The purpose of this study was to examine two biomass district heating plants operating in Tuscany, with a specific focus on the ex-post evaluation of their economic and financial feasibility and of their environmental benefits. The former biomass district heating plant supplies only public users (Comunità Montana della Lunigiana
, CML: administrative body that coordinates the municipalities located in mountain areas), the latter supplies both public and private users (Municipality of San Romano in Garfagnana
). Ex-post investment analysis was performed to check both the consistency of results with the forecasts made in the stage of the project design and on the factors, which may have reduced or jeopardized the estimated economic performance of the investment (ex-ante assessment). The results of the study point out appreciable results only in the case of biomass district heating plants involving private users and fuelled by biomasses sourced from third parties. In this case, the factors that most influence ex-post results include the conditions of the woody biomass local market (market prices), the policies of energy selling prices to private users and the temporal dynamics of private users’ connection. To ensure the consistency of ex-post economic outcome with the expected results it is thus important to: (i) have good knowledge of the woody local market; (ii) define energy selling prices that should be cheap for private users but consistent with energy production costs and (iii) constrain private users beforehand to prevent errors in the plant design and in the preliminary estimate of return on investment. Moreover, the results obtained during the monitoring activities could help in providing information on the effectiveness of the supporting measures adopted and also to orient future choices of policy makers and particularly designers, to identify the most efficient configuration of district heating organization for improving energy and environmental performances of communities, and to develop a chain model for the optimization of energy use in the municipality.