciplinary knowledge co-production process, this paper presents the results from a self-assessment conducted by seven midsize cities. Insights gained from the comparison of self-assessment results are twofold. Firstly, the cities need to value the benefits of ecosystem services for climate change adaptation, and integrate climate change into other sectors. Secondly, the cities differ regarding the priority of climate change, and even the cities that aspire to be frontrunners have weaknesses. The application of the self-assessment process also creates an exchange and mutual learning platform for cities, and increases their awareness on climate resilience.