Budget airline Ryanair has slashed its free-of-charge check in time from four days to just 48 hours.
The new rules come into effect for departures from June 13 but those who have paid an extra £4 for an assigned seat will still be able to check in 60 days in advance.
It means millions of passengers travelling with the Dublin-based carrier may have to search around for internet connections while abroad to download their boarding pass.
Ryanair charges £55 for anyone who turns up to the airport for a flight without a printed out boarding pass or one downloaded to their phone.
Two years ago, customers could check in up to seven days before their flight, which worked well for those on longer breaks as they could download passes for both legs of their trip at the same time.
It then reduced this to four days and now it will be just 48 hours.
News of the check-in changes quickly sparked conversation on Twitter, with passengers calling it 'confusing'.
Kara Newsome tweeted: '@Ryanair I'm confused by your new check in rules. I now have to check in online between 48-2 hours before my flight.
'What happens when I'm on holiday and have no way of getting online or to a printer before my journey?'
Meanwhile, Shane McKinney added: '@Ryanair your new check-in policy is a disgrace.
'Praying on people that aren’t technologically inclined enough to check in for return flights when abroad. Screwing over your own customers AGAIN.'
Ryanair has already contacted passengers who have booked flights and will be impacted by the new check-in rules.
Commenting on the changes, a Ryanair spokesperson told MailOnline Travel: 'Online check-in (for those customers who don’t choose reserved seats) will be available from 48 hours to 2 hours pre-departure for all flights from Wednesday, June 13.
'This is more than double the 24 hour check-in period operated by British Airways, Lufthansa, Norwegian and Iberia. This will give reserve seat customers more time to select their preferred seats prior to departure.'
It means millions of passengers may have to search around for internet connections while abroad to download their boarding pass. Ryanair charges £55 for anyone who turns up to the airport for a flight without one printed out or a pass downloaded to their phone
Although other airlines do have smaller check-in windows - British Airways' is 24 hours and Aer Lingus 30 hours - customers are rarely charged to check-in at the airport and they are also able reserve a desired seat free-of-charge.
It marks another significant change in policy for the airline, who also changed the rules regarding their cabin bag allowance earlier this year.
Customers are now only able to carry a bag no larger than 35cm x 20cm x 20cm on board, with larger bags being placed in the hold free of charge.
If they wish to take an extra piece of hand luggage, they must pay an extra £5 for priority boarding when booking their tickets.