From now until the end of the year, around 4.8 million people from the UK will have to pay £62 million to credit card companies in charges because they will use their plastic while abroad, according to the Post Office.
For the rest of 2010 an estimated £3 billion will be spent on credit cards in foreign countries.
A survey by the Post Office suggests that of those who plan to use plastic while abroad, 13% say they do not know if their lender will place charges on them for using their card; even more people say they know they will be charged for the privilege but they will carry on regardless.
Around a quarter of those polled who plan to use their credit card say they are aware of the extra charges and around three in 10 say they do not know what the charges amount to but are sure they will occur anyway.
The Post Office's Az Alibhai said: "This summer millions of travellers will waste money on unnecessary fees and, worryingly, many are not even aware of how much this will increase their holiday spending."
