The purpose of this paper consists in assessing the extent of financial integration in European Union using the Feldstein-Horioka criterion. More precisely, we test the crosscorrelation of savings and investment rates across European Union regions, using regional data from Regio and national statistical oces, over the period 1995-2000. Several important outcomes are reported by our article. First, we find that the financial integration seems to be realized inside each country, and we are able to rationalize the few puzzles we face. Second, we find that overall financial integration between EU regions is almost complete. After performing additional investigations on consistent sub-groups of regions, however, our analysis discards the illusion that the sole suppression of institutional barriers to capital mobility would be sucient