Hidden Fees on Budget Airlines: What to Watch
The headline fare is rarely the full price. These are the fees that most commonly catch travellers out — and how to avoid them.
Budget airlines are built around a model called "unbundling": the base fare covers only the seat and a tiny underseat bag. Everything else — overhead cabin bag, hold luggage, seat selection, airport check-in, priority boarding, food, and sometimes even payment — is priced separately.
This is not inherently bad. If you travel light and know the rules, you pay less. The problem is that most passengers do not read the rules until they are at the airport facing a surprise charge.
The most expensive fees
Oversized cabin bag
Every major budget airline specifies a maximum free cabin bag size. Ryanair's is 40 x 20 x 25 cm — small enough that a standard 20-litre daypack barely fits. Anything larger requires either a Priority boarding add-on (Ryanair, ~£8 online) or triggers a gate charge (Ryanair, €/£25 at the gate). easyJet, Wizz Air, and Transavia have similar policies with slightly different dimensions.
Avoid this: measure your bag against the airline's sizer before you travel. A cheap luggage scale and a tape measure save significant money.
Airport check-in fee
Ryanair charges up to £55 for checking in at the airport rather than online. This is their most notorious fee. Online check-in is free and opens 60 days before departure. There is no reason to pay this — add it to your calendar and check in online the day the window opens.
Hold luggage not booked at the time of flight purchase
All budget airlines increase the price of hold luggage significantly if it is added after purchase, particularly in the 48 hours before departure. Adding a 20 kg hold bag on Ryanair at the airport costs roughly three to four times what it costs to add at the time of booking. Always decide whether you need hold luggage before you complete the purchase.
Seat selection
Budget airlines assign seats randomly if you do not pay for selection. On a short flight, a random seat is fine. On a longer flight (3+ hours) or if you are travelling with others you want to sit next to, selection fees add up: typically £3–12 per seat per flight segment.
For families: airlines are legally required to seat children next to a parent or guardian at no extra cost on EU flights. Invoking this at check-in usually works, though it may mean seats near the back.
Payment surcharges
Some budget airlines (and many third-party booking sites) add a fee for credit card payments. Always check the fee before selecting your payment method. Debit cards are typically free; Amex often incurs a surcharge.
The total cost calculation
Before clicking "book now" on a budget airline, add:
- Base fare
- Cabin bag fee (if your bag exceeds the free allowance)
- Hold luggage (if needed)
- Seat selection (if needed)
- Any payment fee
Compare this total against the equivalent full-service carrier price. On some routes, a no-frills booking on a full-service airline (a basic economy ticket on BA or KLM, for example) can come out cheaper than a budget carrier once all extras are included — and includes a proper cabin bag allowance.