X0101 EFFECT 33 LIVE 2011-05-02 0001193125-11-073853 485APOS 0000770540 Natixis Funds Trust I 002-98326 S000006658 Natixis U.S. Diversified Portfolio C000018161 Class A S000006658 Natixis U.S. Diversified Portfolio C000018162 Class B S000006658 Natixis U.S. Diversified Portfolio C000018163 Class C S000006658 Natixis U.S. Diversified Portfolio C000018164 Class Y