Originally Posted by UnitedSkies
To further clarify, if you see a $500 r/t UA fare for say, SFO-SIN

filed in the GDS, and given that fuel surcharges from the US to SIN are $180 roundtrip these days, the total is $680. UA will advertise this fare as $340 each way based on required roundtrip purchase.
I have to disagree with you here. United will most likely adverise this as a $250 one way fare (based on round trip). See
ryan182's example.
IME, United almost always advertises the base fare (exclusive of fuel charges and taxes) then puts in the *. I'm OK with this, although I find it annoying as it's the American way to not quote the total cost at the register in advertising.