Also, your bank may truthfully tell you that they do not charge foreign transaction fees, though both Visa and MasterCard themselves charge 1%. So your bank may or may not add anything on to that, but they might still pass along that 1% Visa and MC charge.
Here's one thing banks sometimes do where restaurants are concerned: When a merchant swipes your card, your bank puts a "hold" on those funds (by means of reducing your available balance). Some banks anticipate a tip of 20%, and add that to the amount they block. Then, when they receive the voucher, they adjust the amount charged to you.
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