I'm purchasing tickets from Europe to the US on delta.com, and the prices are coming up in Euros. We're trying to decide which credit card to use to purchase them--the German card or the US. Does anyone know where the transaction comes from? In other words, does Delta in the US convert the Euro charges to dollars and then charge your card via Delta in the US (so no foreign transaction fee on a US card) or does the charge originate in Europe (meaning that if one's US card has a foreign transaction fee, one gets hammered with it)? We're purchasing multiple tickets for family to visit us in the US over the holidays, and Delta customer service can't answer the question.