How to avoid unexpected roaming bills outside the EU this summer

These days, your photos are processed instantly and for free, but the cost of letting someone back home see them can add up to almost as much as your hotel room.

Mobile phones are the default devices now for taking and sharing pictures, but while you can snap to your heart’s content at home, without straying outside the limits of your tariff, you could be charged more than £50 for sharing a single photo from overseas.

The hidden cost is in the data roaming that allows phones to the access the internet from outside their usual network.

Within the EU this is not a problem – though it used to be and may be again after Brexit – because a “roam like home” policy means you can carry on as if you were in your back garden. But in other countries, the cost varies enormously.

The consumer group Which? discovered that in some parts of the world, taking a single picture could eat up your entire daily allowance if you forget to turn off the setting that automatically uploads it to a cloud service like Google Photos.

Even if your contract has a lower daily cap – £35 is typical – you might not get change out of £500 if you hit it every day for a fortnight.

It’s not only photos that can burst your budget. Streaming a single song could cost more than £30 on some contracts, which is more than the cost of three online albums back home. And glancing a few times at Google Maps to help find the nearest beach can cost around a fiver.

All of these services rely on mobile data. We take this for granted at home, but outside the regulated EU it’s a precious commodity. It does depend on your tariff, though. Which? found that downloading a PDF of a plane ticket in the Gulf could cost £31 on Virgin Mobile but only 50p on GiffGaff.

If your contract is outside its minimum term, shopping around for a new one should be as much a priority before you head off as buying sun cream. If not, there are a few settings to check on your phone before you get on the plane.

The catch-all is to put it into flight mode when you set off and leave it in that state until you’re back in the UK. However, this will prevent any phone calls or texts getting in, as well as data getting out. Be aware, too, that it might unset itself if you turn on wi-fi or Bluetooth.

Turning off data roaming is a more subtle adjustment. All Android and iPhones have this option, and it means that your handset can function abroad as a phone but nothing else – though you can still use it to view anything you downloaded before you set off. If you can’t find the setting, or you don’t want to take any chances, you can call your network and ask them to disable it for you.

You can also turn off the “auto sync” option on apps you use a lot – but it may not cover all the bases, because many are set by default to go online discretely, and it’s hard to keep track of all of them.

If you do want to use the internet outside the EU, ask your network to switch you to a penalty-free package designed specifically for the purpose. They should be able to do this even within your minimum term.