Southwest Airlines fees and trap map

IATA: WN
Verdict

Southwest still matters because free checked bags can reset the math, but the newer fare structure means travelers should stop treating old Southwest assumptions as universal truth.

Fast read: The 2-Bag Weight Split: You get 2 free bags. Pack a light foldable duffel so you can split a 51 lb bag into two ~26 lb bags at the kiosk and avoid the $100+ overweight fee.

What drives the fees

Southwest is the benchmark airline for bag value, yet its newer fare structure means users still need to read the fine print.

Main stack to watch

You are trading bag savings against fare-family differences, seating or boarding changes, and same-day flexibility rules.

Best next tool

Southwest works as a benchmark airline users should compare against before paying annual fees elsewhere just to claw back bag costs.

What matters most here

This is a benchmark page now

Southwest helps users answer whether another airline's low fare is actually low once a normal bag enters the trip.

Compare bag economics
What matters most here

The old free-bag story is not the whole story

Southwest now needs closer reading by fare family and booking timing, which makes the airline strategically more interesting than its reputation suggests.

See fare flexibility
What matters most here

Seat and boarding changes are the new friction zone

As Southwest becomes more segmented, users need to compare it less as mythology and more as an all-in product.

Inspect seat pressure
First bag pressure point
0.00 USD

1st checked bag: free (applies to travel booked and ticketed before May 28, 2025)

Carry-on policy
0.00 USD

Carryon + personal item included: (a) one carryon bag not exceeding 10 x 16 x 24 inches; and (b) one smaller personal item stowable under a seat or in an overhead compartment

Seat upsell signal
0.00 USD

No seat selection with Basic fares; a Standard seat will be assigned at check-in (flights departing on or after January 27, 2026). Until then, Southwest uses open seating

Change flexibility
0.00 USD

No cancel fees (all fare types eligible for cancellations without a fee); failure to cancel at least 10 minutes prior to scheduled departure may result in forfeited travel funds

How to beat Southwest Airlines fees

Go from fee table to traveler strategy: traps, workarounds, fee-stack math, and what to do before checkout.

Decision spine

This page should not be a dead-end database row. Use it to move into the fee-avoidance guide, then into the tool that solves the actual problem.

Real traps to watch
  • The "Flight Credit" Trap: If you switch to a cheaper flight, you don’t get cash back—you get a credit that expires in 12 months.
Expert move

The 2-Bag Weight Split: You get 2 free bags. Pack a light foldable duffel so you can split a 51 lb bag into two ~26 lb bags at the kiosk and avoid the $100+ overweight fee.

Published fee rows

23 verified rows
CategoryAmountConditionsPricingWhenSource
Carry on0.00 USDCarryon + personal item included: (a) one carryon bag not exceeding 10 x 16 x 24 inches; and (b) one smaller personal item stowable under a seat or in an overhead compartmentNot publishedper flightSource
Checked baggage0.00 USD1st checked bag: free (applies to travel booked and ticketed before May 28, 2025)per directionNot publishedSource
Checked baggage0.00 USD2nd checked bag: free (applies to travel booked and ticketed before May 28, 2025)per directionNot publishedSource
Checked baggage35.00 USD1st checked bag (for travel booked and ticketed and/or changed on or after May 28, 2025)per directionNot publishedSource
Checked baggage45.00 USD2nd checked bag (for travel booked and ticketed and/or changed on or after May 28, 2025)per directionNot publishedSource
Checked baggage35.00 USD1st checked bag (for travel booked and ticketed and/or changed on or after May 28, 2025)per directionNot publishedSource
Checked baggage45.00 USD2nd checked bag (for travel booked and ticketed and/or changed on or after May 28, 2025)per directionNot publishedSource
Checked baggage35.00 USD1st checked bag (for travel booked and ticketed and/or changed on or after May 28, 2025)per directionNot publishedSource
Checked baggage45.00 USD2nd checked bag (for travel booked and ticketed and/or changed on or after May 28, 2025)per directionNot publishedSource
Checked baggage0.00 USD1st checked bag: free (for travel booked and ticketed and/or changed on or after May 28, 2025)per directionNot publishedSource
Checked baggage0.00 USD2nd checked bag: free (for travel booked and ticketed and/or changed on or after May 28, 2025)per directionNot publishedSource
Checked baggage150.00 USD3rd+ checked bag (for travel booked and ticketed and/or changed on or after May 28, 2025)per directionNot publishedSource
Oversize baggage200.00 USDOversized item: in excess of 62 inches but not more than 80 inches; charge is in addition to the standard checked bag feeper directionNot publishedSource
Overweight baggage100.00 USDOverweight item: 51–70 lbs; charge is in addition to the standard checked bag feeper directionNot publishedSource
Overweight baggage200.00 USDOverweight item: 71–100 lbs; charge is in addition to the standard checked bag feeper directionNot publishedSource
Oversize baggage200.00 USDOversized & overweight: only one $200 charge applies if the piece is both oversized and overweight (as long as it does not exceed 100 lbs); standard checked bag fee also appliesper directionNot publishedSource
Seat selection0.00 USDNo seat selection with Basic fares; a Standard seat will be assigned at check-in (flights departing on or after January 27, 2026). Until then, Southwest uses open seatingNot publishedcheck-in / boardingSource
Seat selectionVaries USDPaid seat upgrades (for flights departing on or after January 27, 2026)Not publishedper segmentSource
Change cancellation0.00 USDNo cancel fees (all fare types eligible for cancellations without a fee); failure to cancel at least 10 minutes prior to scheduled departure may result in forfeited travel fundsNot publishedbefore departureSource
Same day change0.00 USDFree same-day change available only for Choice Extra, Choice Preferred, or Choice fares; Basic fares not eligible unless fare is upgradedNot publishedday of travelSource
Same day standby0.00 USDSame-day standby available; request must be made at least 10 minutes prior to scheduled departure of original flight; if using app/mobile web for standby, must list 30 minutes ahead of scheduled departureNot publishedday of travelSource
Unaccompanied minor100.00 USDUnaccompanied minor (UM) service charge (ages 5–11): U.S. Mainlandper directionNot publishedSource
Unaccompanied minor35.00 USDUnaccompanied minor (UM) service charge (ages 5–11): Between Hawaiian Islandsper directionNot publishedSource

Use this page the right way

The fee table is the evidence layer. The value comes from connecting it to trap logic, enforcement reality, and the next action that lowers your all-in cost.

Compare against nearby alternatives

Core authority airline

This route is part of the Core 10 set. Treat it like an authority page that should feed users into guides and deterministic tools, not like a leaf node.

Sizer Reality Check

Carry-on measurements usually include wheels and handles. A bag marketed as "22 inches" can still fail if the real outer shell runs tall or will not compress when gate staff starts enforcing size visually.

Legacy-Carriers Baseline22 x 14 x 9 in
Traveler MoveMeasure the real shell

Legal Disclaimer

• Information subject to change without notice.
• This site is an independent reference and is not affiliated with any airline.
• Fees are documented only from verifiable, airline-published sources.

Database ID: southwest

If a row is missing or unclear, the right move is to link to the carrier source or mark the uncertainty, not invent confidence.

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