Customers without comprehsive travel insurance could pay as much as £12 per minute for hospital treatment abroad, says American Express.
The travel insurance provider found that American hospitals are so expensive treatment could cost thousands of pounds while a night in a Caribbean hospital could set travellers back over £1,700.
American Express says almost three million Britons risked their health - and their wallet - last year by not taking out travel insurance.
Brits travelling outside the EU should be particularly careful, says American Express, since bills can be much higher.
Joanne Field, American Express marketing manager, said: "Apart from skiing in Europe, Britons tend to travel further afield at this time of year to find the sun. Without good travel insurance literally millions are at risk from expensive medical bills.
"A broken leg in the US can cost £25,000, while an average claim for a hospital stay in the Caribbean was £1,703.
"Travel insurance is an essential part of holiday pricing and not a luxury extra to be ignored - we would encourage everyone to travel with comprehensive emergency medical cover which a good travel insurance policy provides."To read more about Travel Insurance, click here.
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