Nature-based solutions (NBSs) can help adapt to climate change, particularly regarding sea level rise, storm surges, and extreme rainfall. To better assess their impact, positive externalities like public health, biodiversity, and eco system services such as water purification and carbon sequestration, should be included in cost-benefit analyses (CBAs) for climate adaptation decisions. This report presents six NBS case studies from Nordic countries, where positive externalities are monetized by using benefit transfer techniques, and discusses how this affects CBA outcomes. Our results show that including these externalities significantly increases social benefits, potentially shifting CBAs from net costs to net benefits.