Call your credit card company before you go and tell them you will be traveling overseas for an extended period of time, especially if you’re taking cards you rarely use. Credit card companies have elaborate fraud-protection systems in place and they utilize your credit history. If you never use your card and you’re suddenly making $500 purchases, while overseas at that, there is high probability that your card will be denied until they can ascertain that it hasn’t been stolen. Save the company – and more importantly, yourself – the trouble and let them know in advance.