Changing airline tickets

[Galaxy]

I'm flying out-of-state for a surgery next week. I know the tentative date I should be able to come home. However, it is not set in stone (as you kind of have to just wait to until the surgery). Can you change your airline ticket (and your guest that is flying with you) if you have a doctor's note providing proof, without being charge?

[samifan24]

Are you flying Southwest? My sister was flying Southwest home from college last year and had to switch the day she was flying in one day at the very last minute. Southwest allowed her to do this without any penalties and I have heard similar stories about Southwest in the past.

[Lathum]

It depends on the airline and if the flight you are changing to would have been more expensive.

[Desnudo]

Buy a refundable ticket