A personal item is the one small bag you can take on a plane for free, in addition to any carry-on, and it has to fit under the seat in front of you. A purse, a small backpack, a laptop bag or a tote all count. Coats, umbrellas, diaper bags and assistive devices often don't count against you, depending on the airline.
Each airline writes its own rule, so the details below come from their own baggage pages. If you're shopping for one bag that can work as your personal item, the Air Pro compression backpack comes in two lengths, and only one of them is personal-item size. More on that further down.
Last checked: October 21, 2026.
What is a personal item on a plane?
A personal item is a small bag that stays at your feet, under the seat in front of you, for the whole flight. You get one. It's separate from the carry-on, which goes in the overhead bin.
American's carry-on page puts it plainly: "You can bring 1 personal item and 1 carry-on bag on board if they meet the requirements." On the low-cost airlines the personal item matters more, because it's often the only free bag on the cheapest fare.
Some airlines give it exact dimensions. Others only say it must fit under the seat. For the numbers airline by airline, see our personal item size by airline chart. This page covers what the term means and what gets counted.
What counts as a personal item? Examples airlines actually list
Here is what five US airlines name as personal items on their own pages, checked October 2026.
| Airline | Personal item examples it names | Publishes a size limit? | Source |
|---|---|---|---|
| American | Purse or small handbag | Yes | American carry-on bags |
| Delta | Purse, briefcase, small backpack, belt bag, fanny pack, camera bag, diaper bag, laptop bag | No, must fit under the seat | Delta carry-on baggage |
| Southwest | Purse (including crossbody bags), briefcase, laptop case, backpack, blanket, small camera | No, must fit under the seat | Southwest carry-on policy |
| Spirit | Purse, small backpack | Yes, handles and wheels included | Spirit bag info |
| Frontier | Purses, small backpacks, laptop bags | Yes, plus a 35 lb weight limit | Frontier bag options |
So the examples are pretty consistent. What changes is how strictly the size is written down.
Is a purse a personal item?
Yes. Every airline in the table names a purse. The catch is that the purse is your personal item. If you also carry a backpack, that's two items, so put the purse inside the backpack before you board.
Does a backpack count as a personal item?
A small one does. Delta, Spirit and Frontier say "small backpack," and Southwest just says "backpack." A 40-liter hiking pack is a different story: it won't fit under a seat, so the airline treats it as a carry-on.
The word "small" isn't defined on Delta's or Southwest's pages. The seat is the test.
Laptop bags and totes
Delta, Southwest and Frontier name laptop bags or cases. None of the five pages uses the word "tote." A tote is judged like any other bag: one item, within the size limit, under the seat. Soft totes slump, which helps them slide in.
What doesn't count against your personal item?
Most airlines let you bring a few things on top of your personal item and carry-on. The list isn't the same everywhere, and that's where people get surprised.
| Airline | Items its page says don't count (checked Oct 2026) |
|---|---|
| American | Diaper bags (1 per child), breast pump, small soft-sided cooler of breast milk, child safety seats, strollers, medical or mobility devices |
| Delta | A jacket and/or umbrella, food or drink bought past security, a bag or box of duty-free items, strollers, wheelchairs, child safety seats, assistive devices such as crutches |
| Southwest | Neck pillows (the only exception the page names) |
| Spirit | Umbrella, camera, infant diaper bag, assistive devices, outer garments (coat, hat, wrap), reading material, food for the flight. Neck pillows only if they fit inside your personal item |
| Frontier | Coats, canes, crutches, portable oxygen concentrators, respiratory devices, assistive devices (listed as exempt from carry-on charges) |
Two details are easy to miss. On Delta, a diaper bag is one of the personal item examples, so it uses up your one item. On American and Spirit it's extra.
And coats. Spirit, Delta and Frontier all exempt them. American's page doesn't mention coats either way, so wearing yours on board is the safe move there.
Personal item vs carry-on: what's the difference?
