Make sure your credit card will work in the country you’re visiting. European banks have switched almost completely to the more secure chip-and-PIN technology, and fewer businesses abroad are accepting the outdated magnetic-strip cards.

Go to a bank or ATM in the country you’re visiting. The conversion centers in the airport or around the city tend to be huge rip-offs. You won’t get charged as many fees at the ATM or the bank, and the conversion will be exact.
Always have local cash. Not every place takes credit cards. Especially important places like trains or buses.

Call your bank or credit card provider. Sometimes banks think that fraud maybe occurring if transactions are suddenly happening in Bali when you’re from Jersey, and they will turn off your card as a security measure.

Check the country’s entrance/exit fees. Some countries require travelers to pay in order to enter or leave the country. These fees are not included in the price of your airline ticket, and can range from $25 to $200.