We also have an American Express but it is a Costco TrueEarnings card. They charge 2.7% fee. Our credit union debit card charges 2%. And... I double-checked the Visa (Chase/Amazon) again and what do you know? They are now charging 3%. One more card to check, hubby's company Citibank card. Really don't like to carry a lot of cash so we may be using the debit card.