Evaluating social welfare and redistributive effects of Spanish personal income tax reform

Spain has recently concluded a process of wide-ranging reform of its personal income tax (IRPF), in force since 1992. The new IRPF is applicable from 1999 onward. The aim of this article is to analyse the implications of this tax reform for the distribution of personal income, and additionally to provide a comparative evaluation in terms of social welfare of both taxes. Empirical analysis is performed by a simulation exercise, employing the microdata contained in the Institute of Fiscal Studies’?IRPF Panel of Taxpayers. The analysis shows that the new IRPF induces a redistributive effect slightly lower than the old IRPF. The greater redistributive potential of the progressive structure of the new tax proves to be insufficient to compensate for the contrary effect caused by reduction in the level of tax liability. However, this new tax unambigously permits, in an inequality-adverse society, a higher level of social welfare than that attained by the old tax.