When I look at changing a flight to a cheaper flight, I see that I'll be issued a "United Airlines Travel Certificate" (for the difference in cost, minus the change fee).
Can that credit then be used to buy a ticket for another passenger, or only me?
So I ended up going to the source, tweeting United Airlines directly.
They've just replied, saying that YES, they are transferable, and provided a link with more information:
The link is basically instructions on use of one of these certificates, and from those instructions it's merely a code, so not bound to any particular passenger.
United doesn't have a "one rule fits all" for certificates, so you need to check the rules for your specific one. They are usually provided in the email about the eCertificate or printed on the back of a paper certificate. United unfortunately does not provide terms on their website for certs.
The certificates in general are restricted to airfare only, can't be applied towards extra fees like baggage or enhanced seats. But in years past (it has been a while since I had a UA cert) you could apply it to someone else's airfare if they were traveling with you on the same flights.
