Martin Lewis warns millions of simple passport mistake that risks being turned away at the airport

The mistake that all Brits should know

Before you jet off abroad, you should carry out two essential passport checks, Martin Lewis has urged.

Prior to flying abroad there are two checks that every traveller needs to make, according to the MoneySavingExpert founder.

Miss either one and you could find out you are going nowhere, even if you thought you were all set and ready to go.

Here’s what you should do before you fly

First and foremost, Martin’s first check is about how much time is left on your passport.

“Do you have six months left on your passport or three months if you're going to the European Union?” he asked.

If you are cutting it close, you should check the individual country’s requirements, Martin advises, as the mistake many people make is assuming there is one rule that applies everywhere.

There is one check though which “catches people out” the most, he revealed, and it’s the second one.

“It's the one I get the most emails about - people being turned back from the plane or turned back when they arrive at border control,” he said.

It is all about how old your passport is and has nothing to do with your expiry date.

“You could have more than six months left but your passport could be 10 years old and you can get turned back," he said.

The MoneySavingExpert founder explained how until 2018, if you renewed your passport early and still had time remaining on the old one those extra months could be added onto the new passport.

What that means is that some travellers have a passport with months left until expiry but one that is already more than 10 years old from its issue date.

“People check: ‘Oh, I've got six months left’. They don't check how old their passport is,” he said.

Working it out is simple. Both dates are printed on your passport and Martin's advice is to check both before you travel.

A spokesperson for travel experts Lapland Famille added: "Martin's two check rule is something every traveller should know before they book, not the night before they fly. The issue date is the one that catches people completely off guard because it simply does not occur to most people to check it."

"Both dates are right there on the passport and taking 30 seconds to check them against the entry requirements for a destination could save a holiday from being cancelled before it even begins. If either date is close to the limit, renew early — it is a far easier problem to solve at home than at the departure gate."

Here’s how you can renew your passport

To renew your passport you’ll need:

• Your old passport
• Any valid passports you have from a different country – send either a colour photocopy of every page (including blank ones) or the physical passport

If you want to renew online it will cost you £102 however if you apply by paper application it will cost £115.50.

For an online application you will need:

• A digital photo
• A credit or debit card
• Your passport
• Apply online

According to gov.uk you’ll usually get your passport within three weeks and the processing time starts from when they receive your documents.

However they warn: “It may take longer than three weeks if we need more information, or we need to interview you. We’ll tell you this within three weeks.”