Resumen
In the last decades, tax fraud has grown, being catalogued as a serious impediment in the way of economic development. The paper aims to make contributions on two levels: a) Theoretical level - by synthesis methodologies for estimating tax fraud and b) Empirical level - by analyzing fraud mechanisms and dynamics of this phenomenon, properly established methodologies. To achieve the objective, we have appealed to the qualitative and quantitative analysis. Whatever the context that generates tax fraud mechanisms, the ultimate goal of fraudsters is the same: total or partial avoidance of taxation, respectively obtaining public funds unduly. The increasing complexity of business (regarded as a tax base) and failure to adapt prompt of legal regulations to new contexts have allowed diversification and ?improving? the mechanisms of fraud, creating additional risks for accuracy estimates of tax fraud.