Cathay Pacific looks like it is in a fare war with Hong Kong Airlines. Both of these airlines have tickets from San Francisco to Hong Kong around $388 round trip with nonstop flights. United Airlines has nonstop flights from $418rt from August 2018.
Cathay Pacific drops their ticket price to $347.11 round trip on some dates late August to early December 2018.
Expedia knocks a dollar off that ticket price.
Departure Dates: late August to early December 2018.
Cathay Pacific Airways Expedia.com tick
San Francisco – Hong Kong HKG – San Francisco
$346.11 round trip Mon Sep 17 – Mon Sep 24 (6 nights in Hong Kong).