Last Updated on September 17, 2021
There is no such thing as “airline approved carry-on luggage” in the sense of all the airlines as a group. And for that matter, “TSA-approved carry-ons” don’t exist either or “FAA-approved carry-on luggage”.
A lot of people assume that there is some form of industry-wide standard and either the airlines, the TSA, or the FAA must regulate it and set the sizing rules for the entire industry.
That’s not the case. There is no standard carry-on luggage size making it difficult to own one air travel bag that will be approved by all the airlines.
Instead each individual airline sets their own rules about what size of carry-on they allow.
So a carry-on suitcase approved by Southwest might not be approved by Delta. And hand luggage approved for Delta might not be approved for Spirit or Frontier.
This post will help you find carry-on luggage approved by the airline you are flying with.
Hand Luggage 101
When it comes to hand luggage most airlines allow you to bring two bags. These are called the carry-on and the personal item.
Sometimes people forget about the personal item and think that it’s only a purse. In fact, the personal item size limit actually allows you to bring a lot of extra stuff.
Check this example from the American Airlines rules where the suitcases are illustrated to scale. The personal item here is not a lot smaller than a full-size carry-on.
Some airlines only allow you to bring a personal item and not a carry-on.
Let’s take a look at each of the airlines in the United States and pick out bags that would be approved by that airline as hand luggage.
Remember that all airlines include the wheels and handles when measuring luggage. Luggage manufacturers don’t always include the wheels and handles when telling you the size of the bag. Thanks guys, that’s super helpful.
When shopping for carry-on luggage always read the reviews and try to find someone who has actually measured the bag. That’s often the best way to get the real size of the bag.
Airlines Based In The United States
A carry-on with Alaska can be 22 x 14 x 9 inches or 45 linear inches.
Linear inches is when you sum the 3 dimensions. This means you can steal an inch from one side and add it to the other.
For example, 23 x 14 x 8 inches is also 45 linear inches. However, not all airlines allow you to measure using the linear inches method.
This bag is the perfect size to be approved by Alaska Airlines.
A personal item on Alaska can be 17 x 11 x 9.5 inches. While this bag from boarding blue is slightly too large it’s soft and can be squashed to fit.
You could bring both of these bags on a flight with Alaska Airlines.
The personal item size for American Airlines is 18 x 14 x 8 inches. In addition to that, you can bring a carry-on that can be 22 x 14 x 9 inches. That’s a lot of stuff!
The best way to do this is to bring a flight bag attached to your suitcase.
Allegiant doesn’t allow you to bring a carry-on bag unless you pay extra for it.
The personal item size is 16 x 15 x 7 inches, if you follow that link you’ll see a bunch of bags that might be suitable.
Delta Air Lines
Delta are very mysterious about the size under their seats. You are allowed to bring a bag that fits under the seat but they don’t tell you how much space is under the seat.
Their carry-on can be 22 x 14 x 9 inches.
Frontier doesn’t allow you to bring a carry on bag unless you pay extra for it.
The bag you are allowed to bring, the personal item, can be 18 x 14 x 8 inches. This bag from American Tourister would be approved by Frontier Airlines.
If you do pay extra the size limits for the carry-on you can bring are a generous 24 x 16 x 10 inches. But then you probably don’t own a suitcase that size. They also have a 35 lb weight limit on that bag.
The personal item “must fit under the seat in front”. They don’t tell you how much space is under the seat.
The carry on can be 22 x 14 x 9 inches.
If you buy the cheapest Blue Basic fare you are not permitted to bring a carry-on bag.
The only approved bag in that scenario is a 17 x 13 x 8 bag.
So here is a good bag if you are flying on a JetBlue Blue Basic fare.
If you are not flying on the economy fare you can bring a 22 x 14 x 9 inches carry on with JetBlue.
Southwest have the most generous baggage policies of all the airlines. They allow a carry on to be 24 x 16 x 10 inches but if you buy a carry-on as large at that you probably won’t be able to use it on other airlines.
So it would only be worth shopping for a carry on that size if you flew a lot with Southwest.
This suitcase claims to be the maximum size permitted on Southwest Airlines.
Southwest also allow you to bring a personal item that can be 18.5 x 8.5 x 13.5 inches.
On top of that they don’t charge for checked luggage!
Spirit does not allow you to bring a carry-on bag unless you pay extra. If you want to avoid these fees you need to fit everything in the one personal item that you are allowed to bring.
The approved size of a Spirit personal item is 18 x 14 x 8 inches. You can compare bags of that size on this post.
My favorite rolling suitcase that size is the American Tourister mentioned above. However if you are flying with only an under-seat personal item then a backpack might be more suitable.
Remember because airlines include wheels and handles when measuring luggage anything protruding is costing you packing space.
This backpack is the perfect size for using with Spirit Airlines.
United also allow carry-on bags that can be 22 x 4 x 9 inches.
In addition to that you can bring a personal item that can be 17 x 10 x 9 inches.
You might have noticed that 22 x 14 x 9 inches is almost a de facto standard in the United States outwith the low-cost airlines and Southwest.
Also if you are traveling internationally then it gets more complicated.
You know that saying “birds of a feather flock together”? Something like that applies for carry-on luggage size limits around the world.
You can find trends in different regions where some airlines have adopted a similar size limit.
If you want to check this you can find all the international carry-on size limits on this page.
If you want to buy one carry-on bag that has a good chance of being approved around the world then 21 x 14 x 8 is my recommended size. It won’t work with every single airline but it will get you a long way around the world.
However, if you want to own one bag that you can use to travel around the world then you should really consider a backpack or a duffel bag.
Soft-sided bags can be squeezed to fit if they are not stuffed full. You can even carry a folding luggage trolley if you want wheels.
But rigid suitcases can’t be squeezed to fit in the sizer and it means you really need to get things right for your suitcase to be approved by the airline.
The last thing to say about carry-on luggage on international airlines is that weight limits are extremely common. In Asia the weight limit for carry on luggage are very restrictive. For example the carry-on weight limit for Air China is 11 lbs. I’ve seen empty suitcases that weigh 11 lbs!
If you fly domestically then it makes sense to buy a carry-on bag that is 22 x 14 x 9 inches. In the US that size of bag will be airline compliant luggage for 7 out of 10 airlines.
It would make little sense to buy a large bag for Southwest unless you exclusively fly with Southwest.
Personal item size limits vary a lot more. Low-cost airlines are usually more generous with their personal item size limit.