Hi all -- I have a dumb question: Do airlines usually allow mileage upgrades using miles from someone else's account? So for instance I buy a economy class ticket on airline X, can my wife use her miles to upgrade me?

Thanks,
Sankaps..

It depends on the airline. United does. Why don't you go to the airline's own FF weboage and check it out yourself?

United and American have this ability.
Not sure about others.

Pretty much all of them let one person get any award for someone else. Every one I've ever looked at does. However, that's not the same thing as saying the specific airline you care about does: there may be an exception out there. You didn't say which airline you're asking about, but they all have forums here. If you check the forum for that airline, you may find the question has already been answered - often in a "sticky" FAQ thread at the top. If not, you'll at least find a bunch of people who know the answers for that airline and won't ramble on about "pretty much all of them," since you don't care about pretty much all of them.

(The advice in post #2 to check the airline's Web site is also good, but we all know that airline Web sites aren't always easy to navigate and don't always have the information we're looking for in a place where we can find it.)

Thanks all. The airline I am asking about is Delta -- could not find this on their website. But then I got more generally curious and wondered if in general airlines do this. I had always assumed that most airlines allow you to redeem miles for free ticket redemptions for anybody, but not for upgrade awards. Guess I was under the wrong impression all along!

On most carriers that is possible. The person upgrading you would need to log in with his/ her data and go to Sponsor an upgrade. Then she/he will be asked for a booking reference ( Record Locator, Confirmation code..). This is How UA does it.