Southwest Airlines is a one-of-a-kind airline in the aviation world. Because of Southwest's flight change policy, we've given it the moniker "unique." Southwest Airlines is noted for having the most liberal change policy of any of the major airlines. Most airlines impose a significant penalty for altering a ticket after it has been purchased. Southwest Airlines has set the standard for not collecting change costs on domestic and international flights, setting an example for other airlines. We've put together a guide to Southwest Airlines Date Change Policy so you can be prepared if you need to modify your itinerary.