Climate change will have far-reaching consequence for the future of tourism. A Climate Change Vulnerability Index for Tourism (CVIT) comprised of 27 indicators provides a transparent and systematic first analysis of the differential vulnerability of the tourism sector in 181 countries. Countries with the lowest vulnerability are found in western and northern Europe, central Asia, Canada and New Zealand. High sector vulnerability is found in Africa, Middle East, South Asia and Small Island Developing States. Vulnerability is highest in many countries where tourism represents the largest proportion of GDP and regions where tourism growth is expected to be the strongest over the coming decades. Climate change will pose an increasing barrier to tourism contributions to the Sustainable Development Goals.