Unlike other low cost airlines, airport check-in is free.
Of course, you can also use online check-in, which always starts 24 hours before departure. Print your boarding pass either at home or at the automated kiosk at the airport.
If you don't want to take the time to print, have your boarding pass sent to your mobile phone and just scan the barcode at the airport. Before that, however, you need to download a mobile app to scan the QR code at the airport.
We recommend checking in online as soon as possible, ideally exactly 24 hours before departure. Southwest Airlines has a "free-seating" policy, meaning they don't assign you a specific seat on the plane, but the selection process works on a first-come, first-served basis. However, you will be assigned a specific group (borading group) at check-in. The groups are then used to board the aircraft. It is a direct proportion of the time that the earlier you check in online, the earlier you board the plane.
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