Join Date: Apr 2009
Location: Bye Delta
Programs: AA EXP, UA Silver, HH Diamond, IHG Plat, Hyatt Plat, Marriott Titanium, Nat'l EE, Avis PC, Hertz PC
Posts: 16,633
OU is the fare class for complimentary upgrades on a flight where the front cabin is marketed as Business Class (often either an international flight or a continuation of one). As opposed to RU, which is the fare class for complimentary upgrades on a flight where the front cabin is marketed as First Class.