Using your mobile in the US could cost €2,400

An analysis of roaming charges has found that consumers can be hit with charges of up to €2,400 for moderate use of a phone over a two-week trip to the US.

However, the research carried out by mobile phone tariff comparison app Killbiller.com found that if you are on a different network the costs can be much lower.

The analysis looked at the cost for typical usage of a smart phone over a two-week trip in Britain, in Spain and the US.

It was assumed the user would send five texts a day, make 10 minutes of phone calls each day and use social media for just 20 minutes.

In Europe, where there is a cap on roaming charges, the cost varies from €141 to just €2.99 over two weeks.

The survey looked at Vodafone, Three and Meteor, which between them have 90pc of the market here.

The results showed large differences in price across the different networks.

"Three is excellent value if travelling to the UK, but was the most expensive in Spain, and was extremely expensive if travelling to the USA, mostly due to prohibitive data rates," said Dr Bart Lehane of Killbiller.com.

"Vodafone was the cheapest for Spain and significantly cheaper than the competition for the USA. Meteor was most expensive to the UK, and was second in price for both Spain and the USA," he added.

But it was in the US that massive cost variations emerged, said Dr Lehane, whose doctorate is in computing.

Irish startup Killbiller.com allows people to download a cost comparison app on their phone for free showing how much their network charges for their usage and what other networks would charge. Killbiller.com found that the typical user over a two-week period will end up with a "bill shock" if they are with Three, as the bill could hit €2,407.

Data accounts for more than €2,000 of this total cost.