Customers who purchase an Anytime fare will automatically be checked in to their flight 36 hours prior to scheduled departure?that's 12 hours before our traditional 24-hour check-in. You will receive an earlier boarding position, improved seat selection, and earlier access to overhead bins.

The fastest way to check-in for a Southwest flight in 2026 is via the Southwest Mobile App exactly 24 hours before your scheduled departure. Southwest does not assign seats; instead, your boarding position (A, B, or C) is determined by the order in which you check in. To get an edge, you should have the app open and your confirmation number pre-filled, hitting the "Check In" button the split-second the clock turns. For those who want to skip this stress entirely, the "EarlyBird Check-In" add-on (starting around $15–$25) will automatically check you in 36 hours in advance, usually securing a high "A" or "B" group position. If you have a premium "Business Select" fare, your check-in is effectively "pre-cleared" with a guaranteed A1–A15 position, providing the absolute fastest path to boarding and overhead bin access.