Opt for a voucher instead of a round-trip ticket

Free roundtrip air tickets usually come with many restrictions and usually only apply to domestic destinations. It’s a far better deal to get a voucher of several hundred dollars that can be used toward any future flight. Of course nothing’s that simple, so if you’re offered a travel voucher, ask the following questions: Is it “positive space”—that is, you’ll be able to get a reservation in advance? Or “space available,” which means you will have to stand by? Is it subject to blackout dates or other restrictions? Can it be use in the United States as well as abroad?