Last Updated on July 28, 2026 by Daniel Globe
Southwest Airlines lets you bring one carry-on bag and one personal item on every flight at no extra charge. Many musical instruments, diaper bags, and medical items also travel in the cabin without taking away from your standard luggage allowance. Understanding the exact 24” x 16” x 10” carry-on size limit, packing smart, and knowing TSA guidelines will help you breeze through security and avoid any boarding gate delays.
Quick Answer
Southwest’s carry-on size limit is 24″ x 16″ x 10″ (including wheels and handles) with no published weight limit, plus one free personal item up to about 16.25″ x 13.5″ x 8″ that fits under the seat in front of you. Both items fly free on every fare class, and Southwest continues to include two free checked bags per passenger.
Note: Southwest Airlines transitioned to assigned seating on January 27, 2026. However, its generous carry-on allowances (one carry-on plus one personal item) and signature two free checked bags policy remain fully intact.
At a Glance: Southwest Carry-On Policy
| Carry-On Size Limit | 24″ L x 16″ W x 10″ H (including wheels & handles) |
| Personal Item Size Limit | Approx. 16.25″ L x 13.5″ W x 8″ H (must fit under seat) |
| Weight Limit | No weight restriction (must lift into bin unassisted) |
| Included Baggage Cost | Free (1 Carry-On + 1 Personal Item + 2 Checked Bags) |
Southwest Carry-On Size Rules
Southwest Airlines allows every ticketed passenger to bring one carry-on bag into the aircraft cabin. According to official Southwest Airlines baggage guidelines, your primary carry-on must not exceed 24 inches long, 16 inches wide, and 10 inches high.
These dimension limits include all external features such as wheels, handles, side pockets, and straps. Always measure your bag when it is fully packed, as bulging pockets can push an otherwise compliant suitcase over the maximum dimensions.
Key Takeaways
- Carry-on max dimensions: 24″ x 16″ x 10″, including wheels and handles — with no published weight limit.
- Personal item max dimensions: Approximately 16.25″ x 13.5″ x 8″, which must fit completely under the seat ahead.
- Free baggage allowances: One carry-on bag, one personal item, and two checked bags fly free on all fares.
- Family exemptions: Strollers, car seats, diaper bags, and breast pumps travel free without counting toward your limit.
- Musical instruments: Instruments fitting carry-on dimensions fly in cabin overhead bins; larger instruments may require purchasing a seat.
Southwest has **no official weight limit** for carry-on luggage. However, you must be physically able to hoist your bag into the overhead storage bin without flight attendant assistance. If your bag exceeds the dimensional limits, airport agents will ask you to check it at the ticket counter or departure gate.
What Counts as a Southwest Personal Item?
In addition to your main carry-on bag, Southwest lets you bring one smaller **personal item** free of charge. Your personal item must be stored beneath the seat directly in front of you during takeoff and landing.
Common examples of approved personal items include:
- Purses, totes, and handbags
- Briefcases and messenger bags
- Laptop computers in protective sleeves or cases
- Small backpacks or daypacks
While Southwest does not state exact dimensions for personal items on every ticket confirmation, its standard airport sizers accommodate bags up to **16.25” x 13.5” x 8”**. If you consolidate a smaller purse inside a backpack, Southwest counts it as a single personal item. Outerwear coats, neck pillows, reading material, and food purchased inside the airport terminal after security checkpoints do not count toward your allowance.
“Unlike most major U.S. carriers that charge extra for overhead carry-on bags or basic economy fares, Southwest includes a full carry-on bag and personal item free on every single ticket.”
TSA Liquid Rules & Electronics in Southwest Carry-Ons
Packing your carry-on requires following Federal Transportation Security Administration (TSA screening guidelines) alongside Southwest’s rules:
- TSA 3-1-1 Liquids Rule: All liquids, gels, pastes, aerosols, and creams in your carry-on must be in containers of 3.4 ounces (100 milliliters) or smaller. All containers must fit inside one quart-sized, clear, plastic zip-top bag.
- Portable Chargers & Power Banks: Spare lithium-ion batteries, external battery power banks, and e-cigarettes/vapes are strictly prohibited in checked luggage due to fire hazards. They must remain in your carry-on bag or personal item in the cabin.
- Laptops & Large Electronics: Laptops, tablets, and handheld gaming consoles must be removed from your carry-on bag during standard TSA checkpoint screening unless you have TSA PreCheck.
Can You Bring a Musical Instrument on Southwest?
Yes—you can bring a musical instrument on Southwest as a carry-on or personal item as long as it fits within standard dimension limits (24” x 16” x 10”) or can be safely stowed in an overhead bin or under a seat. Many instruments—such as violins, flutes, ukuleles, and small guitars—travel comfortably in the main cabin.
| Instrument | Usually Fits Carry-On? | Recommended Protection & Rule |
|---|---|---|
| Violin / Viola | Yes | Use a heavy-duty hard shell case |
| Acoustic Guitar | Sometimes | Measure case exterior carefully; board early |
| Keyboards / Cello | No | Requires purchasing an extra cabin seat |
If your instrument exceeds carry-on dimensions but is too fragile to check, you can purchase a separate ticketed seat for the instrument. Under FAA regulations, instruments occupying a purchased seat must be placed in a window seat and secured properly with a seatbelt.
Pro Tip: Boarding early gives you the best opportunity to secure overhead bin space for larger instrument cases. Under Southwest’s assigned seating system, review your assigned boarding group early to plan your boarding timeline.
