Direct Answer: What Is the Carry-On Luggage Size for Southwest Airlines?
Southwest Airlines permits each ticketed passenger one carry-on bag plus one personal item free of charge. The maximum exterior dimensions for a Southwest carry-on bag are 24 x 16 x 10 inches (61 x 41 x 28 cm), including wheels, handles, and external bumpers. This allowance is substantially larger than the 22 x 14 x 9 inch limit enforced by American, Delta, and United. Southwest personal items must not exceed 16.25 x 13.5 x 8 inches and must fit under the seat in front of you. Southwest enforces no official weight limit for carry-on luggage, provided you can lift the bag into the overhead bin unaided.
Official source: Confirm the current allowance, including measurements that count wheels, handles, and attachments, in Southwest’s Carryon and Personal Item Policy before departure.
Table of Contents
- Southwest Airlines Baggage Allowance Explained
- Overhead Bin Fit: Boeing 737-700 vs. 737-800 vs. 737 MAX
- Southwest vs. Legacy US Carriers: Size Comparison Matrix
- The Best Carry-On Bags Tested for Southwest Flights
- Underseat Personal Item Guidelines for Southwest
- Boarding Group Tactics: Avoiding Gate Checks on Full Flights
- Frequently Asked Questions
Southwest Airlines Baggage Allowance Explained
Southwest Airlines remains famous for its passenger-friendly baggage allowances. In addition to “Bags Fly Free” (two free checked bags up to 50 lbs each), Southwest grants an unusually generous overhead carry-on volume.
- Maximum Carry-On Dimensions: 24″ L x 16″ W x 10″ H (61 x 41 x 28 cm). This amounts to roughly 63 liters of external volume, giving you roughly 20% more space than standard 22-inch domestic rollers.
- Maximum Personal Item Dimensions: 16.25″ L x 13.5″ W x 8″ H (41 x 34 x 20 cm). Examples include backpacks, briefcases, purses, camera bags, and small laptop cases.
- Weight Restriction: There is no published carry-on weight limit on Southwest flights. The operational rule requires that the passenger must be capable of lifting and stowing the luggage into the overhead bin without flight attendant assistance.
For broader comparisons across all travel styles and bags, explore our master luggage and travel bags hub, our tested rankings of the best carry-on luggage, and our deep dive into the lightest carry-on suitcases for weight-sensitive routes. Business commuters traveling light should also review the best rolling luggage for business travel.
Overhead Bin Fit: Boeing 737-700 vs. 737-800 vs. 737 MAX
Southwest Airlines operates an all-Boeing 737 fleet. However, the overhead bin architecture varies considerably depending on the specific aircraft variant operating your flight:
Southwest Aircraft Fleet Bin Architecture
- Boeing 737-700 (Legacy Pivot Bins): These older cabins feature traditional shallow pivot bins. Suitcases measuring a true 24 inches long must be placed flat on their backs with wheels facing forward. Bags will not fit on their sides (wheels-in book-style), which limits bin capacity to roughly 3 rollaboards per overhead compartment.
- Boeing 737-800 & 737 MAX 8 (Boeing Sky Interior / Space Bins): These modern cabins feature sculpted, deeper drop-down Space Bins. Bags up to 24 inches long slide in vertically on their edges like books. This design accommodates up to six standard roller bags per bin, significantly reducing the likelihood of gate checks.
Southwest vs. Legacy US Carriers: Size Comparison Matrix
| Airline | Max Carry-On Dimensions | Max Personal Item Size | Carry-On Weight Cap |
|---|---|---|---|
| Southwest Airlines | 24 x 16 x 10 in (61 x 41 x 28 cm) | 16.25 x 13.5 x 8 in | None (Must lift unaided) |
| American Airlines | 22 x 14 x 9 in (56 x 36 x 23 cm) | 18 x 14 x 8 in | None |
| Delta Air Lines | 22 x 14 x 9 in (56 x 36 x 23 cm) | Must fit under seat | None (except select Asian hubs) |
| United Airlines | 22 x 14 x 9 in (56 x 36 x 23 cm) | 17 x 10 x 9 in | None |
| Frontier / Spirit | 24 x 16 x 10 in (Paid Carry-On) | 18 x 14 x 8 in | 35–40 lbs max |
Airline allowances, seating configurations, and enforcement practices can change. Always verify the baggage policy for every carrier on your itinerary, particularly when a Southwest flight connects to another airline.
