Originally Posted by
xcfly
that’s very useful but how can one determine “the price would’ve paid had you purchased one way ticket that day”? Cathay keeps a historical rate for all flights?
Yes, they keep enough data to tell the pricing of your ticket.
For HKG-JFK ticket, a single way ticket will usually cost 70-9x% of the return ticket; if you want to cancel the partially used ticket, you might only receive the tax back because they also impose a cancellation charge.