Ryanair is the go-to airline for many in the UK thanks to its cheap fares, making it possible to head abroad on a low budget.

But while the flights alone may be cheap, passengers do have to be wary of being stung by additional charges for your bags and seats. Ryanair’s bag policy states that all passenger fare types include a small personal bag that can be carried on board, but it must be able to fit under the seat in front of you. If it’s too big, then you can take additional baggage with you – at an extra cost.

As well as forking out on extra bags and picking your own seat, Ryanair passengers face being landed with an additional charge after booking that they may not realise.

The low-cost airline charges passengers a £55 fee to check-in for their flights at the airport. The fee is charged per passenger, so if you’re a family of four you face being charged £220 on the spot at the airport, simply to check-in.

There is a slightly lower charge on flights from Spain, with airport check-in fees coming to £30 per passenger. The airport check-in fee is free for Flexi Plus passengers, but only if flights have been booked through the Ryanair website or app.

It is possible to dodge the £55 charge if you check-in for your flight before arriving at the airport, but you have a limited window in which to do this and, crucially, you have to remember to do it.

Ryanair says online check-in opens 60 days before the scheduled departure time if you’ve paid for an allocated seat, but if you haven’t bought a seat and opted for the free random seat allocation then online check-in opens 24 hours before departure.

The online check-in closes two hours before your flight is due to depart, so passengers need to remember to complete it in this time frame or risk being stung with the £55 airport charge.

Ryanair says: “You must check in online at www.ryanair.com and print or download your boarding pass, unless you have a Flexi Plus ticket, in which case you can check in at the airport for free.

“Unless you have a Plus or Flexi Plus ticket, if you do not check in online more than two hours before the scheduled departure time, you will be charged the airport check-in fee set out in our table of fees. 

“The check-in desks close strictly 40 minutes before the scheduled departure time unless you are notified otherwise before flight departure. If you do not check-in by then you may be denied boarding without refund.”

Passengers who check-in online ahead of arriving at the airport can print copies of their boarding pass, or download it, up to two hours before the scheduled departure time.

Ryanair adds: “Your boarding pass must be printed on a single A4 page or downloaded through our app.”