Difficulty: 

Currency exchange rates are almost always better at your destination than at home. That said, it is often beneficial to have at least some local currency available when you arrive, for such things as porters, tips, and taxi fare. Although most airports and train stations have currency exchange offices, their hours are sometimes erratic and overseas flights often arrive during non-banking hours.
To avoid worrying your entire flight about whether the currency exchange office will be open, it makes sense to exchange a limited amount of money in advance of your trip. Once only possible at downtown banks in major cities and the American Express office, you can now purchase foreign currency online. To do so, follow these steps:
- Determine your currency needs. Before you visit the currency exchange site, determine your needs. Do you even need to exchange money into the local currency? Some countries, such as the Bahamas, accept US dollars as readily as their local Bahamian dollars.
If you do need to exchange your dollars into a foreign currency, estimate how much money you will need when you first arrive in the country. In most cases $100 worth of local currency will be plenty for a taxi ride and tips. However, in some cities where the airport is away from town and the cost of living is high, such as Tokyo, you will need to exchange more than $100. To get an idea of transportation costs, ask your travel agent or consult a current guidebook, such as a Frommer's or Fodor's guide. - Check the current exchange rates. Before visiting the exchange sites, check the current exchange rate to make sure you are getting a reasonable rate. The exchange rate is the cost of the foreign currency you are buying, in US dollars. American Express and other financial institutions have this information available on their Web sites. Some financial software programs, such as Microsoft Money, also offer this information. Keep in mind that exchange rates are only valid for the day they are quoted. The quoted rate will be the lowest bank rate. The currency exchange broker, in most cases, will add a service charge to cover their risk of handling the currency.
- Visit one of several Currency Exchange Web Sites. Once you know how much money you would like to exchange and what the best exchange rate is, go to one of several online currency brokers, such as ordercurrency.com and ezforex.com. These sites take a variety of forms of payment, including credit cards, wire transfer, and electronic bank drafts. Once paid, the currency is delivered to you via next-day delivery.
Caution:
Make sure to check the exchange rate before starting the transaction.
Quick Tips:
Exchange most of your currency overseas; you'll get a better rate.
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