It's time for your first trip abroad in years. You've got everything ready to go. Clothes? Check. Toothbrush? Check. Passport? Check. Looked up the fees that my credit and debit cards charge for foreign-currency transactions? Ch ... huh?

Financial institutions are increasingly using foreign-currency transactions as a way to add to their fee income. For instance, say you use a credit card for a purchase. Card networks such as Visa and MasterCard (NYSE:MA) charge a 1% fee. American Express (NYSE:AXP) charges a 2% fee. In addition to the card network, many card-issuer banks, including Wells Fargo (NYSE:WFC), Bank of America (NYSE:BAC), and the Citibank division of Citigroup (NYSE:C), tack on an additional fee of up to 2%.

What about debit cards? Same problem -- Visa or MasterCard will take their 1%, and depending on what bank you use, you might face exactly the same additional 2% fee.

How about going to an ATM? There, you might face even more trouble: In addition to the network and bank foreign-exchange fees, the foreign ATM will often charge you a transaction fee, and your bank will charge you an additional fee for using a non-network ATM. This can easily bring the total charge for a small ATM withdrawal to 3%-5% or more.

However, not all card issuers charge these fees. The easiest way to find out whether your bank charges is to call the customer service number on your credit or debit card. If you have more than one credit or debit card, the answer will tell you which card is better to use while traveling.

Even with these fees, most alternatives to credit and debit cards are still worse. Foreign-currency booths, such as those seen at airports, often give extremely unfavorable rates. You can generally see just how bad the rates are by comparing the rate at which they buy back a foreign currency with the rate at which they sell the foreign currency to you. Because your foreign credit card transaction is just one of millions processed every day, your card network and issuing bank get favorable exchange rates. Similarly, some foreign merchants may offer to accept payment in U.S. dollars, but the exchange rate they offer is usually much less than the bank rate.

You shouldn't let these fees keep you from having fun on your vacation. With a little research, however, you might come home to a little less pain when the bill arrives.

For related Foolishness:

Bank of America is just one of the recommendations of our Motley Fool Income Investor newsletter service, which finds the market's best dividend-paying stocks. Sign up today -- it's free for the first month.

Fool contributor Dan Caplinger travels with rolled-up $100 bills in his socks. He doesn't own shares of any of the companies mentioned in this article.