Britons claimed more than £1,300 on their medical bills for hospital treatments while abroad last year, average figures show.
The average treatment cost for illnesses and injuries suffered by British holidaymakers overseas rose to £1,333 in 2010, Sainsbury's Travel Insurance said.
Heart ailments were the costliest to treat for people overseas, with the bill averaging £8,148, while ear infections were the most common complaint cited on claims, with an average treatment cost of £320.
The study assessed the costs of medical treatment in 10 different countries based on claims filed last year.
Travellers who fell ill while in the US forked out the most for hospital care, at an average of £4,726. In contrast, the average treatment cost in Greece was 10 times lower at just £422.
Spain, Turkey and Greece were the three top destinations where holidaymakers were most likely to require medical care, the study found.
Scott Gorman, of Sainsbury's Travel Insurance, said: "It has been widely reported that healthcare costs are rising far faster than the rate of inflation, not just in the UK but in other countries as well, so ensuring you have adequate cover and peace of mind while you travel abroad is more important than ever."