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The hidden fees of low-cost airlines (and how to avoid paying them)

Bags, seats, airport check-in, name changes, card surcharges, currency conversion and checkout add-ons: where the real cost of a budget flight hides and how to dodge it.

Updated on 18 September 2026

Two passports with boarding passes resting on a laptop — Photo: Oxana Melis · Unsplash

At a glance

A low-cost fare usually covers your seat on the plane and one small bag. Almost everything else is an extra, and extras cost less when you buy them online while booking.
The most expensive fees come from forgetting something: not checking in online, taking an unpaid wheelie bag to the gate, a wrong name on the ticket.
In the European Union airlines must show you the final price including taxes and unavoidable charges, and optional extras can't be pre-selected. Reading the summary is still your job.
At checkout, watch out for two traps: being charged in your own currency, and offers for insurance, car hire and hotels.

1. Bags: the biggest extra

An open suitcase being packed, with a camera and sunglasses — Photo: Anete Lūsiņa · Unsplash

Luggage is almost always the priciest extra, and the price changes with the route, the date and when you buy it. Sizes, weights and each airline's rules are in our low-cost cabin baggage guide: here we look at how not to overpay.

Don't trust the "from" price: a survey by the British consumer group Which? of nearly 1,500 bag prices at Ryanair, easyJet and Wizz Air found the lowest advertised cabin bag price less than 1% of the time. Check the price on your own flight.
Buy it early, online: it costs more at the airport. At easyJet an unbooked hold bag costs 70 euros (60 pounds) at the bag drop desk, and the same amount is charged at the gate for an unbooked large cabin bag (as of September 2026, check before booking).
Compare priority and hold bags: sometimes a small checked bag costs less than priority boarding with a wheelie bag in the cabin.
Count both directions: bags are charged per flight, so double the price before comparing two options.

2. Your seat

Choosing a seat almost always costs money, but you don't have to do it: skip it and you'll get a seat assigned for free at check-in. Seat prices vary with demand, route and date.

Travelling as a couple or with friends? Ask yourself whether an hour or two side by side is worth the fee, for each of you and on every flight.
Travelling with children? Read the family seating policy. At Ryanair, for example, even with free random allocation children aged 2 to 11 are seated next to an adult on the same booking.
Mind the timing: without a paid seat, Ryanair's online check-in only opens 24 hours before departure and closes 2 hours before. Set a reminder.

3. Check-in and boarding passes

This is the easiest fee to avoid, and one of the most expensive if you forget.

Always check in online: at Ryanair, if you turn up at the airport without having done it, you pay the airport check-in fee, 55 euros (or 55 pounds) per person according to the airline's help centre (as of September 2026, check before booking).
Keep your boarding pass in the app: Ryanair says it doesn't charge for reissuing a boarding pass if you've already checked in online.
Check when the desks close: at Ryanair, from 10 November 2026, airport check-in and bag drop close 60 minutes before departure instead of 40.
Documents and visas: if the airline asks you to verify them in the app, do it before online check-in closes.

4. Changing a name or a date

Basic low-cost fares aren't refundable and every change has a cost, usually per passenger and per flight, plus any fare difference.

Double-check names before paying: they must match your ID. At easyJet fixing a spelling mistake is free, while replacing the passenger entirely costs 73 euros (60 pounds) online (as of September 2026, check before booking).
Use the first 24 hours: Ryanair lets you correct minor date and time mistakes for free within 24 hours of booking, paying only any fare difference.
If the new flight is cheaper, you don't get the difference back: that's Ryanair's rule, and it's worth remembering before you change.
Avoid call centres and desks: the same changes often cost more by phone. Wizz Air, for example, adds a call centre fee on top of the name change fee.
If you already know you might change, consider a flexible fare: it can cost less than a single change.

5. Babies, sports gear and musical instruments

Infants on your lap: they don't get a seat, but there's usually a fixed fee per flight. At Ryanair they get a baby bag and two items of baby equipment, such as a pushchair and a car seat, at no extra cost.
Sports equipment and instruments: bikes, skis, boards and guitars are charged separately if they don't fit your allowance. Add them online: at easyJet the same equipment costs more if you pay at the airport.
Read the rules first: large items go in the hold with weight limits, and some aren't accepted at all, like electric bikes at Ryanair.

6. At checkout

The payment page is where the last surprises pile up. Here's what to look for.

Card surcharges: in the European Union sellers, online ones included, generally can't charge you extra for paying with a consumer credit or debit card. The ban doesn't cover business cards or schemes like American Express or Diners, and outside the EU the rules differ. easyJet, for example, says it doesn't charge card fees.
Insurance, car hire and hotels: in the EU boxes for optional extras can't be pre-ticked, but the offers keep coming at every step. If you already have travel insurance, for example an annual policy or one that comes with your card, don't buy another.
Book on the website or app: bookings and changes made at the airport or by phone can carry extra handling fees.
Compare the final total with other airlines, extras included, before you hit "pay".

7. Currency conversion

If you fly to a country with a different currency, or the website shows prices in a currency that isn't yours, you may be asked "do you want to pay in your own currency?". This is called dynamic currency conversion (DCC) and it usually costs more than your bank's exchange rate.

Choose the local currency, or the one the price is shown in, on websites, card terminals and ATMs: let your bank do the conversion.
Read the mark-up: in the EU whoever offers the conversion must show its cost as a percentage above the European Central Bank's reference rate.
Use a card with no foreign transaction fees if you often travel outside your currency area.

8. After landing: transfers and car hire

Many low-cost airlines use secondary airports, sometimes far from the city. The cheapest flight can turn into the most expensive if the bus or taxi costs as much as the ticket, or if you land when public transport has stopped running.

Before booking, check how to get to the centre, how much it costs and until what time transport runs.
Car hire: read the excess, deposit and fuel rules, and don't get talked into insurance you don't need at the desk. The European Consumer Centre Netherlands advises photographing the car, the fuel gauge and the mileage at pick-up and return.

In short

Decide straight away what you need and add it online while booking.
Travel light and check sizes and rules in the cabin baggage guide.
Skip seat selection if you don't need it, but remember to check in online.
Double-check names and dates before paying.
Pay with a personal card and in the local currency.
Untick insurance and services you don't need.
Factor in the cost of getting from the airport.

And to start from a low price, create a watch on FlyDown: it alerts you when a flight drops below your budget, so whatever you save you can spend at your destination.

Sources

The figures come from the official pages below, checked in September 2026, and may change: always check before booking. FlyDown is not affiliated with the airlines mentioned: trademarks belong to their respective owners.