Budget airlinesare an excellent way to see the world for less, but one thing that can catch you out when boarding is cabin baggage allowances. At peak times, it's common to see the dreaded bag sizer coming out as you board, and just a couple of extra centimetres can end up seeing you slapped with a hefty fee.

Annoyingly, cabin bag size allowances vary a lot between airlinesand seemingly change all the time too, so even frequent fliers can get caught out. That's why it's important to check the airline's official website before you fly to ensure you aren't caught out at the boarding gate.

It's much cheaper to buy extra baggage in advance when you're booking your ticket, rather than paying for excess weight at the airport, so make sure you're realistic about what you'll be packing.

We take a look at airlines' individual policies below...

Anyone flying on the budget airline should make sure they measure their luggage before they head to the airport.

Recently, Ryanair offered some good news for passengers; the free underseat bag that is included in its most basic fare level is now allowed to be slightly larger. Previously, it had to be 40 x 25 x 20 cm, but since summer 2025 Ryanairnow allows bags of up to 40 x 30 x 20 cm. This item can be a handbag, backpack, laptop bag, or other item as long as it fits within the dimensions as it goes under the seat in front of you.

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While these small bags don't technically have a weight limit, passengers will need to be able to carry and handle them, and excessively heavy items might be noticed by the flight crew.

For an additional fee, passengers can also bring a second cabin bag of up to 55 x 40 x 20cm onboard with them of up to 10KG in weight. This will need to be lifted into the overhead locker. Checked bags can also be added of 10, 20, or 23KG, with prices varying depending on route and availability. Checked baggage needs to be under 80 X 120 X 120cm in size per item.

EasyJet also tends to strictly monitor onboard bag sizes, and places orange bag sizers around the airport so you can check your luggage will fit. However, it's still important to measure at home in case you need to repack. Ticket prices on easyJetinclude one small underseat cabin bag of up to 45 x 36 x 20 cm in size and 15KG in weight.

Customers can also add a second cabin bag of 56 x 45 x 25 cm maximum, including handles and wheels for a fee, although this cost does also include speedy boarding. Passengers can also pay for up to three checked bags of 15, 23, or 32KG, and these must have a maximum total size under 275cm when you add the length, width, and height. Some easyJet flights offer twilight drop-offs so you can check your luggage the night before an early flight.

Jet2 offers the same cabin baggage allowance for package holiday and flight only customers: a small bag of 40 x 30 x 20cm, which must fit under the seat, and a 10KG piece of hand luggage of up to 56cm x 45cm x 25cm. Package holiday customers with Jet2also get 22KG of checked baggage included in the flight, while flight-only customers can add this option for an additional fee. Passengers can buy up to three checked bags of up to 22KG if they don't like to pack light.

British Airways (BA) is a little more complicated as it has many different ticket types. You can use its baggage calculatorto find your precise allowance. Those flying on a basic economy fare usually get a small bag and a cabin bag included in the price. The smaller bag can be up to 40 x 30 x 15cm and its guaranteed this will be allowed onboard with you. The cabin bag can be up to 56 x 45 x 25cm, but if overhead locker space runs out, it may need to go into the hold. Make sure your essentials for the flight and passport are in your smaller bag.

Checked bags also vary depending on route and class. Economy with checked bag fares include a 23KG piece of hold luggage up to 90 x 75 x 43cm, and business and first class passengers get much bigger allowances.

Flight-only passengers with TUI get a 10KG piece of hand luggage included in the price of up to 55 x 40 x 20 cm, plus a small personal item like a laptop bag or handbag of up to 40 x 30 x 20cm TUI emphasises that passengers must be able to lift their hand luggage into overhead storage compartments themselves.

Checked bags can be bought while booking the flight, and those booking package holidays with TUIthat fly with its airline get 20KG of checked baggage included. TUI BLUE and cruise customers can get 25KG allowances, so its worth checking your booking confirmation to see if you get this perk.

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