In 1993 Ernst Homburg was senior research fellow at the Sidney M. Edelstein Center of the Hebrew University of Jerusalem.
In 1998/1999 he was a fellow at the Netherlands Institute of Advanced Study, Wassenaar.
In 2002 he was a fellow at the Max-Planck-Institut für Wissenschaftsgeschichte in Berlin.
In 2014 Homburg received the HIST Award for Outstanding Achievement in the History of Chemistry, from the Division History of Chemistry ("Hist") of the American Chemical Society (ACS).