Southwest, the largest domestic carrier in the US, is known for its generous baggage policies: two free checked bags per passenger. Its carry-on policies, meanwhile, are standard: one larger suitcase and a personal item. Here’s what to know about Southwest carry-on size for your next flight.
Southwest Airlines carry-on size: An overview
All Southwest passengers are allowed one bag that goes in the overhead bin and a smaller item that fits under the seat in front of them. The larger bag size limit is 24 x 16 x 10 total inches , including wheels, handles, and attachments. Southwest does not specify a weight limit.
Southwest carry-on bag size for personal items
Southwest carry-on size policies for children’s items
Like most US carriers, Southwest has fairly generous carry-on policies for parents or caregivers traveling with little ones. Strollers and car seats can be checked for free at the check-in counter or at the gate.
In addition, baggage containing a breast pump and/or breast milk may be brought onboard. These items do not count toward the standard carry-on limit. However, Southwest reminds passengers that they might be asked about the nature of the additional carryon bag(s) during their trip.
Southwest policies for children with their own seat
If your child has their own seat, they have the same carry-on allowances as adult passengers. However, if you are using a child restraint system (CRS), their seat counts toward one of those items. Note that car seats are allowed on board, but only in window and middle seats.
Are strollers allowed as carry-on bags on Southwest?
That depends on a couple of factors. First, they must collapse small enough to fit within the maximum dimensions specified above. If it’s a full flight, you may be required to gate-check your stroller – so it’s highly recommended to be prepared for that possibility.
If you are planning to gate check your stroller on Southwest, be sure to get a tag from the gate agent prior to boarding. Amid the craziness of flying with young children, this can be an easy step to forget. But it’s an important one so you can board on time.
What extra items can you bring on board Southwest flights?
Southwest allows passengers to bring extra items on board that do not count toward the carry-on allowance. The following items are neither considered a carry-on bag or smaller personal item:
- assistive/mobility devices such as walking canes
- food in disposable packaging
- child restraint systems (or CRSs, as Southwest refers to them)
- wearable articles of clothing such as coats or wraps
- umbrellas
Carry-on rules for musical instruments on Southwest
If your instrument is too big to fit in an overhead bin or under a seat, you may purchase a seat for it. However, the following conditions must be met:
- It must not block aircraft signage
- It must be placed in the first row in a seat closer to the window than any passenger in the row
- It must fit in the seat and be secured with a seatbelt.
Southwest carry-on FAQs
Still have questions about Southwest carry-on bag size or other concerns? Find all the answers you need below.
Southwest does not specify a weight limit, but you must be able to lift your carry-on bags without assistance.
Yes – in fact, they are only allowed in carry-on luggage, per Federal Aviation Administration regulations. Spare lithium batteries used for portable electronic devices and cigarette lighters must be removed from checked or gate-checked baggage and carried onboard the aircraft. Because of the potential to generate heat and cause a fire, such items are strictly forbidden in checked baggage and must be transported in carry-on baggage only.
Yes, assuming that both fall within Southwest carry-on size dimensions.
Top three Southwest carry-on luggage tips
Southwest has arguably the most generous baggage policy in commercial aviation, with two free checked bags per ticketed passenger. This is great incentive to forgo the overhead bin battle altogether and just bring a personal item for your flight.
Southwest’s major changes to its open seating policy, which will go into effect in 2025, will likely require some adjustment. However, keep in mind that passengers sitting in the front row or exit row must store all carry-on bags in the overhead bin, including their personal items.
If you decide to gate check a stroller or car seat, keep in mind that these items fall under what’s known as a limited release of liability. This is part of the fine print of Southwest’s contract of carriage, and it essentially means that the airline is not responsible if those items are damaged.
Still have questions about Southwest carry-on size?
Luggage policies can be confusing. For an easy way to compare carry-on rules across airlines, check out our carry-on luggage guide. Need help deciding between a carry-on or checked bag? Or perhaps you’re stuck on what to pack? We have plenty of handy tips for that, too. Finally, don’t forget to check what’s allowed in a carry-on before you head to the airport.
⏰ Last update: February 24, 2025 – because staying informed makes travel smoother.
