Traveller reference · WN
Southwest Airlines
No alliance · IATA WN · a point-to-point network rather than a hub system
Travelaidnow is an independent travel agency and is not Southwest Airlines, nor affiliated with or endorsed by it.
This page is a general reference written by our team. Baggage allowances, fees and policies are set by the airline and change without notice, so confirm anything that affects your trip with Southwest Airlines directly before you travel.
Official site: southwest.comSouthwest operates differently from the other large US carriers in ways that affect planning. It flies point-to-point rather than routing everything through hubs, it does not sell tickets through most third-party comparison sites, and for decades it did not assign seats at all.
Several of those long-standing distinctions have been revised recently, including its approach to seating and its baggage policy. If your understanding of Southwest is based on flying it a few years ago, it is worth checking the current terms directly rather than relying on what used to be true — the airline's most famous policies are precisely the ones that have changed.
Southwest Airlines at a glance
- IATA code
- WN
- ICAO code
- SWA
- Based in
- United States
- Alliance
- No global alliance
- Type
- Low-cost
- Frequent flyer
- Rapid Rewards
How Southwest Airlines baggage works
Southwest's baggage policy was, for many years, its best-known feature and a genuine outlier among US airlines. That policy has since been revised, and describing the old terms as though they still applied would be actively misleading.
Because this is an area of active change, we are not stating an allowance here. Check southwest.com for the terms attached to your fare tier before you travel, particularly if you have not flown the airline recently.
Check-in
Check-in has historically opened 24 hours before departure, and under the airline's traditional open-seating model the exact minute you checked in determined your position in the boarding order.
Southwest has been moving away from open seating toward assigned seats, which changes what check-in timing actually buys you. Confirm how your specific flight is operating when you book.
Boarding
Southwest's traditional system assigned each passenger a group letter and a position number, and travellers chose any open seat once aboard rather than sitting in an assigned one.
With the shift toward assigned seating, boarding order and seat selection work differently from the model most people associate with the airline. Treat older advice about checking in exactly 24 hours ahead with caution and read the current process for your flight.
Before you fly Southwest Airlines
Southwest fares are largely absent from comparison sites
The airline distributes mainly through its own channels, so a metasearch result that looks complete for a domestic route may simply not include it. On markets Southwest serves heavily, checking directly is worth the extra step.
Its airports are often the secondary ones
Dallas Love Field, Chicago Midway and Houston Hobby rather than DFW, O'Hare and Bush. That can be an advantage or a problem depending on where you are going, and it matters if you are connecting from an international arrival at the primary airport.
There is no interline agreement to fall back on
Because Southwest does not participate in an alliance or standard interline arrangements, a disruption cannot be solved by rebooking you on another carrier the way it often can elsewhere. On a tight schedule, that is a real consideration.
How often Southwest Airlines runs late
Southwest Airlines files its operational performance with the US Department of Transportation every month. These are those filings, not our estimates. The airline accountability index puts these figures next to every other reporting carrier, and publishes the underlying table as a file if you want to check the arithmetic.
Southwest Airlines — domestic US operation
- Arrived over 15 min late
- 27.5%of 120,646 flights
- Cancelled
- 0.4%
- Average delay
- 15.6min
Of every filed minute of delay on Southwest Airlines domestic flights, 81.1% was coded as carrier delay or late-arriving aircraft and 2.3% as extreme weather. The commitments US airlines make to rebook you and cover meals turn on whether a delay was within their control, which is why the split is worth reading — though which side your own flight fell on is not something a monthly total can answer.
- Carrier delay — 29.8%
Filed against the carrier's own operation — crew, maintenance, fuelling, baggage. - Late-arriving aircraft — 51.3%
Filed because the inbound aircraft was late. What delayed it is not recorded. - Air traffic system — 16.3%
Volume, routing and airport capacity, attributed to the national airspace system. - Weather — 2.3%
Extreme weather recorded as the cause.
That first figure is two filed categories added together: carrier delay, and late-arriving aircraft. BTS reports them separately and the sum is ours. It is not a finding of fault — the late-arriving code records that the inbound aircraft was late, not what delayed it, so some of it began as weather or traffic flow earlier in the day. Both components are listed above so you can reject the sum.
These are monthly aggregate filing codes. They cannot establish what caused your individual flight, whether it was within the carrier's control, or whether compensation is owed.
Its least reliable routes this month
Routes with at least 300 flights in the month. Thinner routes are excluded because a handful of bad days on a weekly service produces a dramatic percentage that means nothing.
Figures cover May 2026, a single reporting month, from the US DOT Bureau of Transportation Statistics On-Time Performance database. Retrieved 2026-07-28. Reporting under 14 CFR part 234 covers domestic US scheduled service only, so no international route appears — including anything to or from Mexico.
If your Southwest Airlines flight is delayed or cancelled
As a US carrier, Southwest Airlines is covered by 14 CFR part 260, which is a refund rule rather than a compensation one: past a significant delay you may have your money back, but US law owes you nothing for the disruption itself. The threshold is 3 hours on a domestic itinerary and 6 on an international one, and the right survives only while you decline a voucher or rebooking.
Check what Southwest Airlines owes youOther low-cost carriers we cover
Carriers that price and package a ticket along similar lines, which is usually what matters when you are weighing one against another.
Planning a trip rather than researching a carrier?
Our route and airport guides cover the journey itself — when demand peaks, which airports work, and how long the connection really takes.
FAQ
Southwest Airlines — common questions
General guidance only. Southwest Airlines sets these policies and can change them, so confirm anything that affects your trip at southwest.com.
Does Southwest still offer free checked bags?
The policy that made Southwest distinctive has been revised, and repeating the old terms as current would be misleading. This is exactly the kind of detail that changes without much warning, so check the baggage terms for your fare on southwest.com before you travel rather than relying on the airline's long-standing reputation.
Does Southwest assign seats?
For most of its history it did not — passengers received a boarding position and chose any free seat on board. The airline has been transitioning toward assigned seating, so the answer depends on when and what you are flying. Confirm the arrangement for your specific flight at the time you book.
Why can't I find Southwest flights on comparison sites?
Southwest has historically limited distribution of its fares through third-party channels, so many metasearch tools show an incomplete picture on routes it serves. If you are pricing a domestic US route where Southwest flies, checking it separately is worth doing before concluding you have seen the market.