If one enters "SFO" and "BKK" for flight search at united.com, up comes low cost economy options like SFO-HKG on UA & HKG-BKK on HX, for $526 all in. The HX flights are not code shares. However nowhere does it mention that Hong Kong Airlines is not a Star Alliance member. This is the downside of flying this routing - no lounge access in BKK if flying economy, no mileage earning for this segment, ...
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