The Best Carry-On Bags Tested for Southwest Flights
Because Southwest permits a 24-inch length, travelers have two distinct gear options: buy a maximized 24-inch roller to gain extra packing capacity, or stick to a universal 22-inch carry-on that transitions smoothly to American, Delta, and United flights.
1. Best Overall Hardshell: Monos Carry-On Pro
The Monos Carry-On Pro measures 22 x 14 x 9 inches and slides effortlessly into all Southwest Boeing 737 overhead bins. Its aerospace-grade polycarbonate shell, silent 360-degree Hinomoto Lisof spinner wheels, and exterior zippered laptop pocket make it ideal for business and casual travelers alike.
2. Best Classic Softside: Travelpro Platinum Elite 21″ Expandable Carry-On
For durability and organization, the Travelpro Platinum Elite 21-Inch is a flight-crew staple. It features high-density nylon fabric with DuraGuard coating, precision magnetic MagnaTrac spinner wheels, and a built-in fold-out suiter for garments.
Deciding between rigid polycarbonate and flexible fabric? Read our full head-to-head comparison of hard shell vs. soft shell luggage to evaluate impact resistance, weight differences, and packing flexibility.
3. Best One-Bag Travel Backpack: Osprey Farpoint 40
If you prefer navigating airports hands-free, the Osprey Farpoint 40 measures 22 x 14 x 9 inches, well within Southwest’s maximum dimensions. Its stowable harness and padded hipbelt transfer load weight to your hips, making it easy to carry heavy laptops and gear.
4. Best Rolling Underseat Personal Item: Travelpro Maxlite 5 Underseat
When you want rolling convenience that fits directly under the Southwest seat, our field-tested Travelpro Maxlite 5 Rolling Underseat fits cleanly into the Southwest 16.25 x 13.5 x 8 inch personal item envelope on both aisle and middle seats.
Underseat Personal Item Guidelines for Southwest
Underseat dimensions on Southwest aircraft vary slightly depending on your seat position:
- Middle Seats: Offer the widest underseat clearance (approximately 18 to 19 inches wide) because there are no aisle struts or window curvature obstacles.
- Aisle Seats: Slightly narrower due to the curved outer seat support post (roughly 15.5 to 16.5 inches wide). Avoid over-stuffing rigid backpacks if you sit on the aisle.
- Window Seats: Impacted by the curved fuselage wall, narrowing floor width slightly.
Ensure your personal item contains your essential electronics, chargers, medications, and liquids bag from our TSA travel items checklist so you have immediate access during flight.
Boarding Group Tactics: Avoiding Gate Checks on Full Flights
Southwest historically utilized an open seating model organized into boarding groups A, B, and C with positions 1 through 60. As Southwest rolls out assigned seating and premium extra-legroom seating across flights, overhead bin priority will increasingly tie to your fare category and assigned boarding group, while the generous 24 x 16 x 10 inch baggage dimensions remain unchanged:
- Group A (Positions 1–60): Guaranteed overhead bin space directly above your seat row on all Boeing 737 aircraft variants.
- Group B (Positions 1–30): Reliable overhead space throughout the cabin, though bins above rows 1 through 10 often fill first.
- Group B (Positions 31–60): Bins in the front and mid-cabin begin filling; look for open space toward the aft cabin as you board.
- Group C: High probability of encountering full overhead compartments on sold-out flights. Flight attendants will initiate complimentary gate-checking for rolling bags at the jet bridge once overhead capacity is reached.
Pro-Tip for Tight Fits: To prevent your suitcase from bulging past Southwest’s 10-inch depth allowance—which invites gate-check scrutiny—use compression packing cubes and organizers to flatten bulky garments and streamline packing geometry.
Frequently Asked Questions
Does Southwest Airlines have luggage sizers at the gate?
Yes. Southwest maintains metal baggage sizers near check-in counters and boarding gates marked 24 x 16 x 10 inches. If gate agents observe a visibly oversized suitcase, they may require you to place the bag into the sizer.
Can a 22x14x9 suitcase fit as a Southwest carry-on?
Yes. A standard 22 x 14 x 9 inch suitcase fits comfortably within Southwest’s 24 x 16 x 10 inch limit. Choosing a 22-inch bag ensures you can fly on Delta, United, and American without buying another suitcase.
Does a backpack count as a personal item or a carry-on on Southwest?
It depends on how you travel. If you bring both a roller suitcase and a backpack, the suitcase goes overhead as your carry-on, and the backpack must fit under the seat as your personal item. If you travel with only one backpack, you can place it in the overhead compartment regardless of size.