The complexity of the Brazilian electrical system has a number of actors structured as a value chain, from the generation phase, followed by the transmission, marketing, distribution reaching the end user. The efficient and responsible performance of each partner results on the high quality service performed under the supervision of external agencies legislating all activities related to generation, commercialization and distribution of electricity. This study focuses the end players (distributor and consumer) where the critical point is the price that the consumer pays to the distributor utility. This payment ensures a fair economic return of investments made by the utility company while ensuring quality of services provided at reasonable prices. In this context, a computational tool was developed to estimate the monthly billing for different tariffs, guiding consumers to suit their needs. The tariff simulator developed is based on a mathematical model which allows three types of comparisons: inter dealer billings; billings inter tariff posts at a fixed time of year, and tariff comparisons based on monthly historical data for one-year period. Results of simulations performed produced relevant data helping consumers to decide whether or not they should maintain their energy contract with the utility or replace it to a more economic one.