The purpose of this paper is to evaluate a particular competitive interaction among Brazilian states, the Fiscal War of Ports (FWP) and to verify if Resolution 13/2012, which reduced the tax rate on imported goods in interstate sales, had the desired impact. Using monthly data on state importing levels during the period January 2010- April 2015 we find evidence that Brazilian states do engage in spatial interaction, and that R13 has changed the spatial interaction among states since 2013 and more deeply in the beginning of 2014.