Aer Lingus has introduced a new checked baggage fee system that sees some charges jump by as much as 40pc each-way.
The airline has switched from a two to three-tier pricing system, with checked bag charges now differing for 'Near', 'Mid' and 'Far' destinations.
The new charges are year-round, flat fees priced by weight, as opposed to previously contentious "peak" and "off-peak" baggage charges.
Under the new system, 'Near' charges (to the UK, Paris, Amsterdam and Brussels) for 15kg bags will fall from peak rates of €25 to €15 each-way.
However, charges for 15kg bags on 'Mid' destinations like Spain will jump from peak rates of €25 to €35, while 15kg checked bags on 'Far' routes will rise by over 40pc from €35 to €50 for a single flight (see full table of changes below).
For a return flight, the charges would be doubled - meaning a 15kg bag will now cost a whopping €100 to take to the Canaries and back on holidays.
'Near' routes include the UK, Amsterdam, Paris and Brussels. 'Mid' includes many destinations in continental Europe, while 'Far' includes longer flights to destinations such as Corfu, Croatia and the Canary Islands.
Aer Lingus has defended the new baggage pricing structure, which it began to change towards the end of 2016 (the new fees date from March 28), saying that 58pc of short-haul customers travel on its 30 'Near' services, where it says prices have fallen.
"While guests travelling to 'Mid' and 'Far' destinations incur higher baggage fees, guests travelling to 'Near' destinations in fact are paying 40pc less when compared to baggage fees at the same time last year," a spokesperson told Independent.ie Travel.
Comparisons are complicated, however, by the fact that the airline previously charged different fees for travel in peak (summer, Christmas) and off-peak times.
Just this winter, for instance, 15kg bag charges on 'Near' services were a standard €15, which is the same as the new rate - not a 40pc reduction.
Ryanair similarly 'simplified' its checked bag fees last year, with some confusion as to how the new charges differed from previous peak and off-peak rates.
"Irish travellers benefit from some of the most competitive air fares across Europe," the spokesperson continued, whilst also pointing out that Aer Lingus allows up to two pieces of free cabin baggage per passenger.
The airline offers flexi-fares with checked baggage included, too.
"On short-haul we are focused on providing the lowest priced seat, and thereafter customers may choose from a menu of additional extras," it says.
The new fees are valid for bookings made from March 28 onwards, and for any baggage fees paid, after that date, at airports and via its call centre.
Baggage on transatlantic flights has not been affected.