Passengers travelling with Ryanair have until December 1 to comply with the airline’s new baggage rules or face a £25 charge.

The rules were scheduled to come into force on November 1 but a leniency period was introduced amid confusion at the gates. This will last until the end of the month, a Ryanair spokesperson confirmed to Telegraph Travel today.

The change in the carrier’s baggage policy – the second this year – means passengers are only permitted to travel with one small bag (35cm x 20cm x 20cm) free of charge, which must be stored under the seat in front. Those who pay the priority fee (£6 per person each way) can travel with a larger bag (up to 55x40x20cm and no more than 10kg). Travellers can also choose to pay £8 to check a bag of the same size into the hold.

Since its soft launch at the beginning of November thousands of passengers have been let off the £25 charge, with staff told “to take a reasonable approach while customers get used to the new rule”. At London Stansted on the November 1, passengers with baggage that should have earned them a £25 fee were told they would not have to pay this time but would next.

The end of the grace period on November 30 means scores of travellers are likely to face extra charges at the gate in the run-up to Christmas.

Earlier this month Ryanair said its new policy had been a success and that fewer cabin bags had improved punctuality by 11 per cent.

“We’ve received lots of positive feedback from our customers and airports across Europe... our new bag policy has reduced airport security queues and improved the boarding gate experience, with 11 per cent better punctuality, as we eliminated free gate bags and related flight delayed,” said the airline’s Kenny Jacobs.

It remains to be seen how the smooth-running queues at the gate are affected by passengers who breach the rules having to pause to pay £25, while bag sizes are also likely to be scrutinised more closely.

Another problem presented by the rule change is the rise in the number of people purchasing access to the “priority” queue so that they can bring a second cabin bag for £6. On many flights “priority” boarders now make up more than half the passengers.