After eight years as solo clarinettist with the Berliner Symphoniker, he moved in 2004 in the same position to the Staatsphilharmonie Nürnberg.
From 2006 to 2007 he was solo clarinettist with the SWR Symphony Orchestra Baden-Baden and Freiburg.
As a guest he played in a variety of renowned orchestras and others such as Bavarian State Orchestra, Berliner Philharmoniker, Radio Philharmonic Orchestra of the NDR Hannover, Württemberg State Orchestra Stuttgart, Dresden Philharmonic, Staatskapelle Dresden, Orchestra of the Deutsche Oper Berlin, Kammerphilharmonie Bremen, Essen Philharmonic, Museum Orchestra Frankfurt, Münchner Rundfunkorchester, Komische Oper Berlin, Dortmunder Philharmoniker. In November 2018 he appeared as a soloist at the Mozart Festival Eifel with Mozart’s Clarinet Concerto.
Since the winter semester 2013, Felix Löffler has been Professor of Clarinet and, since 2017, Vice Rector at the Hochschule für Musik in Mainz – Allemagne.