There IS a difference between the two.

XY/XC/XF booking codes exist when booked in a PNR (and should also show up on an itinerary printout), with the segment looking something like this:

UA7708XY 17OCT INDIAD HK1 130P 451P SU

The difference between XY and Y is that XY inventory is much more controlled, as it is the Saver award. The same rule goes for XC/XF. Saver award bookings are always preceded by an X.

Your award is booked in Y when you have paid the Standard amount of miles for your award, the same when booked in C or F. Standard awards are booked as if full fare tickets in the booking code.

Condition One: Your boarding pass in the lower left hand corner will still read "BOOKING CODE Y", even though only miles exchanged hands. It reflects the booking code in your reservation, nothing more. There are SSR's added to the reservation that inhibit mileage earning, and the electronic ticketing and PNR information knows all and sees all.

Happy Travels!
Kai

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SkyWest Airlines - your friendly regional carrier and largest United Express carrier!

Any opinions expressed by myself are mine alone and may not necessarily reflect the opinions of my employer, SkyWest Airlines, or those of our majors partners, United Airlines, Delta Air Lines, and Continental Airlines, respectively.