The objective of this paper is to present a computer program developed for Windows to compute reliability indices for different customers and sets of customers supplied by the same distribution feeder. This program deals with information obtained directly from utility databases to create equivalent network modeling and carry out contingency analytical simulations. The system's average failure rates must be informed by the user, based on historical utility data, manufacturer test data or typical values. The program enables one to compute penalties and annual costs of energy interruptions and compare the obtained indices with the reliability index targets set by the national regulatory agency (ANEEL) for the different sets of customers and distribution feeders under analysis. The program allows to analyze the influence the variation of the system rates and also modifications of the topology of the network and, thus, to carry out a sensitive study to verify the effect of some different protection equipment and modifications in the topology of the systems, justifying investments that can improve the reliability, the power quality, and reduce costs of energy interruption and other related costs.