Currency conversion fees, also known as foreign transaction fees, were untouched by the CARD Act. In fact, most major card-issuing banks now charge a 3 percent fee for foreign currency transactions, and even if you're not a jet-setter, you could find yourself stung. Sherry says that banks apply this fee to any transaction that's conducted by a bank outside U.S. borders, even if you're paying in dollars. For instance, if you shop online, you could get hit with this fee if the seller is based overseas or if they route their transactions through a bank outside the country. Three percent might not sound like a lot, but if you're on a weeklong trip to another country, those small amounts can add up quickly.

To find out if a card charges this fee, consumers must look at the rate and fee disclosures from the card issuer or call customer service. Capital One is one major issuer that doesn't charge these fees. Other issuers have recently started waiving the fee on premium cards.