Christian Achilles completed an apprenticeship as a savings bank clerk at Kreissparkasse Göttingen after graduating from high school and completing his basic military service. He then studied law at the Georg-August University of Göttingen, graduating with the 1st State Examination in Law and the subsequent legal clerkship with the 2nd State Examination in Law.
From 1989 to 1995 Achilles was personal advisor to the President of the Bundestag, Prof. Dr. Rita Süssmuth, and from 1995 to 1998 personal advisor to President Dr. Dietrich H. Hoppenstedt and deputy head of department for fundamental issues at the Savings Banks and Giro Association of Lower Saxony in Hanover.
Since November 1998, he has been Head of the Press and Policy Department at the German Savings Banks and Giro Association in Bonn, and since July 1999 in Berlin. In April 2000 Achilles took over the management of the newly established Communications and Media Department of the German Savings Banks and Giro Association in Berlin, where all communication tasks for the DSGV and the Savings Banks Association are bundled.