Brits jetting off need to be savvy about a crucial mobile phone rule at airports, or the Foreign Office warns you'll be left without your expensive tech items.

If you're planning to fly out of the UK this year on holiday, you must make sure your gadgets are charged up and ready to go – phones, tablets, and laptops included – or you might just have to wave them goodbye, reports Birmingham Live.

When it comes to what you can put in your hand luggage, the rules can be a bit of a head-scratcher and they're not the same for every airline.. However, one rule about electronic devices could catch you off guard – and you may be made to leave your phone at the airport.

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The rule states that if you can't show your tech item works by turning it on, you might as well kiss it goodbye at the gate. A similar rule applies if your phone is damaged so it's best to try and keep your items safe while on holiday.

The British Foreign Office has put it plain and simple, and states: "Make sure your electronic devices are charged before you travel. If your device does not switch on when requested, you will not be allowed to take it onto the aircraft.".

A laptop computer awaits inspection by airport security
A laptop computer awaits inspection by airport security

Most flyers won't get the third degree over their tech being up and running, but don't bet on slipping through as random checks are fair game at security. Even though the rule has been around for many years it seems a lot of holidaymakers are still in the dark and don't realise they risk having their phone or laptop removed from their possession.

Travel gurus at International Citizens Insurance have dropped a bombshell for those not clued up on airline dos and don'ts, warning: "If you cannot turn on your devices when requested by security personnel, they can take it from you, placing your holiday snaps in jeopardy."

British Airways is on the ball with stringent safety guidelines for flyers toting tech, insisting: "You can generally take electric and electronic items in your hand or checked baggage, but you need to follow specific safety instructions. Airport security staff may ask you to turn on electronic or battery-powered devices, such as phones, tablets, e-books and laptops, to demonstrate they function. If you're not able to do this, you will not be able to take your device with you."

Airport security check before flight. Passenger holding plastic bag with liquids above container with laptop and personal items.
Airport security has the right to remove things from your posession

BA added a crucial tip for travellers, and noted: "Please ensure that any items in your hand baggage are fully charged and switched on before you arrive at the airport. If your device is not charged, please place it in your checked baggage. If you are connecting, make sure that you do not deplete power in your devices during the first part of your journey as charging points at airports might be very limited and you may need an adapter."

Meanwhile, EasyJet's policy is crystal clear. It states: "You also need to make sure that your device stays charged if it runs out of battery and you can't turn it on to scan your boarding pass as required, easyJet cannot accept responsibility if you are as a result not able to fly."

Airlines like Ryanair, Jet2, TUI, and easyJet have their own list of items you're not allowed to bring on board. Obvious no-nos include anything dangerous like weapons and flammable liquids, but there's also a ban on e-cigs and some types of batteries in your checked bags. You can check the luggage rules on your airline's website – and you should check your airport's security rules too. You con't want to be caught out by packing hummus or jam in your lunch as they surprisingly count as liquids!

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