So, you're planning a trip with Southwest Airlines and want to avoid any last-minute baggage surprises, especially when it comes to your carry-on? Excellent thinking! While Southwest has been known for its generous baggage policies in the past, it's always wise to be clear on the specifics. Let's dive deep into everything you need to know about Southwest Airlines carry-on dimensions and policies, ensuring a smooth and stress-free journey.
How Big Can Your Carry-On Be for Southwest Airlines? A Comprehensive Guide
Southwest Airlines, unlike many other carriers, used to stand out with its "Bags Fly Free" policy for checked luggage. While that's undergone some changes recently, their carry-on policy remains quite straightforward. Understanding these dimensions is crucial to avoid the hassle of gate-checking your bag or, worse, paying unexpected fees.
Step 1: Engage with Your Luggage! Do You Have the Right Stuff?
Before we even get into the numbers, take a good look at your current carry-on bag. Is it a compact weekender, a sleek rollerboard, or something that perhaps resembles a small spaceship? Seriously, having a general idea of your bag's size will help you visualize whether it will fit the specified dimensions. Now, let's get down to the official rules.
Step 2: Understanding the Southwest Carry-On Dimensions (The Golden Rule!)
Southwest Airlines allows each passenger one carry-on bag and one personal item free of charge. The key is knowing the exact measurements for both.
Sub-heading: The Carry-On Bag: Overhead Bin Bound
Your main carry-on bag is destined for the overhead bin. To be accepted, it must not exceed the following dimensions:
Length: 24 inches (61 cm)
Width: 16 inches (41 cm)
Height: 10 inches (28 cm)
Important Note: These dimensions include any handles, wheels, or external pockets. Don't just measure the main body of your bag; make sure to account for everything that sticks out! A common mistake is forgetting about those protruding wheels, which can push you over the limit.
Sub-heading: The Personal Item: Under Your Seat Buddy
In addition to your carry-on, you're allowed a personal item. This item is designed to fit under the seat in front of you. The typical dimensions for a personal item are:
Length: 18.5 inches
Width: 8.5 inches
Height: 13.5 inches
Examples of acceptable personal items include:
A purse (including crossbody bags)
A briefcase
A laptop computer case
A small backpack
A camera bag
A blanket or pillow (note: neck pillows generally do not count towards the carry-on limit)
Step 3: The "Fit Test": Why Dimensions Matter
Southwest gate agents are trained to spot oversized bags. If your carry-on appears too large, you might be asked to place it in a sizing bin (often called a "sizer") located near the boarding gate.
Sub-heading: The Sizer: Your Bag's Moment of Truth
If your bag doesn't fit comfortably into the sizer without force, you'll be required to gate-check it. While Southwest has recently started charging for checked bags for many customers (unless you're a Business Select flyer, A-List Preferred, or A-List status holder, or have a co-branded credit card), gate-checking your carry-on can still lead to delays and the inconvenience of waiting at baggage claim. Nobody wants that when they're trying to make a quick exit!
Step 4: What Doesn't Count Towards Your Carry-On Limit?
Southwest makes exceptions for certain items, meaning they do not count against your one carry-on bag plus one personal item limit. These include:
A child restraint device (car seat) for a ticketed child with a reserved seat, or when complimentary, available space exists.
Assistive/mobility devices for individuals with a disability (there's no limit to the number of these devices).
Outer garments or other wearable articles of clothing (e.g., a coat, jacket).
Food for consumption during the flight, provided it's in disposable packaging.
Walking canes or umbrellas.
Diaper bags (when traveling with an infant or small child).
Step 5: Packing Smart: Tips for Maximizing Your Space
Knowing the dimensions is one thing; actually fitting everything you need into that space is another. Here are some pro tips:
Sub-heading: Roll, Don't Fold!
Rolling your clothes tightly can save a surprising amount of space compared to traditional folding. It also helps prevent wrinkles.
Sub-heading: Wear Your Bulkiest Items
If you're bringing a bulky sweater, jacket, or heavy boots, wear them on the plane. This frees up valuable space in your carry-on.
Sub-heading: Utilize Packing Cubes
Packing cubes are a game-changer! They help compress your clothes and keep your bag organized, making it easier to fit everything and find what you need.
Sub-heading: Liquids, Gels, and Aerosols (The TSA 3-1-1 Rule)
Remember the TSA's 3-1-1 rule for carry-on liquids:
Containers must be 3.4 ounces (100 milliliters) or smaller.
All containers must fit into one quart-sized, clear, plastic, zip-top bag.
Each passenger is limited to one such bag. This applies to toiletries, makeup, and any other liquids, gels, or aerosols you plan to bring in your carry-on.
