The Southwest carry-on size limit is 24 x 16 x 10 inches (61 x 40.5 x 25.5 cm), and wheels, handles and any attachments count toward it. You may also bring one personal item that goes under the seat in front of you, but Southwest publishes no size for it and states no weight limit for either bag. These are the rules as stated by Southwest on its website, checked 19 October 2026.
| Allowance | Size | Weight | Who gets it |
|---|---|---|---|
| Carry-on bag (overhead bin) | 24 x 16 x 10 in (61 x 40.5 x 25.5 cm), wheels, handles and attachments included | No limit stated | One per passenger, with one personal item. The page does not mention fare types. |
| Personal item (under the seat) | No size published | No limit stated | One per passenger, with the carry-on bag |
Southwest carry-on size in inches and cm
Southwest’s carry-on and personal item policy gives the carry-on limit in inches only, as 24 inches long, 16 inches wide and 10 inches high. In centimeters that is about 61 x 40.5 x 25.5 cm (our conversion, rounded to the nearest half centimeter). Southwest’s examples of a carry-on bag are “roller bag, small suitcase”, and the bag goes in the overhead bin.
The size includes everything that sticks out. Southwest says wheels, handles and any attachments count toward these dimensions, so a backpack with a bottle hanging from its side, or a roller bag with chunky wheels, is measured at its widest point.
Southwest personal item size: no figure published
Southwest does not give a size for the personal item. Its page only says the item goes under the seat in front of you, and gives as examples “purse (including crossbody bags), briefcase, laptop case, backpack, pillow (neck pillows do not count toward the carryon limit), blanket, small camera.”
An older figure of 18.5 x 8.5 x 13.5 inches still circulates on some travel sites. It is no longer on Southwest’s page, so do not rely on it. In practice, a personal item for Southwest is judged by where it goes. If your backpack slides under the seat in front of you, it is doing the job Southwest describes.
Southwest carry-on weight: no limit stated
Southwest’s carry-on page states no weight limit for the carry-on bag or the personal item.
What happens if your bag is too big
Southwest asks you to check a bag that is too large before you reach the gate. If your bag is too large to carry on, or you are bringing more than one carry-on or personal item, its page says to “check item(s) at the ticket counter before you head to your departure gate.” It also notes, “If your itinerary includes a partner airline, their carry-on and personal item guidelines may differ.”
How to measure a backpack for the Southwest limit
Measure the bag the way you will fly with it, packed and closed. A soft backpack is thinner empty than full, and depth is usually where it grows.
- Height: from the bottom seam to the top of the grab handle, which counts toward the limit.
- Width: across the widest point, side pockets and anything clipped to them included.
- Depth: front to back at the fullest point, once the bag is packed.
Then compare each figure with 24, 16 and 10 inches. If all three are within the limit, the backpack fits Southwest’s carry-on size.
Backpacks that fit the Southwest carry-on size
Each backpack below is within 24 x 16 x 10 inches on its stated dimensions. These are the bag’s stated dimensions, and a soft bag packed full bulges, so measure it packed before you fly. Inches are rounded to the nearest half inch.
- Our men’s black faux leather laptop backpack that holds a 15.6 inch laptop, 29 x 13 x 43 cm (11.5 x 5 x 17 in), about 29 liters.
- Our 14 inch faux leather laptop backpack, 43 x 32 x 15 cm (17 x 12.5 x 6 in), 22 liters.
- Our men’s vintage faux leather backpack with a laptop pocket, 38 x 34 x 12 cm (15 x 13.5 x 4.5 in), about 20 liters.
- Our men’s faux leather backpack in PU, for a 14 inch laptop, 32 x 14 x 41 cm (12.5 x 5.5 x 16 in), 20 to 35 liters.
- Our genuine cowhide leather backpack for a 16 inch laptop, 43 x 30 x 15 cm (17 x 12 x 6 in), capacity not stated.
For more choice, our carry-on backpacks collection gathers the bags we sell for cabin travel. We do not list any backpack as a Southwest personal item, because Southwest gives no size to check it against.
Southwest carry-on size compared with other US airlines
Southwest’s carry-on limit is the largest in the table below, tied with Frontier’s. Delta, American and JetBlue allow 22 x 14 x 9 inches. These are the figures each airline states on its own website, checked 19 October 2026.
| Airline | Carry-on bag | Personal item |
|---|---|---|
| Southwest | 24 x 16 x 10 in (61 x 40.5 x 25.5 cm) | No size published |
| Delta | 22 x 14 x 9 in (56 x 35 x 23 cm) | No size published |
| American | 22 x 14 x 9 in (56 x 36 x 23 cm) | 18 x 14 x 8 in (45 x 35 x 20 cm) |
| JetBlue | 22 x 14 x 9 in (55.9 x 35.6 x 22.9 cm) | 17 x 13 x 8 in (43.2 x 33 x 20.3 cm) |
| Frontier | 24 x 16 x 10 in (61 x 40.5 x 25.5 cm), up to 35 lb (16 kg) | 18 x 14 x 8 in (45.5 x 35.5 x 20.5 cm) |
| Allegiant | 22 x 16 x 10 in (55 x 40 x 25 cm) | 18 x 14 x 8 in (45 x 35 x 20 cm) |
The centimeters for Delta, American, JetBlue and Allegiant are each airline’s own figures. JetBlue’s are rounded to one decimal, and Allegiant’s are put in the same order as its inches. The centimeters for Southwest and Frontier, and the kilograms, are our conversion, rounded to the nearest half unit. Fare rules differ too. Allegiant charges for its carry-on bag, and Frontier includes it in its Economy, Premium and Business bundles and otherwise sells it as an add-on.
The smallest carry-on box in the table is 22 x 14 x 9 inches. On their stated dimensions, all five backpacks listed above fit a 22 x 14 x 9 in box, since none is over 43 cm on its long side, 34 cm on its middle side or 15 cm deep, within the smallest centimeter figures in the table (55, 35 and 22.9 cm). A soft bag packed full bulges, so measure yours packed, because depth is the figure a full bag is most likely to exceed.
Southwest carry-on FAQ
How strict is Southwest on carry-on size?
Southwest publishes no tolerance above 24 x 16 x 10 inches, so treat that figure, wheels and handles included, as a firm maximum. Its own page advises “Measure carefully before you fly!”, and it asks you to check an oversized bag at the ticket counter rather than at the gate.
Is Southwest still 2 bags free?
Southwest’s checked baggage policy now says “Checked baggage fees apply.” It gives a 50-pound weight limit and sends you to a separate fee page, but it shows no amounts and does not say whether any fare still includes free checked bags, so check the fee for your fare when you book.
What are the new carry-on rules for 2026?
On 19 October 2026, Southwest’s help page allows one carry-on bag of up to 24 x 16 x 10 inches and one personal item that fits under the seat, with no weight limit stated. The visible change is that the page no longer gives a personal item size. Posts claiming that Southwest is moving to smaller “international” carry-on sizes do not match its page on that date.
Can I carry a backpack and a carry-on on Southwest?
Yes. Southwest allows one carry-on bag and one personal item, and a backpack is one of its own examples of a personal item. The backpack goes under the seat in front of you and the carry-on goes in the overhead bin.
Does Southwest have a carry-on weight limit?
No weight limit is stated on Southwest’s carry-on page, for the carry-on bag or the personal item.
What is the Southwest carry-on size in cm?
About 61 x 40.5 x 25.5 cm. Southwest publishes the limit in inches only (24 x 16 x 10), so the centimeters are our conversion.
Sizes checked on Southwest’s website on 19 October 2026. Airlines change their rules, so check your booking before you fly.