The amount you’d spent appeared on your bill. Maybe you paid a small conversion fee, but you also got a competitive exchange rate.

The dangers of dynamic currency conversion

Processing a credit card charge for overseas purchases used to be pretty simple. You swiped your card while on vacation, your bank changed the money from pesos or euros into greenbacks, and the amount you’d spent appeared on your bill. Maybe you paid a small conversion fee, but you also got a competitive exchange rate.