Budget airlines have spent twenty years perfecting the art of the hidden fee. Baggage is their masterclass. Ryanair, EasyJet, Wizz Air, and their cousins have trained us to expect a £5 flight and a £40 baggage surcharge. What they don’t advertise is that the rules change depending on which metric benefits them most.
Weight versus dimensions: the scam that works
Here’s the thing airlines won’t clearly explain: most budget carriers have a weight limit, but dimensions matter too. A 10kg bag that measures 56 x 45 x 25cm is technically under weight but exceeds the size allowance on Ryanair’s cabin bag policy. The airline can reject it at the gate and charge you £40 to check it instead. They’ve also recently tightened restrictions further: only a personal item (max 40 x 20 x 25cm) is free; a regular cabin bag now costs extra on their cheapest fares.
Wizz Air plays the same game. Their basic fare allows only a 40 x 30 x 20cm personal bag for free. Anything larger, even if it’s 5kg, costs £15 to £25. EasyJet is slightly more generous with cabin bags, but they can and do weigh them at the gate.
What they actually measure
Airlines measure both, but apply whichever rule hurts you more. A soft bag that looks small might crush under its own weight. A rigid cabin case with wheels takes up disproportionate space. In practice, low-cost carriers prioritise dimensions for cabin bags (because overhead bins fill fast and they can charge £40 to gate-check) and weight for checked luggage.
The detail that catches travellers: most people overestimate what their bag weighs. A full cabin suitcase easily hits 8kg. Add shoes, a laptop, and toiletries, and you’re at 10kg. EasyJet’s free checked baggage starts at 15kg. Ryanair’s first checked bag is free only on paid fares; on their absolute cheapest tickets, both checked bags cost money.
How to avoid the fee
Use soft-sided backpacks or duffel bags for cabin luggage. Rigid cases are rigid, and airlines know it. Stick to 7kg maximum for anything you carry on. Buy a digital scale; they cost £8 and eliminate guesswork at the airport. Weigh your packed bag at home before you leave.
Check the airline’s current policy the day before you fly. Ryanair changed its baggage rules three times in 2026 alone. Book fares that include a checked bag if you need one; it’s often cheaper than paying à la carte. And if you’re flying with multiple bags, use the airline’s bag measurement tool, not your eyes.
The best defence is to know the exact rules before you arrive at the airport. Airlines count on confusion and time pressure. Don’t give it to them.
