Ryanair will soon make passengers pay £5 per piece of checked luggage, or £2.50 per bag if it has been registered in advance on the airline’s website - an initiative the budget airline claims will mean only 25 per cent of its passengers losing out financially.

The move means that passengers who wish to travel with bags that weigh over 10kg (the weight limit for bags permitted as hand luggage) must pay the charge. For those who have bags that weigh more than 20kg, there will be an excess baggage fee of £5.50 per kg.

In a measure that has already been brought in without warning, Ryanair has reversed its policy of allowing passengers travelling together to pool their baggage allowance, so that a single heavier bag can no longer be carried between two people.

The move will penalise families with young children in particular, as infants do not have a separate baggage allowance so their belongings must be included in their parents’ allowance.

For passengers travelling with hand luggage only, the new rules could be good news, as those in possession of an EU passport will now be able to check in online at www.ryanair.com, before going to the airport and will be eligible for priority boarding.

Travellers who wish to avoid the fees for checking in luggage on Ryanair flights should make their bookings before March 16, as the charges will only apply to bookings made after that date.

Ryanair claims the move will expedite the check-in process for most passengers, and says it is dropping all fares by nine per cent, or an average of £2.50, so those who travel with hand luggage only, estimated to be 25 per cent of passengers, should pay less. Meanwhile it claims those who travel with checked luggage but register bags in advance (an estimated 50 per cent) will pay the same as before, with the £2.50 luggage fee cancelled out by the £2.50 drop in fares.

Passengers already facing fines

In a move that is confusing passengers, ahead of the new baggage policy that comes into effect for bookings made after March 16, Ryanair has already stopped passengers from pooling their luggage allowance.

Whereas the carrier used to allow passengers booked under the same booking reference to share their combined allowance between them, it has started issuing excess baggage fines to passengers who check in bags that are heavier than the current baggage weight limit of 15kg.

Ryanair customers affected by the new rules include those who were abroad when the baggage rules changed. Times Online reader David Turner flew to Shannon with three others, each couple taking one suitcase between them. This was allowed on the outbound flight but on the return journey, they were charged 60 euros in excess baggage fees because the rules had changed while they were in Shannon.

In another example, Kate Thompson and her partner flew to Venice this month with Ryanair and had to pay £39 to check-in a 22kg suitcase that carried their shared belongings.

'Not a cost-cutting measure'

In response to those who claim it is yet another rigorous cost-saving exercise, Ryanair claims it will lose £100m per year as a result of lowering its fares by 9 per cent.

Chief executive Michael O’Leary claims that by streamlining its service the airline will attract more customers and achieve its aim to double in size over the next five years. This would be a significant feat for a carrier that launched more than 30,000 new flights alone last year – the equivalent of 82 new flights per day.

How other carriers weigh in: check-in baggage allowancesBritish Airways allows 23kg per person, which can be pooled between passengers travelling together as long as no single bag weighs more than 32kg

Both Bmi and Easyjet allow an unlimited number of pieces of baggage that weigh up to a total of 20kg per passenger

Flybe allows check-in baggage of up to 25kg per passenger, but charges £2 per bag for bags registered in advance of check-in, or £4 per bag if it is registered at the airport

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