The definition and measurement of citizens’ well-being is developing a wide scientific debate at international level both from theoretical and methodological point of view since they are considered in a multidimensional approach, abandoning the assumption that only the economic component is relevant. On this issue, economists, sociologists and statisticians are working together to define conceptual models and mathematical-statistical techniques that can measure it. Recently, the policy has shown great interest in linking the well-being indicators to the economic policy of national and local areas. In this regard, it seems important to calculate indicators up to a very small territorial level. The paper aims to present an experiment conducted on the municipalities of Basilicata where well-being indicators are calculated starting from administrative sources and big data; and then, composite indicators are computed in order to have a unidimensional measure that can help the policy makers to understand the complex reality.