A simplification of the German tax law is the major intend when proposing a graduated tax rate to replace the current German formula based tax scale. A plain tax rate structure requires catchy tax brackets (e.g. in 5.000 € or 10.000 € steps) and tax rates (e.g. tax rate differences of 5% or 10%). Our empirical analysis shows that such a graduated tax rate causes significant distributional effects and, depending on the particular form, affects different groups of tax payers in different ways. This holds in particular for the two graduated tax rate proposals from the German Liberal Party which additionally provoke substantial revenue losses. A graduated tax rate with little revenue and distributional effects compared to the current formula based tax scale lacks a plain structure and hence conflicts with the objective of tax simplification. © 2011 Verein für Socialpolitik.