Step 6: Special Considerations: Instruments, Pets, and More
Sub-heading: Traveling with Musical Instruments
If your musical instrument (including its case) meets the carry-on dimensions (24" L x 16" W x 10" H), you can bring it as your carry-on if there's space available in the overhead bin or under the seat. If it exceeds these dimensions but still fits in an overhead bin or under a seat, it may still be carried on if space permits. For larger instruments that don't fit, you might need to purchase an additional seat for them, or check them as baggage (fees and specific size/weight limits apply).
Sub-heading: Traveling with Pets
Southwest allows small, vaccinated domestic cats and dogs in the cabin on domestic flights. Your pet carrier counts as either your personal item or carry-on bag. The carrier must fit under the seat in front of you and generally shouldn't exceed 18.5" L x 13.5" W x 8.5" H. Reservations are required for pets, as there's a limit to how many can be on each flight.
Step 7: The Recent Changes to Checked Baggage (A Quick heads-up)
While this post focuses on carry-on, it's worth noting the recent shift in Southwest's checked baggage policy. As of May 28, 2025, Southwest has ended its long-standing "Bags Fly Free" policy for most travelers. For flights booked or voluntarily changed on or after this date, you can expect to pay:
$35 for your first checked bag.
$45 for your second checked bag.
This makes adhering to carry-on limits even more important if you want to save on baggage fees!
Step 8: Final Checks Before You Fly
Measure your bag: Seriously, do it! Use a tape measure and include wheels and handles.
Weigh your bag: While Southwest doesn't have a weight limit for carry-on bags (only for checked bags), keeping it lighter makes it easier to lift into the overhead bin and ensures you're not struggling.
Pack essentials in your personal item: Keep medications, valuables, and anything you might need during the flight in your personal item, which will be easily accessible under the seat.
Check the latest policies: Airlines can change their policies. Always do a quick check on the official Southwest Airlines website before your flight for the most up-to-date information.
By following these steps, you'll be well-prepared to breeze through the airport with your Southwest Airlines carry-on, ready for your adventure!
FAQs: Southwest Airlines Carry-On & Baggage
How to measure my carry-on bag accurately for Southwest Airlines?
To measure your carry-on accurately, use a tape measure and include all parts of the bag, such as wheels, handles (even when retracted), and any external pockets or protrusions. Measure the length, width, and height at their longest, widest, and highest points.
How to fit more into my Southwest carry-on?
To fit more, roll your clothes tightly instead of folding them, wear your bulkiest items on the plane, and consider using packing cubes to compress and organize your belongings.
How to know if my personal item is the right size for Southwest?
Your personal item should be small enough to fit comfortably under the seat in front of you. While Southwest provides typical dimensions (18.5 x 13.5 x 8.5 inches), the key is that it must fit in that under-seat space without obstructing the aisle or other passengers.
How to handle liquids in my Southwest carry-on?
All liquids, gels, and aerosols in your carry-on must follow the TSA's 3-1-1 rule: containers must be 3.4 ounces (100 milliliters) or less, fit in one quart-sized, clear, plastic, zip-top bag, and each passenger is limited to one such bag.
How to avoid gate-checking my carry-on on Southwest?
To avoid gate-checking, ensure your carry-on strictly adheres to the 24" x 16" x 10" dimensions, including wheels and handles. If it's too large to fit in the sizer, you will be required to gate-check it.
How to travel with a musical instrument on Southwest?
If your musical instrument fits within the standard carry-on dimensions (24" x 16" x 10"), it can be brought as your carry-on. If it's slightly larger but still fits in the overhead bin or under a seat, it may be allowed if space permits. For larger instruments, you might need to purchase an extra seat or check it.
How to bring a pet on a Southwest flight as a carry-on?
Southwest allows small domestic cats and dogs in the cabin in a carrier that fits under the seat (typically max 18.5" L x 13.5" W x 8.5" H). The pet carrier counts as either your carry-on or personal item, and you must make a reservation in advance due to limited pet spaces per flight.
How to know if I'll be charged for checked bags on Southwest now?
For flights booked or voluntarily changed on or after May 28, 2025, most Southwest passengers will be charged $35 for the first checked bag and $45 for the second. Exceptions generally apply to Business Select flyers, A-List Preferred, A-List status holders, and those with a Southwest co-branded credit card.
How to ensure my carry-on fits in the overhead bin?
Pack your carry-on efficiently and ensure it meets the 24" x 16" x 10" dimensions. If it's too full or bulky, it may be difficult to fit in the overhead bin, especially on smaller aircraft or if bins are already crowded.
How to find the most current Southwest Airlines baggage policies?
Always check the official Southwest Airlines website's "Baggage" or "Carryon and Personal Item Policy" section. This is the most reliable source for the latest rules and regulations, as policies can be updated.
