Originally Posted by
JJeffrey
If you decide not to take the return portion, then just pull up your itinerary at aa.com and cancel it. Then, at a later date if you want to try to use the remaining value on the ticket for another US>Europe segment, you can call AA and see what the changes would cost. Otherwise, the ticket will just go away after a year.
If the fare rules require a roundtrip, it’s unlikely there will be any residual value from the cancelled return.