Water is covered as a single issue in Sustainable Development Goal 6, as well as other SDGs such as disaster risk reduction, education, health, nutrition and gender. (UN-Water 2016a). Six targets are included in the water goal. Although global costing and cost-benefit studies have been previously conducted (Hutton and Varughese 2016, Hutton 2012), and a more recent study examined the approximate costs of an overall water goal (UNU and UNOSD 2013, UN-Water 2016b), a new study is required to understand the overall economic returns on expanding and sustainably operating WASH services according to the new service definitions and target dates, as well as the extent to which additional financing can be sourced. This study confirmed that drinking water supply and sanitation both generate high economic returns to society, with returns exceeding costs for all interventions at both 3% and 5% discount rates. The study showed that economic returns varied between different regions of the world. This variation is partly expected due to different relative price levels of water and sanitation services, and different capacity to benefit (such as existing disease rates). The variation is also likely to be due to weak data for some regions and countries (e.g. unit costs of services for Central Asia, Oceania, North Africa, Western Asia and developed countries).