A foreign transaction is any card payment made in a currency that isn’t euros. When this happens, the amount is converted using the Mastercard exchange rate.
Mastercard sets their own, daily exchange rate, which may differ from the European Central Bank’s.
You can use Mastercard’s Currency Conversion Calculator to work out the daily rate for a transaction. This rate is applied at the moment the payment clears, so it may differ from what you see before you authorise the transaction.
