Can I add frequent flyer numbers to yahoo travel flights that are already booked?

I signed up for a frequent flyer program after I booked a flight and want to add it.Can I add frequent flyer numbers to yahoo travel flights that are already booked?
Yes, very simple.. When you check in for your flight, if you use Self Check in, look for a link to ';add frequent flier # ';. If you have an agent check you in then just give them your ## and tell them to put it in for you..Can I add frequent flyer numbers to yahoo travel flights that are already booked?
I don't know but even if it's possible I wouldn't trust them to forward the information.





Be sure to show your FF card when you check-in so it's registered for your flight. Otherwise it's always possible to claim miles after the flight, logon to your account and provide the flight details.
Just give them your frequent flyer number when you check-in. Don't forget to do it again when you check in for your return flight as well.