Southwest's carry-on size limits

Southwest allows one free carry-on bag that must fit in the overhead bin. The airline's official size limit is 22 inches long by 14 inches wide by 9 inches deep. This is measured at the bag's widest points, including handles and wheels.

You also get one personal item free — a purse, backpack, laptop bag, or small briefcase that fits under the seat in front of you. There is no official size limit for the personal item, but it must be small enough to fit in that space without blocking the aisle or emergency exits.

Southwest does not charge for either the carry-on or personal item. The airline measures bags at the gate if there is any doubt, and bags that do not fit go into the overhead bin or are checked at no extra cost on Southwest flights (though this may vary if you are connecting to another airline).

Key Takeaways

  • Your carry-on bag can be up to 22 by 14 by 9 inches and goes in the overhead bin at no charge.
  • You also get one personal item free, which must fit under the seat in front of you.
  • If your bag is larger than the limit, Southwest will gate-check it for free on Southwest flights.
  • Wheels, handles, and expandable sections all count toward the 22-by-14-by-9 measurement.
  • Most standard rolling carry-on bags sold in stores meet Southwest's size limit.

How to measure your bag correctly

Measure your bag at its absolute widest point in each direction. If your bag has wheels, measure from the bottom of the wheels to the top. If it has a handle that extends upward, that counts too. Many people measure only the bag itself and forget the wheels add 2 to 3 inches to the length.

If your bag is expandable — meaning the sides zip out to make it bigger — measure it in the expanded position. Southwest's limit applies whether the bag is expanded or not, so if it exceeds 22 by 14 by 9 when expanded, you should not expand it on the plane.

A standard carry-on rolling suitcase from most luggage brands (Samsonite, American Tourister, Away, Calpak) will fit. Duffel bags and soft-sided luggage are often smaller and fit easily. Hardshell suitcases marketed as "carry-on size" almost always meet the limit.

What happens if your bag is too large

If your bag is larger than 22 by 14 by 9 inches, Southwest staff will ask you to check it at the gate. On Southwest flights, this is free — you do not pay a checked bag fee. Your bag will be loaded into the cargo hold and will arrive at your destination with the plane, though it may take a few minutes longer to retrieve.

If you are connecting to another airline after your Southwest flight, that airline's baggage policy takes over. Some partner airlines charge for checked bags, so ask at the gate before your bag is tagged if you are unsure.

The gate agent has the final say on whether a bag fits. If you are worried your bag is borderline, arrive early and ask to have it measured before you board. This gives you time to rearrange items or make other plans if needed.

Packing tips to stay within the limit

Roll your clothes instead of folding them — rolling uses less space and makes it easier to fit more in. Pack heavier items on the bottom and lighter items on top so the bag sits flat in the overhead bin.

Use packing cubes or compression bags to organize items and reduce bulk. Leave the bag slightly under-packed so it is not bulging at the seams; a bag that looks stuffed may not fit even if it technically meets the size limit.

Wear your bulkiest items on the plane instead of packing them. A heavy jacket or boots take up a lot of space in a carry-on, so wear them during travel and pack lighter layers instead.

Personal items and what counts

Your personal item is separate from your carry-on and does not count toward the size limit. A laptop bag, small backpack, purse, or briefcase all work. The only rule is that it must fit under the seat in front of you without blocking the aisle.

Some travelers use their personal item to carry items they want to keep with them — medications, valuables, electronics, documents. Others use it for a light jacket or a book. You can access your personal item during the flight, whereas your carry-on in the overhead bin is not easily reached.

Comparing Southwest to other airlines

Southwest's 22-by-14-by-9 limit is the same as most major U.S. carriers, including Delta, United, and American. Alaska Airlines uses the same limit. Spirit and Frontier have the same official size but are stricter about enforcement and may charge if your bag is even slightly over.

International airlines vary. Many European and Asian carriers have smaller limits — sometimes 21 by 13 by 8 inches or even smaller. If you are flying internationally or connecting through another airline, check that airline's policy before you pack.

Frequently Asked Questions

Can I bring a roller bag and a backpack as my two free items?

Yes. You can bring one carry-on (the roller bag) and one personal item (the backpack). Both are free. The backpack must fit under the seat in front of you, and the roller bag goes in the overhead bin.

Do I have to pay if my bag is too big?

No. If your bag is larger than 22 by 14 by 9 inches, Southwest will gate-check it for free on Southwest flights. You do not pay a checked bag fee. If you are connecting to another airline, that airline's fees may explore.

What if I have a bag that is exactly 22 by 14 by 9 inches?

It should fit, but bags that are exactly at the limit may be tight in the overhead bin, especially if other passengers' bags are already there. A bag that is 21 by 13 by 8 inches or smaller gives you a safety margin.

Can I bring a car seat or stroller as a carry-on?

Car seats and strollers are not counted as carry-on bags. You can bring a car seat and a stroller plus your regular carry-on and personal item. Car seats must be in a seat on the plane; strollers are gate-checked and returned at your destination.

Do soft-sided bags have different size limits than hard-sided bags?

No. The 22-by-14-by-9 limit applies to all bags regardless of material. Soft-sided bags may compress slightly, but Southwest measures them at their full size, so do not count on compression to get you under the limit.