Size
As mentioned, you will be restricted to a certain size of cabin luggage. This can be anywhere from a generous 56 x 45 x 25cm, to 40 x 20 x 25cm, depending on your airline. It will include the handle and the wheels.
Check with your airline before you fly. Some will also limit you to one cabin bag, and others will allow a separate handbag or laptop bag. Also, check whether they will allow you on with a separate duty-free bag – most do, but a few class this as one item of hand luggage.
If you will be shopping at the airport, it could be worth leaving some room in your cabin bag to squeeze that bottle of aftershave/set of novelty fridge magnets in, too.
It is best to try not to push the dimensions, which is why most suitcases will give you a few centimetres leeway. You may not be checked, but if you are, you may have to pay a big fee.
Hand Luggage Restrictions
The cabin bag restrictions for the most popular airlines in the UK are as follows (subject to change so always check directly before you fly):
55 x 40 x 24cm at 10kg as well as personal item at 25 x 33 x 20cm. Regional allowance flights allow 48 x 33 x 20cm
56 x 45 x 25cm at 23kg. Can also take one 40 x 30 x 15cm handbag. Can depend on where you are flying to
56 x 45 x 25cm. No weight restriction but must be able to be lifted into the overhead locker unaided
55 x 38 x 20cm for Economy. First Class and Business Class passengers are allowed an extra briefcase or garment bag
50 x 40 x 25cm at 7kg. Can depend on where you are flying
56 x 45 x 25cm at 10kg, plus one extra small bag such as a handbag
55 x 35 x 25 cm plus one small item at 40 x 30 x 15 cm
38 x 20 x 30cm underseat bag at 10kg. LowFare+ can have additional 55 x 40 x 23cm overhead at 10kg combined. Flex, Premium, PremiumFlex can have this too, but the combined weight of 15kg
56 x 36 x 23cm at 10kg. Can depend on country and class
40 x 20 x 25cm. No weight restrictions. A check-in bag at 40 x 55 x 20cm can be bought for extra
55 x 40 x 20cm at 10kg for both package and flight-only trips
56 x 36 x 23cm at 10kg. You must be able to place it into overhead lockers unaided. Upper-Class passengers can also take another small bag
40 x 30 x 20cm at 10kg. Does not include handles or wheels. Must fit under the seat in front of you. Can also take an additional bag 55 x 40 x 23cm with WIZZ Priority Boarding
Security
Always lock your hand luggage, even if you know it won’t leave your side.
This can be with a padlock and separate key, or with a combination lock. You should ideally look for a lock which is TSA approved (read more about this below).
Most cabin suitcases will come with some form of lock. Those with a lock attached to the case (such as a keypad) are probably the most secure, as the padlock then can’t be cut off or broken and you don’t have to worry about carrying keys.
Wheels
Suitcases (both large and hand-luggage) can have 2 or 4 wheels. Those with 4 wheels are sometimes called spinner cases and are the easiest to move around, as you can keep them upright and to the side of you. This also protects anything in your case.
Suitcases with 2 wheels usually have to be pulled at a tilt, and behind you, which can be harder when it comes to rushing through busy airports. But they do tend to be cheaper and are easier to pull up kerbs and other levels as opposed to lifting them.
Extra Pockets
Inside your cabin case, look for additional pockets which are great for keeping smaller items safe and separate from everything else, whether this is dirty washing, underwear or your essential documents.
Most cabin luggage pieces will have a couple of different pockets, such as a large mesh section in the lid and extra small pockets for more fragile items. Soft-shelled hand suitcases will usually also have outer pockets, which can be good for keeping your passport and boarding pass to hand.