Foreign transaction fee
A foreign transaction fee is a charge, often around 3% of the purchase, that some credit and debit cards add when you buy in another currency or from a merchant abroad.
Many travel cards charge none. Paying in the local currency is usually cheaper than letting the merchant convert to dollars (dynamic currency conversion), which adds its own markup.
Related terms
Sources: CFPB: Regulation Z, 12 CFR 1026.6