Originally Posted by
chandi
When out son was 6 weeks old I booked 2 economy plus 1 infant ticket ickets and used 2 SWU certificates to upgrade my wife and my self. We were not charged for the infant upgrade as he was traveling as a lap child.
Not sure if you were traveling domestic here (and used SWUs!) but for domestic itins lap children do not have to pay for an infant fare. For international travel they do. As stated above: 10% of the full fare for the paid cabin (miles or $$). Upgrades count as paid in the lower cabin. Of course, call UA to be sure.