What is southwest airlines flight change policy? With Southwest Airlines, changing a flight is a fairly simple and hassle-free process. The best part is that there won't be a cost due to Southwest's no-penalty change policy! The only requirement is that you have to inform your original departure time of the modification at least 10 minutes beforehand. If you made your current flight reservation online, use the same steps to make a modification. You must call Southwest to make modifications if you booked your current flight over the phone. https://www.travomojo.com/flight-change-policy/southwest-airlines-flight-change-policy/