One thing that often catches passengers out when flying on budget airlines is cabin baggage allowances. On busy flights, it's common to see the dreaded bag sizer coming out, and being over just a centimetre can mean you end up paying a massive fee to check your bag at the gate.

To make things even more confusing, cabin bag size allowances change all the time, so even if you're a frequent flyer, you can get caught out. It's always best to check the size of the cabin bag that's included with your ticket just before you go, so you can avoid hassle at the gates.

It's also much cheaper to pay for extra bags when you book your flight, not once you're at the airport, so always make sure you've booked the amount you need in advance.

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Ryanair is notorious for strictly enforcing cabin baggage sizes, and if you're taking a bag on board, you should make sure you get the tape measure out and check the dimensions before you head to the airport.

However, there's good news for Ryanairpassengers: the free underseat bag included in its basic fare can now be slightly larger. Previously, this small bag had to fit in a sizer with the dimensions of 40 x 25 x 20 cm, but since summer 2025 it can now be up to 40 x 30 x 20 cm. These free bags need to fit under the seat in front of you, and usually people bring a handbag, laptop bag, or small rucksack.

Technically, there's no weight limit on these small bags, as long as they fit under the seat, but passengers will need to be able to carry and handle them, and an excessively heavy bag could be noticed by flight attendants.

Passengers can also pay to bring a second cabin bag of up to 55 x 40 x 20cm onboard with them, and this bag has a weight limit of 10KG. Passengers will need to lift this bag into the overhead locker above them, so bear this in mind when packing. If you prefer to check a bag, you can add a 10KG, 20KG, or 23KG bag to the hold. Prices vary depending on route and availability.

Budget airline easyJetis also known for strictly monitoring bag sizes, and you'll see lots of orange sizers around the airport so you can check whether your luggage will fit. However, it's best to measure bags at home when they're packed so you can adjust accordingly.

Everyone who flies with easyJet gets one small underseat cabin bag included in the price. This can be up to 45 x 36 x 20 cm in size, and easyJet states it can't exceed 15KG in weight.

Customers also have the option to book a second cabin bag of 56 x 45 x 25 cm maximum, including handles and wheels. As a bonus, if you book a second bag, you get speedy boarding included. When booking your flight, you also have the option to pay for up to three checked bags of 15KG, 23KG, or a whopping 32KG. Some airports offer a twilight bag drop for passengers on early flights, meaning you can check your luggage the night before heading off and head straight for security in the morning.

Whether you've booked a package holiday with Jet2, or just a flight, cabin baggage allowances are the same. You get a small bag of 40 x 30 x 20cm, which must fit under the seat, and the price also includes a 10KG piece of hand luggage of up to 56cm x 45cm x 25cm. Again, you must ensure measurements include handles, wheels, and other fixtures.

Package holidays include 22KG of checked baggage, but if you've only booked a flight, you can still add a checked bag for a fee. Passengers can buy up to three bags of 22KG in weight, perfect for those who don't like to travel light.

Families travelling with young kidscan also bring a collapsible pushchair, car seat, and/or travel cot free of charge.

British Airways (BA)'s economy basic fare includes a handbag and a cabin bag. The former can be up to 40 x 30 x 15cm in size and needs to easily fit under the seat in front, while cabin bags can be up to 56 x 45 x 25cm in size. However, BAcan only guarantee that the smaller item will be allowed on board. If there's not enough space in the overhead locker, your cabin bag may need to go in the hold.

BA also offers a range of options for checked bags, depending on the flight route you take and which classes are available. Economy with checked bag includes a 23KG bag in the hold, and unlike most airlines, BA put a size restriction on these checked bags of 90 x 75 x 43cm. Those lucky enough to fly business or first class get much bigger allowances.

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If you've booked a flight only on TUI Airways, you'll get a piece of hand luggage of up to 10KG in weight for free, and this can measure up to 55 x 40 x 20 cm. You can also bring a small personal item like a handbag or laptop bag of up to 40 x 30 x 20cm that's placed under the seat in front of you. TUIemphasises that passengers must be able to lift their hand luggage into overhead storage compartments themselves.

Customers can also add a checked bag when booking their flight, with prices depending on the route and availability. However, if you book a package holiday through TUI and are flying with its airline, then 20KG of checked luggage is included. Some holiday types, such as TUI BLUE or cruises, have a 25KG allowance, so it's worth checking your booking confirmation before you go.

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