The short version: a personal item goes under the seat and a carry-on goes overhead. Size and price follow from that.
| Personal item | Carry-on bag | |
|---|---|---|
| Where it goes | Under the seat in front of you | Overhead bin |
| How many | 1 | 1 |
| Size example (American) | 18 x 14 x 8 in (45 x 35 x 20 cm) | 22 x 14 x 9 in (56 x 36 x 23 cm), handles and wheels included |
| Typical bags | Purse, small backpack, laptop bag, tote | Roller suitcase, larger travel backpack, duffel |
| Cost on the cheapest fare | Free on the airlines we checked | Extra on some basic fares (Spirit's Value fare, for example) |
Which fares include a carry-on is in the by-airline chart, along with every published size.
What does "fits under the seat in front of you" mean?
Delta and Southwest don't publish personal item dimensions. Their rule is the space under the seat, and that space changes from one plane to the next. A bag that slides in on one flight can be tight on the regional jet you connect to.
On airlines that do publish a size, depth is usually what fails. A soft backpack measures 8 inches deep empty. Pack it full, add a water bottle in the side pocket, and it can be 10.
What happens at the gate if your personal item is too big?
It depends on the airline, and not all of them spell it out.
- Frontier says the size of your personal item "will be checked during boarding," and items larger than the allowed size "are subject to an additional charge."
- Spirit counts handles and wheels in the 18 x 14 x 8 limit. Its bag page doesn't list a gate fee for an oversized personal item.
- Delta says a flight attendant or gate agent can check your bag at the gate if it doesn't fit or the bins are full.
- Southwest tells you to check anything too large at the ticket counter before you go to the gate.
On Frontier, a bag that fails the check costs extra at the gate. If you're unsure, decide at home, not in the boarding line.
How to decide if your backpack counts
- Look up your airline's limit in the personal item size chart. If it publishes no size, the seat is the limit.
- Pack the bag the way you'll fly with it, then measure. Include pockets, straps and anything clipped on.
- Check depth twice. It's the number that grows when you pack.
- Count your items. A purse plus a backpack is two.
- Weigh it if you fly Frontier. Its personal item limit is 35 pounds.
- Check your fare. If a carry-on is included, a bag that's a little too big can usually go overhead instead.
Where a compression backpack fits in
The Air Pro is a backpack with a vacuum-seal compartment. You pack clothes, attach the included rechargeable pump to the valve, and the air comes out. The bag's outside size is what the airline measures, so compression helps you fit more inside the same box. It doesn't make a big bag small.
The 17-inch Air Pro measures 17 x 12.6 x 6 to 8 inches, which is within an 18 x 14 x 8 personal item limit based on published dimensions. We haven't tested it in an airline sizer. The 19-inch version is carry-on size. Our guide to fitting a vacuum backpack into 18 x 14 x 8 goes into more detail, and the Spirit personal item guide covers the airline where this matters most.
The downsides are real. Compressed clothes weigh the same, and the bag itself is 3.5 to 4 pounds empty. Linen and some cottons come out creased. You need the pump to reseal for the trip home, and getting one shirt out means opening the whole sealed compartment.
Who this isn't for: if your fare already includes a carry-on and you fly with a roller bag, you don't need a personal item that does extra work. The same goes if you'd rather not deal with a pump, or you mostly fly airlines whose personal item limit is narrower than 12.6 inches.
If you are choosing a new bag for this, our guide to choosing a travel backpack for women over 50 goes through straps, weight and pockets.
FAQ
Can I bring a purse and a backpack as personal items?
Not as two separate personal items. Airlines allow one. Put the purse inside the backpack, or carry the backpack as your carry-on if your fare includes one.
Does a coat count as a personal item?
Not on Spirit, Delta or Frontier, whose pages exempt coats or jackets as of October 2026. American's carry-on page doesn't mention coats, so wear it to be safe.
Does a diaper bag count as a personal item?
On American (one per child) and Spirit, no. Delta lists a diaper bag as a personal item example, so there it uses your one item.
Is a laptop bag a personal item?
Yes. Delta, Southwest and Frontier name laptop bags or laptop cases as personal items. It still has to fit under the seat and within any published size.
Does a neck pillow count as a personal item?
Southwest says neck pillows don't count toward the limit. Spirit allows them only if they fit completely inside your personal item.
If you want one bag that's built around the 18 x 14 x 8 personal item box, compare both sizes on the Air Pro product page. It starts at $149 with the pump included.