Check the day's rates at Web sites like Bankrate, XE.com or Yahoo's Currency Converter. If you have an iPhone or iPod Touch, Banas suggests the free Currency app, which provides real-time information for more than 50 currencies in 70 countries.
5. Buy traveler's checks in local currency. While ATMs and credit cards often offer the best rates, traveler's checks are a solid backup option if your card doesn't work or gets stolen. U.S. dollars aren't a good idea -- they're easily stolen and expensive to exchange.
However, it may be wise to purchase checks in a local currency, says Joseph Sobin, the owner and travel executive of Denver-based Colorado Concierge Services.
Sobin suggests Sterling- or euro-denominated traveler checks, which hold value in a swinging currency exchange market.
"I may have clients buy traveler checks in the local currency before they leave the U.S.," Sobin says. "It keeps them on a budget and they don't have to worry about exchange rates and fees once at their destination."
Shop around for checks; ask banks about exchange rates, commissions and fees charged.
6. Prepay your way. Best Western hotels -- a quality option in Europe, according to Sobin -- offer a prepaid hotel card for jet-setters.
Pay in your home currency, and the currency is converted to units that can be spent in U.S. dollars, euros or Canadian dollars. When it's time to pay for your night's stay, the card's amount is converted to local currency at a rate closely matching the actual exchange rate -- and you won't pay currency conversion fees.
Likewise, you may be able to use your frequent-flier miles or hotel rewards cards to score free overseas nights.
7. Ready your rapid-math skills. Get quick at converting the foreign currency into dollars -- whether via calculator, handmade chart or mental-math acuity.
"It's easy to waste money when you forget that a one euro coffee is not actually a cheap $1 cup of java," Zaraysky says.
"Remember the dollar equivalents of typical prices -- 1 euro, 5 euros, 10 euros -- to keep yourself from buying little trinkets or snacks that you most likely don't need and will cost you more than you think," she says.
8. Beware buck changers. Hotels, stores and other establishments may offer to exchange cash or travelers checks, or allow you to pay for your credit-card purchases in dollars. But watch out for hidden fees or poor exchange rates.
But because you know the current rate -- tip No. 4 -- you'll spot whether the hotel's exchange rate is fair. Ask if there's an extra fee for transactions or whether you'll find any surprises on your card bill.
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