Southwest Carry-On Rules for Kids & Families
Family travel on Southwest is straightforward thanks to generous exemptions for infant and child equipment according to Southwest’s traveling with children policy:
- Ticketed Children: Children traveling on their own purchased seat receive the full standard allowance: one carry-on bag and one personal item.
- Strollers & Car Seats: Each family can check one stroller and one FAA-approved child restraint system (car seat) free of charge at the curb, ticket counter, or gate.
- Diaper Bags: One diaper bag per child traveling with an adult flies free and does not count against the adult’s personal item or carry-on limit.
- Breast Pumps & Milk: Breast pumps, breast milk, and cooling ice packs are treated as medical necessities and fly free without reducing your luggage allowance.
Medical Devices & Mobility Aids Allowance
Southwest permits passengers with medical conditions to bring necessary medical equipment onboard at no extra charge:
- CPAP Machines & Respirators: CPAP machines, oxygen concentrators (POCs), and sleep apnea equipment do not count toward your carry-on or personal item limit under FAA rules.
- Mobility Devices: Canes, crutches, walkers, and folded wheelchairs can be stowed in overhead bins or designated coat closets on a first-come, first-served basis.
- Prescription Medication: Always pack essential daily medications and medical documentation in your personal item under the seat so they remain accessible during flight delays.
Extra Items Southwest Lets You Bring Onboard
Southwest allows several supplementary personal items onboard that do not count toward your 1 carry-on + 1 personal item restriction:
- Assistive walking devices (canes, crutches, or braces)
- Outerwear layers including coats, jackets, wraps, and hats
- Food and non-alcoholic beverages purchased inside the airport after security
- FAA-approved child restraint systems (car seats) when a seat was purchased for the infant
- Diaper bags, breast pumps, and associated breast milk storage bags
How to Pack a Southwest Carry-On Efficiently
To maximize every inch of space in your 24″ x 16″ x 10″ carry-on bag:
- Roll, Don’t Fold: Tight rolling reduces fabric bulk and prevents deep clothing creases.
- Use Compression Cubes: Packing cubes organize garments into clean rectangular blocks that fit structured luggage frames.
- Distribute Heavy Items Low: Position footwear and heavy toiletry bags near the wheel base for better rolling balance.
- Keep Liquids Accessible: Place your TSA 3-1-1 clear liquids bag near the top opening of your personal item for fast removal at security.
What Happens If Your Carry-On Is Oversized?
If your bag exceeds the 24” x 16” x 10” size limit, gate agents will require you to gate-check it before boarding.
When a bag is gate-checked on Southwest, agents place a claim tag on your luggage and send it to the cargo hold. You will collect your bag at the airport baggage claim carousel upon arrival at your final destination.
Warning: Lithium power banks, spare batteries, electronic cigarettes, and medication must ALWAYS be removed from gate-checked luggage and brought into the passenger cabin.
Gate-checking an oversized carry-on bag on Southwest is complimentary because every passenger receives two free checked bags. However, checking the bag prevents access to your personal items midflight.
Southwest Carry-On Tips for Easy Boarding
- Measure at Home: Measure length, width, and height with pockets packed full before heading to the airport.
- Keep Valuables Under Seat: Store passports, keys, tablets, medications, and jewelry inside your personal item so they remain with you if overhead space runs out.
- Choose Flexible Bags: Soft-sided duffel bags or expandable backpacks compress easily into tight overhead bin spaces compared to rigid hard-shell suitcases.
Frequently Asked Questions
What are the carry-on luggage size limits for Southwest Airlines?
Southwest allows one carry-on bag measuring up to 24” x 16” x 10” (including wheels and handles) with no weight limit, plus one personal item (such as a purse, laptop bag, or small backpack) up to 16.25” x 13.5” x 8” that fits under the seat ahead.
What is Southwest’s senior discount policy?
Southwest offers senior fares on select flights for passengers aged 65 and older. Senior fare availability varies by route and date. You can compare senior fares directly on Southwest.0com or by calling Southwest customer service.
What is the 10-minute rule for Southwest?
Southwest requires passengers to be present at the departure gate at least 10 minutes prior to scheduled flight departure. If you are not at the gate 10 minutes before departure, your reserved seat may be released to standby passengers.
What are the carry-on rules for Southwest in 2026?
In 2026, Southwest continues to offer one free carry-on bag (24″ x 16″ x 10″) and one free personal item (approx. 16.25″ x 13.5″ x 8″) on every fare class, alongside two free checked bags. While Southwest transitioned to assigned seating on January 27, 2026, carry-on dimension rules have not changed.
Conclusion
Keeping your Southwest baggage experience smooth comes down to simple preparation. By checking your bag dimensions against the 24” x 16” x 10” limit before leaving home, selecting an under-seat personal item, and adhering to TSA liquid and battery regulations, you can pass through security effortlessly. With free carry-on allowances and complimentary checked bags included on every ticket, Southwest remains one of the most traveler-friendly airlines in North America.
Sources
- Southwest Airlines — Carry-On Baggage Policy — Official dimensions and baggage restrictions
- TSA Security Screening — What Can I Bring? — TSA liquid 3-1-1 rules, batteries, and prohibited items
- Southwest Airlines — Traveling with Children — Stroller, car seat, and diaper bag guidelines
- Southwest Airlines — Medical Equipment & Assistive Devices — CPAP machines and mobility device rules
