Southwest's checked bag policy: two bags fly free, then you pay

Southwest Airlines allows your first two checked bags to fly at no charge. After that, each additional bag costs $35 on domestic flights and $100 on international flights. This is different from most other major U.S. carriers, which charge for the first checked bag. The policy applies whether you book directly with Southwest or through a travel site.

The free bags must meet Southwest's size and weight limits: 62 inches total (length plus width plus height) and 50 pounds each. Bags that exceed these limits cost $75 per bag on top of any other fees. If you're traveling with sports equipment, musical instruments, or other oversized items, those rules are separate and often cost more.

Key Takeaways

  • Your first two checked bags fly free on Southwest, but any bags after that cost $35 per bag on domestic flights.
  • Each checked bag must weigh no more than 50 pounds and measure no more than 62 inches total (length plus width plus height).
  • Oversized or overweight bags cost $75 each, charged in addition to any other fees.
  • You can pay for extra checked bags when you book your flight or at the airport, though paying ahead of time is faster.

How to pay for extra checked bags before your flight

If you know you'll need more than two checked bags, you can add them when you book your ticket on Southwest's website or mobile app. Log into your reservation, select "Bags" from the menu, and choose how many additional bags you want to check. You'll see the cost right away and can pay by credit card or debit card.

Paying ahead is simpler than waiting until the airport, because you won't have to stand in line at the ticket counter to add bags. You'll also get a receipt and confirmation number, which you can show at the gate if there's any question about your bags.

Paying for extra bags at the airport

If you didn't pay ahead and need to check a third bag (or more), go to the Southwest ticket counter before you check in. Tell the agent you want to add checked bags, and they'll calculate the fee based on how many bags you're adding and where you're flying. You can pay with a credit card, debit card, or cash.

The process usually takes a few minutes, but it's slower than paying online ahead of time. If you're close to your departure time, this delay can be stressful. That's why Southwest recommends paying for extra bags when you book.

What counts as a checked bag versus a carry-on

A checked bag is any bag you hand to an agent at the ticket counter or drop into a baggage chute. It goes into the cargo hold of the plane and comes out at your destination on the baggage carousel. Your first two checked bags are free; anything beyond that costs money.

A carry-on bag is something you bring onto the plane with you. Southwest lets you bring one personal item (purse, backpack, laptop bag) and one roller bag or suitcase into the cabin at no charge. These don't count toward your two free checked bags. Many people use carry-ons to avoid checked bag fees entirely, though carry-on space is limited and bags must fit in the overhead bin.

Oversized and overweight bag fees

If a checked bag weighs more than 50 pounds or measures more than 62 inches total, Southwest charges $75 per bag. This fee is separate from the charge for a third or fourth checked bag. So if you're checking a fourth bag that's also overweight, you'd pay $35 for it being a fourth bag plus $75 for being overweight — $110 total.

To measure your bag, add the length, width, and height together. A standard rolling suitcase is usually around 28 inches long, 20 inches wide, and 12 inches deep, which adds up to 60 inches — within the limit. But a larger suitcase or a bag packed very full can easily exceed 62 inches.

Special items with their own fees

Sports equipment, musical instruments, and other special items have separate rules. A golf bag, surfboard, or bicycle can be checked, but Southwest charges $75 per item in addition to your regular checked bag allowance. A musical instrument that fits in a standard hard case may be allowed as a carry-on at no charge, but larger instruments or multiple cases are treated as checked bags.

If you're traveling with any item that's not a standard suitcase, check Southwest's website or call their reservations line before you book. The fees and rules vary by item type, and knowing ahead of time prevents surprises at the airport.

How the free bag policy works for connecting flights

If you're flying Southwest with a connection, your checked bags are included in your free allowance for the entire trip, not per flight. So if you fly from Denver to Dallas and then Dallas to Miami on the same ticket, you still get two free checked bags for the whole journey. The bags are transferred automatically between flights.

If you're booking two separate tickets — one from Denver to Dallas and another from Dallas to Miami — each ticket comes with its own two free checked bags. This is one reason why booking a connecting flight on a single ticket is often cheaper than buying two separate tickets.

Frequently Asked Questions

Do I have to check bags, or can I just use a carry-on?

You can travel with just a carry-on at no charge. Southwest allows one personal item and one roller bag in the cabin. If you can fit everything you need into those two bags, you won't pay any bag fees. Many people do this to avoid checked bag costs and baggage claim delays.

What if my bag is slightly over the weight or size limit?

Southwest's agents have some discretion, but the official rule is 50 pounds and 62 inches total. If your bag is close to the limit, the agent may weigh or measure it at the counter. If it's over, you'll be charged the $75 overweight or oversized fee. Packing lighter or redistributing weight to another bag is your best option if you're near the limit.

Can I buy extra checked bags for someone else traveling with me?

Yes. When you book your reservation, you can add bags for any passenger on your ticket. Just select the passenger's name and add the bags you want to pay for. This is useful if you're traveling as a family and one person needs more luggage than others.

Do I get a refund if I don't use the extra bags I paid for?

No. Once you've paid for an extra checked bag, that charge is non-refundable. You can use it on a future Southwest flight on the same ticket, but you can't get your money back if you decide not to check it.

What happens if I show up with more bags than I paid for?

You'll be charged the applicable fee at the ticket counter. If you paid for three checked bags but show up with four, you'll owe $35 for the fourth bag (or $75 if it's oversized). It's always cheaper to pay ahead than to add bags at the airport.