Andrew Brown, of Post Office Travel Money, said: "With continuing uncertainty about sterling, it is more important than ever for people planning winter-sun holidays to do their homework and pick a destination at which prices for tourist staples are low.
"In a Twitter poll last week, over half of the 14,000 people who took part said hotel and flight costs are their major concern but the truth is that resort prices can make a big difference to the holiday budget.
"Japan looks very affordable these days, with low prices for meals and drinks in a wide range of centrally located restaurants and bars.
"It is also good news that prices have dipped in popular Caribbean islands."