Travellers who have flights booked with Ryanair in November have been urged to check their departure date.
The budget airline has announced its online check-in process will be down temporarily, which could lead to holidaymakers getting slapped with an unexpected fee before they even board the plane.
The Ryanair website and app is set to undergo maintenance for an 11-hour period, with the outage starting 6pm on November 8 and ending at 5am on November 9.
Passengers have been told to check in ahead of the maintenance work if they are flying during this period - lest they get fined.
Ryanair charges customers £55 for failing to check in online if their flight departs in less than two hours, or £30 for flights to Spain.
An announcement on the Irish airline's website reads: "Due to planned maintenance, Ryanair website / app will be temporarily down from 18.00hrs Tue, 8 – 05.00hrs Wed, 9 Nov.
"Customers who are due to fly during this 11-hour period should check-in online before 18.00hrs on Tue, 8 Nov."
Unfortunately, the fine could leave passengers out of pocket before their holiday even begins. The news comes after a recent report found that two-thirds of Brits admit that they were also caught out by " financial blindspots " while abroad.
The HSBC UK survey found that one in 10 have made purchases abroad in GBP, which is more expensive than local currencies.
On top of this, six in 10 holidaymakers said they incurred fees for cash withdrawals and debit card transactions last time they travelled overseas.
One in four Brits were also found to have gone over-budget by between £100-£300 on their holiday this year.
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