MARTIN Lewis has warned Brits heading abroad this summer to check their passports - or they may end up missing their holiday entirely.
The expert gave the advice while appearing on ITV's This Morning show.
He said that anyone who fails to follow the 10-year passport rule could be allowed on their flight - but forced to get on the next one back.
Martin explained: "You also need to check that your passport is not over 10 years old on the date that you enter.
"You used to be able when you renewed your passport to take what you had left on your old passport and add it to your new one so you got more than 10 years.
"But now many countries will not let you in if your passport is older than 10 years."
"This is not a small thing.
"People do their flight and then get sent back, they get sent back and you can't travel.
"I know someone it happened to in Dubai because of the 10 year rule."
The new rules have been in place for years, but still catch as many as 10,000 travellers out a year.
Since leaving the EU, passports can no longer more than 10 years old, with previous rules allowing you to roll up to nine months over from your previous document.
This means your expiry date may not be correct, and you should instead check your start date, and add 10 years to it to avoid falling victim.
And with European destinations requiring at least three months left on your passport, this has caused a number of holidaymakers to miss holidays or pay hundreds of pounds extra.
One Brit was forced to miss four days of her Greek holiday as well as shelling out £300 for a new passport and flights.
She explained on TikTok: "I got declined to get on the flight because my passport was two days out of date from being 10 years old."
And last year, teacher Rosi Simpson was banned from her flight to Paris due to having "no idea" about the rule.
Other passport rules
The Sun's Travel Editor Lisa Minot has explained exactly what Brits need to know.
She said: "In order to travel to the EU, all passports must be no more than 10 years old on the day you arrive in your European destination.
"And you'll need at least three months on your passport on the day you head back to the UK.
"Figures have shown up to 100,000 holidaymakers a year face being turned away at airports if their passport is more than 10 years old.
"The 10-year rule only applies to countries in the European Union but every country may have different rules on what is accepted.
"Some countries like South Africa, for example, insist you have at least six months left on your passport when you travel and a full clear page."
Here's another Martin Lewis holiday hack, with one woman saving £354.
New rules being introduced later this year will also scrap the requirement to have passports stamped when travelling to and from Europe.
The Entry/Exit system (EES) is to be rolled out from October 7, with stamps being replaced with fingerprint and facial checks.
Until the new rules are introduced, Brits still need to get their passports stamped on both exit and entry when travelling to Europe.
This is because, since leaving the EU, UK travellers can only stay in Europe for 90 days within an 180 day period.
Travellers who don’t get an exit stamp when returning from their holiday could see them banned from entering Europe.
This is because there is no evidence of leaving the country, meaning you could be seen as overstaying the 90 days.